Invasion Biology

POMPOM WEED: CAMPULOCLINIUM MACROCEPHALUM (ASTERACEAE)

2007-03-02T12:05:00.000+02:00

Pompom weed (Campuloclinium macrocephalum) threatens the survival of grasslands and wetlands throughout South Africa. It was first recorded (1970 and1980) in wild areas (Durban and Pretoria) and it becomes a prominent weed in Gauteng. This plant species is native to South and Central America and Mexico. It is the worse invader than chromolaena odorata because it has a potentially far wider distribution and altitude range (0-1900 m), it resistant to front and fire, it reproduces from both seed and vegetative from a rootstock, it has a tuber-like food storage organs which are capable of regeneration and it is very ornamental and spread mostly by ignorant people.
[1]

How does the Pompom weed spread? This plant species is one of kind which produces amounts fluffy seeds that are wind dispersal. Humans can contribute a lot in spreading the seeds by vehicles carrying the seeds in the mud on their tyres and one picking the flower and later discarding the seeds. Most of the alien weeds and invader plants in South Africa occur during spring and summer seasons, it transforms the landscape from green to pink. The pompom weed (Campuloclinium macrocephalum) is more unique and it increase in spreading than other weed. This member of Asteraceae family it reduces both the biological diversity and carrying capacity of vleis and veld.
[2]

Control of pompom weed, the only herbicide registered for use on pompom is Brush-off by DuPont and the two physical methods including uprooting and burning of the plant. The preventing of seed production can limit the spread of plant and “through constantly cutting back the aerial growth the nutrients stored in the rhizomes will be depleted” therefore this will limit the seed production. The active ingredients 2,4-D/picloram chemical is used by farmers in spraying the pompom weed and the control results shows good in use of this chemical.
[3]

The farmers, conservation officers, ecologists and WESSA members have suggested that the pompom weed “has already begun to fulfil its potential” and if one sees it, he/she must record the date and location where it occurs in order for Alien invader plant project to verify and record the sighting. What does the legislation says? “According to the new proposed regulations 15 and 16 of the Act on conservation of Agricultural Resources, 1983 (act 43 of 1983), the pompom weed is to be declared as a weed”. Therefore the act imply that “the plant must be eradicated wherever it is found in South Africa” and if one decide to cultivate or trade the plant, the punishment will be taken by law. [4]

References:

Fernando M.K and Marina .O. Ballon vine, Pompom weed, Barbados gooseberry. Agricultural Research Council, Plant protection Research Institute, Pretoria, South Africa. [Iternet] [Cited 2007 Feb 26]. Available from:
http://www.usda-sabcl.org/projects/Emergentweeds.htm
Wildy E. Alien Invader Plants Projects. [Internet] [Cited 2007 Feb 26]. Available from: http://www.geocities.com/wessaaliens/species/pompom.htm
Henderson L. Southern African Plant Invaders Atlas. Volume 1 page 2-4. [Internet] [Cited 2007 Feb 27]. Available from: http://www.tshwane.gov.za/pompomweed.cfm
Malherbe C. Pompom weed. Gauteng Department of Agriculture, Conservation, Environment and Land Affairs http://www.africainaday.org.za/Seringveld/pominfo.htm

Ramapulana Nkoana
CSIR Pretoria
0001
Tell: +27 12 841 2133
Fax: +27 12 841 4405
Email: pnkoana@csir.co.za
: puli.nkoana@gmail.com
My blogger URL: http://pnkoana.blogspot.com

GREAT THREAT POSED BY EUROPEAN STARLING IN NATIVE SPECIES

2007-01-24T18:43:00.000+02:00

European starling Sturnus vulgaris is a native species in Eurasia and North America. It has been introduced intentionally to countries like Australia, New Zealand and South Africa for aesthetic reasons and also for the control of insects, but it is now ironically considered as a pest itself. It has been recently introduced in South America where it is posing a serious threat to the continent because it is spreading very fast [1].

The descriptions of S. vulgaris include; medium sized, black songbird with short, triangular wings with spotted feathers and short tail. Breeding adults and no-breeding adults are differentiated by feathers. The feathers of a breeding adult are thin pointed with yellow bill and black in colour whereas the non-breeding has a black beak and light spots [1].

This alien species has the ability of growing very fast because it is a habitat generalist, it has the ability to utilize a wide variety of habitat types, nest sites and food sources. The fact that it co-exist with humans allows it to become established in agricultural fields, cities, sewage treatment and garbage dumps. [1]

They have a negative impact as they carry diseases like blastomycosis, beef measles and histoplasmosis which are of higher risk to human beings. [1].
Farmers are also experiencing huge problem caused by S. vulgaris as it damage crops, berries and grapes. They also transmit diseases to domestic animals by contaminating water and food sources through live storks.

The overabundance of starlings causes a lack of avian diversity, S. vulgaris drive-off native species like bluebirds (Siglia spp), Purple martin (Progne subis) and Tree swallows (Ridoprone bicolor). After a century of their introduction they contribute in the decline of the above listed species. They have observed taking over the nests of House Sparrows (Passer domesticus) [2].

They pose enough threat to songbird in a way that it is now allowed to kill starling in U.S and Canada and sometimes a bounty is given off to killers. They are not protected by American wild life Conservation laws which make the killing issue not surprising. In other cities their nests are destroyed by human intervention where they intentionally set up the nest boxes in backyards and wooded areas, some also allow Peragrine falcon to build up their nests so that they can help with the control of European starling, as Peragrine falcon are strong eaters of starlings [3].

Economic concern was found in airport at runaways as European starling causes aircraft disasters by clogging up engines causing a shut down of the plane.
One of the Economic benefits posed by European starling in agriculture is the regulation of the number of pests eating the crops. They also serve as food source for some cultures along the Mediterranean Sea [1].

The invasion of European starling is not environmental friendly, it is true that they do assist farmer by controlling pests but the problem still lies immediately as they finish the pests because they become pests themselves and start eating the crops. They also pose high health risk diseases to both humans and animals which concludes European starling as a higher risk invasive species that needs to be removed fast.

References

1. Matthews, S. and Brandt, K. 2006. South American Invaded: the growing danger of invasive alien species. [Internet]. 23 January 2007; 08:57 UTC [Cited 23 Jan 2007]. Available From:
http://www.gisp.org/casestudies/showcasestudy.asp?id=274&MyMenuItem=casestudies&worldmap=&country=
2. Peterson, R. T. 1947. A field guide to the birds. [Internet]. 23 January 2007; 10:17 UTC [Cited 23 Jan 2007]. Available From:
http://edis.ifas.ufl.edu/UW118
3. Wikipedia contributors. Peregrine Falcon [Internet]. Wikipedia, The Free Encyclopedia; 2007 Jan 22, 07:02 UTC [cited 2007 Jan 24]. Available from: http://en.wikipedia.org/w/index.php?title=Peregrine_Falcon&oldid=102387030.

Dianah Nangammbi
Cilla CSIR
P.O Box 395
Pretoria
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Tel: +27 12 841 2133
Cell: +27 73 121 3589
Email: dnangammbi@csir.co.za
URL: http://wwwdianah.blogspot.com/

The Invasion of South Africa Biome by Feral Species (Opuntia Stricta - Prickle Pears)

2007-01-24T18:17:00.000+02:00

The Opuntia Stricta has invaded South Africa biomes. It was regarded as the feral species, this because it invade the rocky slopes and river banks from domesticated environment. Opuntia Stricta is an indigenous species of North America1. It has been introduced in South Africa and other continent as ornamental plant, garden plant and it was used as a fence. The species grow as shrub.1

The Opuntia Stricta has a fleshy stem with no leaves 3.The fleshy stem grows like leaves and it has spines with hairy features. The spines make it unpalatable to other animal species. The Opuntia Stricta bears fruits that are palatable to humans. It was studied that it can cure sugar diabetes and stomach-ache. It also helps to reduce alcohol hangover. 3

Opuntia Stricta favourable habitant is in the rocky slopes and in river banks. However, it also invades disturbed area such as cultivated area and wetlands. The Opuntia Stricta has invaded the rocky slopes and riverbanks out compete the indigenous species.1

In south Africa Opuntia Stricta has been declared weeds this because when it invade the area it grows in dense that end up restricting the growth of other plant species. In Kruger National park (South Africa), the Opuntia Stricta has invaded large area. When opuntia stricta invade the area, it replaces other species.1

The opuntia stricta spread through garden wastes, some with water current.1 The Opuntia Stricta have the ability to grow from any parts of its fleshy stem. Birds and animal can spread other species of opuntia stricta like common pear 2. The management of this opuntia stricta considered difficulty when is done physically. This because it can grow again if it is not disposed well 2. Spraying with woody weeds and biological control are effective if they are applied well. This is because in warm climates it needs to be reapplied again in winter.2

In general, the feral species can have more impact in our ecosystem. This need to be addressed and managed before the species invades our biome from domesticated species.

Reference:
1. Global invasive species Database, 2006. [Internet] Cited 2006 Jan 24 Available from: http://www.issg.org/database/species/ecology.asp?si=104&fr=1&sts=

2. Opuntia stricta [Internet] Cited 2006 Jan 24 Available from: http://www.esc.nsw.gov.au/Weeds/Sheets/shrubs/S%20Prickly%20pear.htm

3. Wikipedia contributors. Opuntia [Internet]. Wikipedia, The Free Encyclopedia; 2007 Jan 22, 19:39 UTC [cited 2007 Jan 24]. Available from: http://en.wikipedia.org/w/index.php?title=Opuntia&oldid=102492834.

Mr Elelwani Muanalo
CSIR Pretoria
NISL- Ecological Informatics
P.O. Box 395
Pretoria, 0001
Tel: +27 12 841 2133
email: emuanalo@csir.co.za
Blogger url:http://muanalo.blogspot.com/

"The best way to predict the future is to invent it" Alan

THE LEUCAENA LEUCOCEPHALA SPECIES AND ITS NEGATIVE IMPACT ON THE ENVIRONMENT

2007-01-24T17:21:00.000+02:00

The Leucaena leucocephala is a scientific name. It has many different common names; wild tamarind, lead tree, jumby bean or lamtoro. This plants is belongs to the family of Fabaceae. It is also belongs to the order of fables and the class Magnoliopsida. Leucaena leucocephala is a native species of Central America and Mexico. The species is listed as widespread in South America.

The Leucaena leucocephala is listed as a weed in Brazil, Agentina and in Bolivia. In this place, the species is taken as serious invader in the Islands of Fernando de Noronha. The species spread all over the tropical and sub-tropical parts of the world. Leucaena leucocephala is one of the plants that are promoted by international agroforestry organisation. It was promoted for food purpose, because it produces nutritional food for livestock. The foliage and seeds of Leucaena leucocephala contains the amino acid called mimosine (Matthews and Brandt 2006). The mimosine acid is very poisons to other plants which lead to invade the riverbanks, roadsides, cultivated land, and forest margin and in waste land.

During 16 century Leucaena leucocephala again introduced into Philippines for the purpose of feeding the ruminant livestock. Now it is spread all over the pacific region of Asia where it is previously used as agroforestry. This plant is easily propagated from seeds but it may grow from cutting. Its seeds are dispersed by vertebrates’ animals such as birds and rodents. Now this species is not planted at all in Asia. Leucaena leucocephala is a slow growing tree especially when it grows in high altitude.

Leucaena leucocephala is a small thornless tree or shrub that can reach a height of 10m tall. In its home environment Leucaena leucocephala prefers to grow on coastal sands and on shallow limestone soils. This plant prefers many different types of soils because their roots systems allow it to tolerate many soils types. The Leucaena leucocephala can grow fast with a fertile clay soils (James A.D, 1983). It can grow in alkaline and saline soils and in area where there is low phosphorus and iron in soils. It can not grow in place where flood takes more than three weeks. Leucaena leucocephala prefers to grow with an optimal temperature of approximately 25 to 30 degrees Celsius.

The mature plants of Leucaena leucocephala are well adapted to fire and it can regrow from the burnt stumps. It is easily generate from basal shoots after fire (Lam, 2006). Leucaena leucocephala is a drought tolerant but it is poor adapted to infertile acidic soils. It also prefers to live in disturb areas like, along the road.

In its home environment the Leucaena leucocephala typically occurs as dense thicket forming. It is difficult to mitigate (eradicate) the L. leucocephala as it grow as a dense thicket forming. The glucoside mimosine produced by the seeds and leaves of L. leucocephala cause a problem with the hair of young cattle and horses in places where it introduced. Subspecies leucocephala is particularly precocious and free seeding.

It is concluded that L. leucocephala is accidentally introduced in South Africa by international agro forestry organisation. This organisation introduced this species because it produces the nutrition food for livestock. Unfortunately they are not aware that, this species produce mimosine acid which is very poisons to other species. The acid produced by the seeds and leaves of L. leucocephala destroy the forest margin and cultivated area in South Africa. This species threaten the biodiversity of South Africa because it has the possibility to spread over a long distance. The glucoside mimosine produced by the seeds and leaves of L. leucocephala destroy the hair of young cattle and horses.

The following methods can be used to eliminate the spreads of L. leucocephala species; Biological, Chemical and mechanical methods. A mechanical method involves the removal of invasive species using machines or hands. This method is most useful to eliminate the invasive species. Cutting or burning of L. leucocephala can be applied. This method is mostly useful at the beginning of the year.

Chemical method may also used. This method is used to prevent the spreading of L. leucocephala. This method involves the use of herbicides and pesticides. Herbicides can be used to destroy the L. leucocephala. It allows the person to cut down the stem of L. leucocephala and apply hebicides. Biological control method can be used. This methods is mostly useful to stop the spread of L. leucocephala by releasing new species. All this methods can be used to eliminate the spreads of L. leucocephala. Chemical and mechanical methods are the best methods to eliminate alien species as compared to biological methods.

References

James A.D.1983. Handbook of Energy Crops.[Online].[Cited, 23 January 2007].Available from:http://www.hort.purdue.edu/newcrop/duke_energy/Leucaena_leucocephala.html

Lam, D.W, 2006 Leucaena leucocephala [Online].[Cited, 23 january 2007].Available from: http://www.hear.org/pier/species/leucaena_leucocephala.htm

Linette Netshiheni
CSIR
Pretoria
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tnetshiheni@csir.co.za
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Gorse (Ulex europaeus) in Australia

2007-01-24T17:17:00.001+02:00

Gorse (Ulex europaeus) is considered as one of the worst weeds in Australia. It is regarded as one of the 100 destructive invasive species⁽¹⁾ . Gorse has both economic and environmental impact. The weed is mostly invaded Tasmania and Part of Victoria ^{(2 ).}

Gorse is an indigenous species to Europe from Scotland south to Portugal, Galiza and East of Belgium. (1). Gorse is introduced to “Panama, Argentina, South Africa,China, Indonesia, United States, Hawaii, Canada, Indonesia, New Zealand, Mauritius, Ecuador, Tanzania, Uruguary, Sri Lanka, Turkey and Australia” ^{(2 ).} Gorse were introduced to agriculture as a hedge and for ornamental purposes ⁽²⁾

Gorse is a perennial evergreen shrub. The young braches of the gorse are typically spine. Gorse grows in area that receives 650-900mm⁽³⁾ during the year. However, the gorse also adapted to grow in Tasmania West Coast where the mean rainfall is 2400mm ⁽³⁾. It is also known to grow well on fertile soil, heavy clays, disturbed and light soil. The gorse can survive on poor soil nutrient because they are able to fix Nitrogen. The gorse is restricted to higher rainfall areas and is mainly found in the Fleurieu Peninsula ⁽³⁾.

The species displaces indigenous plants. The gorse has both the negative and positive impacts. Gorse changes a soil condition by both acidifying soil and fixing nitrogen. The gorse removes and preserves nutrients for example Sodium, Calcium and Magnesium and it weakens the soil. The bare soil is mostly found between individual gorse and results to soil erosion especially at the steep slopes. Goose decreases the quantity of forage when they are introduced on rangeland. Gorse is also blamed to disturb the growth of conifer trees. The foliage and seeds of the gorse are highly flammable. The fire which is produced by gorse is hotter comparing to the fire produced by other weeds ⁽²⁾.The gorse also has positive impacts. It is usually used as a hedge plant, windbreaks, ornamental shrubs, gully reclamation, medically purposes and food for livestock ⁽³⁾.

The thickets of gorse can be burnt to the same level with the ground. The seedling will then spray in the next year to decrease seedlings ⁽³⁾. The spray will follow to kill the regrowth of the species. The gorse can be controlled by using mechanical clearing which can control large infestation. The tractor or bulldozers with rippers can be used ⁽³⁾.

References

1. Wikepedia Contributors. Common Gorse [Online] Wikepedia,The free Encyclopedia; 2007 Jan 21; 15:30 UTC [ cited 2007 January 24]. Available from: http://en.wikipedia.org/wiki/Common_Gorse

2. Hill R. 2005. europaeus (shrub,tree). [Online]. [cited 2007 Jan 24] Available from:

http://www.issg.org/database/species/ecology.asp?fr=1&si=69&sts=

3. CRC. 2003. Gorse (Ulex europaeus) [Online]. [cited 2007 Jan 24] Available from:

http://www.deh.gov.au/biodiversity/invasive/publications/pubs/u-europaeus.pdf

Masiya Kedibone

CSIR Pretoria

0001

Tel No: 012 8412123

Fax : 012 842 3676

E-mail :kmasiya@csir.co.zaweblog: http://kedimasiya.blogspot.com/

YELLOW CRAZY ANTS ON CHRISTMAS ISLAND

2007-01-24T17:17:00.000+02:00

Yellow crazy ant (Anoplolepsis gracilipes) is one of the largest and most destructive invasive ants (1). The native range of the species is not known exactly (2), “it may have been originated from Asia or Africa” (1). Yellow crazy ant invaded places such as Africa (South Africa), Asia (Malaysia) South America (Brazil) and Pacific Ocean (Hawaii). Anoplolepsis gracilipes was accidentally introduced to Christmas Island 1915 (3 ) and 1934 (3 ) and widespread to the entire island (3 ) .

Yellow crazy ant has unusually long leg and antennae. The researchers detected one super colony of Anoplolepsis gracilipes in 1989 on a high terrace above the Grotto (3 ) . The super colonies were again detected by researchers from Melbourne’ Monash University in 1997. The researchers were investigating the role of red land crab (Geocarcoidea natalis) on the Christmas Island ecosystem (4).

The Yellow crazy ant killed and displaced approximately ten(3) to twenty (3) millions of crabs on the rainforest floor. Crabs are keystone species of the rainforest. Anoplolepsis gracilipes consumed indigenous crabs and also occupied their burrows. They use formic acid to defend and to suppress their prey such as coconut crabs and reptiles (3 ).

The absences of crabs lead to the growth of seedling and spread of weeds on the Christmas Island. The population of Dendrocnide peltata began to increase and closed tracks which were used by people during their visitation on the Island (3) . At about ninety percent of the trees and shrubs were swarmed with sooty mould which resulted to the extensive canopy dieback. The population of indigenous birds, reptiles and mammals were also reduced. Studies indicated that the predation of immature Fregata andrewsi by crazy ant will result to decline of its population by eighty percent in the next thirty years (5). Anoplolepsis gracilipes is a dangerous agricultural pest (2).

The Park staff and experts struggled to find an appropriate method of baiting ants in 1999 and 2000. The amount of $1.5 from Natural Heritage trust was used to control crazy ants in 2000-2001(5). The successful eradication campaign took place in September 2002 and aerial baiting was used followed by continuous monitoring (5).

Masiya Kedibone
CSIR Pretoria
0001
Tel No: 012 8412123
Fax : 012 842 3676
E-mail :kmasiya@csir.co.za
weblog: http://kedimasiya.blogspot.com/

CITY OF JACARANDA TREES

2007-01-24T16:39:00.000+02:00

Jacaranda trees were introduced to South Africa in 1880 for ornamental purposes. After 100 years until now the trees have invaded most parts of South Africa especially Pretoria (Tswane). The tree that is most often seen is the Blue Jacaranda (Jacaranda mimosifolia) Pretoria in now called the Jacaranda City and most people thinks that Jacaranda trees are native at Pretoria while they were imported from Argentina. The tree is native to the tropical and subtropical regions of Central and South America, the Caribbean and Mexico. There are more than 50 000 trees in South Africa now [1]. The trees are found in enormous numbers since they are planted as street trees, in parks and gardens. During flowering time the city appears to be purple/blue in colour because of the jacaranda flowers. There is also a myth that says “if a flower from a Jacaranda tree drops on your head, you will pass all your exams” [2].

Jacaranda has 49 species of flowering plants which belongs to the family Bignoniaceae. The Blue Jacaranda is a tree which is 5 to 15 metres tall. The bark is greyish-brown in colour and rough. The bark is only smooth when the tree is still young. The twigs are thin and turn to be ziz-zag in shape and they are reddish-brown in colour. The flowers of the Blue Jacaranda are 5 centimetres long, grouped in 30 centimetre panicles. It flowers in spring and early summer and the flowers last for two months. The seeds are found in the woody pods and they are 5 centimetres in diameter. The woody pods contain numerous winged seeds inside. The leaves are 45 centimetres long and compound. The leaflets are up to 1 centimetre long [3].

The Blue Jacaranda likes to grow in a place where there is no risk of frost and they can tolerate the temperature of -7ºC. The Blue jacaranda is regarded as a naturalised species in Miami-Dade country, Florida and Hawaii while in South Africa, Queensland and Australia is referred as invasive. The Blue Jacaranda prevent grow of native species by consuming a lot of water [3].

A company in South Africa has won a World Bank award for manufacturing eco-friendly coffins using wood from invasive non-native plants [1]. This is one of the reasons why the jacaranda tree was planted in South Africa. So some people may want to plant more plants so that they can make profit from the tree or maybe this can reduce the number of trees.

The government listed the jacaranda as an invasive species, which means the trees which already exist must be kept but no more planting of the jacaranda tree. So people did not agree with the government, they wanted to replace the dead trees [1]. The jacaranda trees are beautiful especially during flowering time (spring).

Reference

1. http://news.nationalgeographic.com/news/2005/09/0916_050916_triffidweed_2.html

2. Wikipedia contributors. Jacaranda [Internet]. Wikipedia, The Free Encyclopedia; 2007 Jan 12, 07:06 UTC [cited 2007 Jan 23]. Available from: http://en.wikipedia.org/w/index.php?title=Jacaranda&oldid=100177697.

3. Wikipedia contributors. Blue Jacaranda [Internet]. Wikipedia, The Free Encyclopedia; 2007 Jan 1, 23:10 UTC [cited 2007 Jan 23]. Available from: http://en.wikipedia.org/w/index.php?title=Blue_Jacaranda&oldid=97815550.

Lethabo Mosomane
CSIR
Pretoria
0001
Tel: 27 12 841 2133
Fax: 27 12 842 3676
mail: lmosomane@csir.co.za
http://lmosomane.blogspot.com

FIRE ANTS GIVE A BURNING BITE

2007-01-24T16:31:00.000+02:00

It was on the 4^th December 2006 when I read about the fire ants (Wasmannia auropunctata). I read the article from the "Daily Sun" newspaper and the article was talking about the dangerous of the fire ants. According to the daily sun, there are over 280 species of fire ants species on the world (1). The fire ants are reddish brown to black in colour. The length of fire ants ranges from 1millimetres and above. Fire ants are native at southern and central part of America and they are invaded in west of Africa (Gabon, Cameroon). According to the article, South African not yet invaded by Wasmannia auropunctata (2).

Fire ants prefer to dwell in disturbed areas (garden) and in riparian zones. They are also prefers to live in large colonies. Fire ants also produce mound in the open areas. Fire ants (Wasmannia auropunctata) are very dangerous insects for human and other species. Fire ants attack small animals and kill them by injecting venom (poison). Wasmannia auropunctata feeds on seeds, plants, and crickets.

Fire ants can bite and inject venomous sting into eyes of other species and it will cause blindness. The article also informs the people stay away from fire ants and not tough the nest of the ants because they can spray a powerful acid when it stings that will cause wound. Fire ants can cause declines in other organisms. They also compete with indigenous ants within the affected area.

References:

1. Sun Reporter. 2006 December 4. Daily sun. page 38 ( col 2)

2. Wetterer J. k. Wasmannia auropunctata. Global Invasive Species Database. [Online]. 2006 June 20.[Cited 2006 January 24]. Accessed on:http://www.issg.org/database/species/ecology.asp?si=58&fr=1&sts

Lizzy Maluleke

CSIR PTA

0001

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WATER HYACINTH AND ITS INVASIVENESS OUT OF THE CONTINENT OF THEIR ORIGIN

2007-01-24T16:28:00.000+02:00

Water hyacinth is the plant which floats freely in the water. The plant is indigenous in
the continent of South America. Globalisation, International trade and transportation lead to the spread of water hyacinth in the continents of Africa, North America, Asia and Australia. In South Africa, Water hyacinth first came into existence in the province of KwaZulu-Natal in 1910 (Coetze, 2007) from South America. The species can rise to the height of approximately 1m in height above the water.

The species is now spreading in the Eastern part of South Africa. The plants serve as habitats for small invertebrates animals such as Fish and Frogs. The modes of dispersal include movement of People and Ships all across the boundaries. People move from one place to another either as part of tourism, trade, and other sport activities such as soccer, rugby and tennis. When People move from one place to another they use different types of transport such as trains, buses and planes. The types of the transport that they use carry the alien invasive species from one place to another. The species has been found to be a problem in Kenya where it suppresses other aquatic plants (Coetze, 2007). The plants float on the water and prevent sunlight from reaching other aquatic plants.

The prevention of the sunlight from reaching other aquatic organisms mean that other organisms will die because of the absence of the oxygen and the process of photosynthesis is reduced greatly. Lack of sunlight mean that the process of photosynthesis in water is no longer going to take place. If the process of photosynthesis is no longer going to take place, this means that plants which live in water such as algae (autotrophic) will no longer manufacture their own food. Small animals will die because there will be no longer food which is available for them. In countries such as Australia and Papua New Guinea, the plant destroys native plants. The killing of the native plants by water hyacinth is encouraged by the fact that, there are no preventive measures in place in the above mentioned two countries (Wikipedia contributors, 2007).

The dying of other aquatic organisms means that the aquatic ecosystem is disturbed because of the reduction in the quality of water. The reduction of the quality of water will also affect the livestock and People living around the affected areas. This is because in some parts of the globe, People are still dependent in water from the rivers. If the livestock are infected with diseases, this may also affect People feeding in the meat of those animals. The other problem in which water hyacinth possesses is that the species acts as a vector in which Mosquitoes build their nests. This means that Mosquitoes will be able to carry their diseases (Malaria) to the People who are living near to the area where the plants are available (Wikipedia contributors, 2007).

Water hyacinth forms fibrous roots which are thick, branched and dark in colour under the water. On top of the water, the species forms a thick mat which prevents many water activities such as swimming, fishing and canoeing. When the species dies, decomposers such as bacteria and fungi are responsible for the decaying of the dead organic matter. The dead organic matter provides other aquatic organisms in the water with food.

REFERENCES

Coetzee, J. 2000. Animals, Plants and the Environment [Online]. [cited 2007 January 18]. Available from: http://sunsite.wits.ac.za/ape/hyacinth.htm

Wikipedia contributors. Water hyacinth [Online]. Wikipedia, The Free Encyclopedia; 3 January 2007, 09:23 UTC (cited 2007 January 23]. Available from:
http://en.wikipedia.org/wiki/Water_hyacinth

Peter Muvhali
CSIR PTA
0001
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URL:http://blogsoccer-peter.blogspot.com

RED DEER AND ITS THREATS TO NATIVE SPECIES

2007-01-24T16:23:00.000+02:00

Red Deer (Cervus elaphus) is indigenous in Britain but its ancestors are originally from Asia. Red Deer are found in the North West Africa, Asia, North West America, Western Europe and Western China (Wikipedia contributors, 2007). The lifespan of the Red Deer is approximately 25 years. The species is non-indigenous in Argentina and New Zealand. Red Deer is described as a large mammal which is dark red in colour which changes to brown in winter with even-ungulates because of the two toes (Clutton-Brock, Coulson and Milner, 2004). Red Deer are well adapted in New-Zealand while in Africa the population is faced with the extinction.

The species is regarded as one of the dangerous alien species in Argentina because of its negative impacts in the indigenous animals. The species out compete indigenous animals for food. In Scotland, Red deers are preventing the regeneration of the woodlands; this is because the number of Red Deers is in the rise and this can lead to the extinction of the woodlands. Red Deer live in woodlands and swamps of the coniferous forest. Red Deers are accused of spreading diseases to indigenous animals (Senseman, 2002). The diseases which the Red Deer spread include meningeal worms and bovine tuberculosis. The species are also accused of out-competing the native animals because of overbrowsing. Some of the farmers regard the Red Deer as pests because of overbrowsing of their cultivated plants which lead to the loss of production and cause soil erosion when there is precipitation. Red Deer provides people with teeth, food, fur and antlers (Senseman, 2002).

Red Deers feed on leaves, twigs and lichens during winter. The species is recognized by means of its stags. After two years, stags start to make branches that develop into antlers. The components of antlers include solid bones which become shed during April and March. The skin develops all around the solid bones with the blood vessels supplying the blood. The supply of the blood is ended after the antlers grow to its full size. Red Deers create important changes in the structural components of the indigenous ecosystem (Moore, 2005). The regeneration of the forest is also inhibited in the area of low density because of these giant animals.

REFERENCES

Coulson, T.; Clutton-Brock, T. H.; and Milner, J. M. (2004). Red deer stocks in
Highlands of Scotland [Online]. [cited January 23, 2007]
Available from: http://www.nature.com/nature/journal/v429/n6989/full/429261a.html

Moore, A. B. 2005. Alien invasive species: Impacts forests and forestry [Online]. [cited 19 January 2007]. Available from: http://www.fao.org/docrep/008/j6854e/J6854E00.HTM

Senseman, L. R. (2002). Cervus elaphus [Online]. [cited 18 January 2007]. Available from: http://animaldiversity.ummz.umich.edu/site/accounts/information/Cervus_elaphus.html

Wikipedia contributors. Red deer [Online]. Wikipedia, The Free Encyclopedia; 21 January 2007, 09:23 UTC (cited 2007 January 23]. Available from:
http://en.wikipedia.org/wiki/Red_Deer

Peter Muvhali
CSIR PTA
0001
Tell no: 012 8142133
Fax: 012 8423676
E-mail: smuvhali@csir.co.za
URL:http://blogsoccer-peter.blogspot.com

BINNS ET AL. (2001) WORKING FOR WATER PROGRAMME IN SOUTH AFRICA

2007-01-24T16:21:00.000+02:00

This is a review of the paper written by Binns [1], water shortage, deforestation and development. The growing and increase of alien plants species in South Africa as a whole causes a serious threat to water supply. Aquatic plants, Herbs, Veins, Shrubs and Trees are the most invasive alien plant species that consume more water than the original plant species. Most of the alien plant species mentioned above are spread in seeds by means of birds and flooding. Aquatic (Eurasian milfoil) grow by forming floating mats of vegetation on the surface of water and it is spread by means of seeds [2]. These species causes a threat to biodiversity, to water security and ecological functioning of natural system.

Working for water (WFW) programme is in partner with organisations such as Councillor for scientific and industrial research (CSIR), Department of water affairs (DWAF) and Department of environmental and tourism (DEAT). This programme was first introduced into SA by the South African government (DEAT) in 1995. The main aim of this programme was to recover scarce water, to conserve biological diversity and to create jobs to disadvantages community. More than 42, 000 people are employed for this programme with and without skills. [3]

Policies and legislation support the WFW. The National Water Act (36 of 1998) supports the WFW. This Act states that “No person may unlawfully and intentionally or negligently commit any act or omission which detrimentally affects or is likely to affect resources” and therefore failure to comply with the Act lawful actions will be taken. The National Environment Management Act (107 of 1998) also supports the WFW programme in terms of pollution. This Act require “the prevent pollution, ecological degradation, secure ecologically sustainable development, use of natural resources while promoting justifiable economic and social development” [4]

In conclusion: Invasive alien species causes water supply problem to the country as whole and the shortage of water in South Africa also causes by unreliable rainfall. The WFW (working for water) programme must continue to remove the alien plants species and alien plants species must be stopped into South Africa.

References:

1. Binns J.A, Illgner and Nel E.L. Water shortage, Deforestration and development: South Africa’s working for water programme, [Internet]. Available from:
http://planet.uwc.ac.za/nisl/invasives/Assignment1/Binns.pdf
2. Remaley T. Great Smoky Mountains national park. [Internet]. Available from:
http://www.nps.gov/plants/alien/fact/mysp1.htm
3. Lois S. Working for Water: Removing Alien Plants in South Africa. [Internet]. Available from: http://www.idrc.ca/en/ev-5156-201-1-DO_TOPIC.html
4. Constitution of South Africa. White paper on a national water policy for South Africa. [Internet]. Available form:
http://www.dwaf.gov.za/Documents/Policies/nwpwp.pdf

Ramapulana Nkoana
CSIR Pretoria
0001
Cell:+27 73 347 6551
Tell:+27 12 841 2133
Fax:+27 12 841 4405

Email: pnkoana@csir.co.za
: puli.nkoana@gmail.com
My blogger URL: http://pnkoana.blogspot.com

Salvinia molesta

2007-01-24T16:14:00.000+02:00

Salvinia molesta is a scientific name for Kariba weed. Salvinia molesta was originally from Brazil and it is well known as a free-floating water fern. This species was found in the Zambezi River in Africa in about 59 years ago. Salvinia molesta has also invaded other countries around the world.

Department of the environment in Australia describes Salvinia molesta as a free-floating rapid-growing, mat-forming, annual fern; individual plants up to 30 cm long with numerous leaves. At the early stage the species leaves lie flat on the surface of the water and at the late stage the leaves bend at the edges, this features distinguishe S. molesta from S.minima. Salvinia molesta can grow rapidly (double within one week) to cover the entire water surface with a thick mat of vegetation. Salvinia molesta causes a great impact in aquatic environment and local economics. It affects the aquatic environment by preventing atmospheric oxygen from entering the water by doing this, it makes the water unfavourable for aquatic animals and it also reduces biodiversity of wetlands. It also dangerous to people since it “provide an ideal breeding environment for disease-carrying mosquitoes” [1]. In Senegal River, Salvinia molesta cause a threat to the biodervisity of the ecosystem conserved by Djoudj National Park.

Salvinia molesta spread quickly in a favourable condition and in size can double almost every two days. It spreads it selves during flooding and by human activities into new catchments. This species can leave under frozen temperature and on the water temperature up to 43°C. It can also survive under a dry condition.

The Australian Government, Department of the Environment and heritage suggested the better method for preventing the spread of Salvinia molesta since is a threat to the biodiversity, the public must be educated not to spread invasive species deliberately and “monitoring should be undertaken in catchments at risk from salvinia invasion” after floods [2].

References:

1.Unknown. Salvinia molesta, Weeds of National Significance: Weed management guide. Department of the Environment and Heritage and the CRC for Austrialian Weed Management, 2003. [Internet] Available from: http://www.deh.gov.au/biodiversity/invasive/publications/s-molesta.html
2. Cronk Q.C and Fuller J.L (1995). Plant invaders. Champman and Hall. [Internet]. Available from
http://www.hear.org/pier/species/salvinia_molesta.htm

Ramapulana Nkoana
CSIR Pretoria
0001
Cell:+27 73 347 6551
Tell:+27 12 841 2133
Fax:+27 12 841 4405

Email: pnkoana@csir.co.za
: puli.nkoana@gmail.com
My blogger URL: http://pnkoana.blogspot.com/

GLOBAL CHANGE AND BIOLOGICAL INVASION

2007-01-24T15:51:00.000+02:00

The global change and biological invasion are currently the main topics in ecology around the world. Global change and biological invasion is a world wide problem. Both are said to have environmental and communal inference. Different studies suggest that Climate change which is caused mainly by human activities may directly or indirectly aid the success of the biological invaders. [1]

Global change includes numerous environmental and ecological alterations that occurs world wide. It includes change in ecology and environment as well as climatic composition of the atmosphere. Biological invaders are referred to plant and animal species not endemic to the particular country. [2 and 3]

Rising in the atmospheric Carbon Dioxide (CO2) plays a role in the success of many invaders. According to Dukes and Mooney 1999, there is a positive respond by invasive plants where CO2 is prominent. For example, the lantana camara which is an indigenous in the south and Central America is known to have tolerance in many environmental conditions even where CO2 is increased. The Bromus rubens grass is known to grow where there are warmer climates and they are favoured by increased CO2. They are well adapted to fire and they increase their dominance where fire occurred [1]. According to the GISP the effects of invasive alien species are worsened by global change and chemical and physical disturbance to species and ecosystems [4]

Land use change is also playing a role in the increase in success rate of the invasive species. In disturbed such as farming areas and disturbed areas for development is more prone to invasion. Most invasive species have competitive capabilities and they can grow and reproduce faster than the native species. The lantana camara are able to release chemicals that prevent other plant species from growing. This process is known as allelopathic mechanism. The lantanas are able grow forming a dense thickets which also prevent other from growing. [1 and 4]

Different studies show that there evidence that global change is playing a role in biological invasion and global change. It is how ever recommended for more studies to be done on global change and biological invasion. More observational and experimental studies must be undertaken to deal with this problem.

Reference:

1. Dukes JS and Mooney HA. 1999. Does global change increase the success of invaders? Trends Ecol Evol 14: 135-39.
2. Wikipedia contributors. Global change [Internet]. Wikipedia, The Free Encyclopedia; 2006 Jun 11, 19:53 UTC [cited 2006 Jul 11]. Available from: http://en.wikipedia.org/w/index.php?title=Global_change&oldid=58080847.
3. Wikipedia contributors. Invasive species [Internet]. Wikipedia, The Free Encyclopedia; 2006 Jul 9, 04:21 UTC [cited 2006 Jul 10]. Available from: http://en.wikipedia.org/w/index.php?title=Invasive_species&oldid=62830037
4. GSIP. Africa invaded: Lantana [Internet]. [Cited 2007 Jan 24]. Available from
http://www.gisp.org/casestudies/showcasestudy.asp?id=57&MyMenuItem=casestudies&worldmap=&country=

Mr Lufuno Mukwevho
CSIR Pretoria
P.O. Box 395
Pretoria, 0001
Tel: (012) 841 2133
Fax: 012 842 7024.
Cell: 0723175626
E-mail: lmukwevho@csir.co.za

ACACIA MEARNSII IS A THREAT TO SOUTH AFRICA

2007-01-24T15:47:00.000+02:00

South Africa is facing a loss of biodiversity caused by the Invasive alien species. Invasive alien species is species introduced to a certain area where they never occurred before and have negative impacts to that area. Invasive alien species has the ability of harming the environment or human health. These species includes plants, animals, microbial and microscopic species [ISAC 2006].

Acacia mearnsii is a threat to South Africa. This alien invasive species is native in Australia and were introduced in South Africa 154 year ago [De Bakker 2003]. Acacia mearnsii is known as the Black Wattle Tree. This species can grow between five to ten meters in height [Anon 1999].The seeds of Acacia mearnsii are dispersed by cattle, birds and water. Birds and water can disperse seeds faster for long distance compared to the cows. This species reproduce through coppice of the seeds because they are small enough to be dispersed.

Acacia mearnsii outcompete native plants for water, nitrogen and organic materials. Acacia mearnsii has a potential of reducing the catchment water yields. Dye and Jarmain (2004) conducted a study in 2004 at Western Cape (Wellington and Groot Drankennstein) and KwaZulu- Natal (Seven Oaks) about water use by Acacia mearnsii. They discovered that Acacia mearnsii use 7mm of rainfall per day and they estimated additional loss of 185 mm of rainfall used annually by Acacia mearnsii. Therefore, each species use the total amount 2740 mm of rainfall annually. I can imagine if ten species are found in one area. South Africa as a water scarce country is faced with the challenge of the spread of Acacia mearnsii, especially the planners, manager and the policy makers that have to come up with the strategies of how to control the Acacia mearnsii species [Dye and Jarmain 2004].

This species provides wood for fuel especially, in the rural areas. Acacia mearnsii prevent erosion because it consists of the long roots that hold the soil particles together. Rouget et al (2002) indicated that Acacia mearnsii and Pinus species “occupy 60% area under commercial plantation and 54% of the area invaded by the alien trees and shrubs”.

However, Acacia mearnsii is a threat; it also provides a good commercial product, Soft – leather, building houses, fencing, electric poles, as woods, etc. The cutting of this species is of importance for commercial use and to save the little water that we have in South Africa.

References:

Anonymous. 1999. Acacia Mearnsii. Available from: http://www.hear.org/Pier/species/acacia_mearnsii.htm.

De Bakker L. 2003. Combating the aliens. Radio Netherlands, Science Unit. Available from: http://www.radionetherlands.nl/features/science/030825alien.html

De Wit M.P, Crookes D.J and van Wilgen B.W. 2001. Conflicts of interest in the environmental management: estimating the costs and benefits of a tree invasion. CSIR Division of water, Environment and Forestry Technology. P167-169.

Dye P. and Jarmain C. 2004. Water use by black wattle (Acacia mearnsii): implications for the link between removal of invading trees and catchment streamflow response. CSIR Division of water, Environment and Forestry Technology. P 40-43.

ISAC (Invasive Species Advisory Committee). 2006. Invasive Species Definition Clarification and Guidance White Paper. Available from: http://www.invasivespeciesinfo.gov/docs/council/isacdef.pdf

Rouget M, Richardson D.M, Nel J.L and Van Wilgen B.W. 2002. Commercially important trees as invasive aliens – towards spatially explicit risk assessment at a national scale. Institute for Plant Conservation, Botany Department, University of Cape Town. P 397 – 398.

Image Credits

http://www.hear.org/starr/hiplants/images/thumbnails/html/acacia_mearnsii.htm

Ms Evelyn Maleka
CILLA CSIR
P.O. Box 395
Pretoria,
0001
Tel: (012) 841 2133
Fax: (012 )841 4405
Email: emaleka@csir.co.za
http://malekaevelyn.blogspot.com/

ECONOMIC EFFECTS OF INVASIVE ALIEN SPECIES

2007-01-24T15:43:00.000+02:00

According to the report by global invasive species programme (GISP) 2003; invasive alien species are posing a serious threat to the world economy. From the ecological point of view, this problem is affecting the biological diversity resulting to its reduction. The most valuable agricultural systems which people depend on for food production are also affected. [1]

Invasive alien species are continuing to pose some negative impacts on the economy through-out the world. The invasive alien species is a problem threatening the value of biodiversity in South Africa. The proliferation of weeds has brought many problems in valuable farming lands. Weeds are opportunistic plants that take advantage of the manipulated agro ecosystem environment to grow and reproduce rapidly. While growing they exert competitive pressure on crop plant [2]. The quantity and quality of crop yields are reduced. Example the kariba weeds (Salvinia molesta). A Kariba weed is a water floating fern and it is native to Brazil. These directly affect the production of foods. [1]

The kariba weeds affect the agricultural sectors in many ways such as blocking the water pipelines, irrigation schemes and other water ways. Harmful aquatic organisms including bacteria and viruses [1] are discharged from the ballast water. Commercial fishing industries are affected hence result to decrease in the economy. [1]

In South African cape floral kingdom, the establishment of weeds decreases the supply of water to the surrounding communities and threatens the native biodiversity [1]. This resulted to the government spending millions of rands on manual and chemical control of the invaders [1]. The invasive are said to have the indirect consequences to the environment which increase the cost for management and prevention. Invasive may cause changes in nutrients cycling, hydrological cycle etc [1].

In many parts of Africa, food production is affected by invasive alien insect’s pests. The white cassava (manihot esculenta) meal bugs are serious threat to agricultural sectors. The invasive weeds make it difficult to restore land for future use because they are able to grow faster. Weeds increase the risk of fire because when they dry-up, the area become prone to fire. Increase in fire result to changes in soil chemistry where it becomes uninhabitable by other by other types of plants [1]. The water hyacinth ( Eichhornia crassipes)uses enough water resulting to competitions between the native plants and the invaders. The invasive are able to with stand and survive until they out compete the native species. [1]

In agricultural sectors, this is costing a lot of money for government around the continent. The current situations indicate that there is a serious threat by the alien invasive species. Much need to be done in order reduces this problem. More efforts on eradication and prevention need to be strengthened.

Reference:

1. GSIP. Africa invaded: Lantana [Internet]. [Cited 2007 Jan 24]. Available from
http://www.gisp.org/casestudies/showcasestudy.asp?id=57&MyMenuItem=casestudies&worldmap=&country=

2. Wikipedia contributors. Weed [Internet]. Wikipedia, The Free Encyclopedia; 2007 Jan 21, 09:14 UTC [cited 2007 Jan 24]. Available from: http://en.wikipedia.org/w/index.php?title=Weed&oldid=102182870.

Mr Lufuno Mukwevho
CSIR Pretoria
P.O. Box 395
Pretoria, 0001
Tel: (012) 841 2133
Fax: 012 842 7024.
Cell: 0723175626
E-mail: lmukwevho@csir.co.za

THE NEGATIVE IMPACTS OF CHROMOLAENA ODORATA ON THE ENVIRONMENT

2007-01-24T15:30:00.000+02:00

I would like to share with you the little information I gathered on C.odorata species. The C. odorata species originates from South and Central America has different common name; Siam weed, or Ortriffid. In its native environment it occurs as a dense “thicket forming” shrub which prevent the establishment of other species. C. odorata is a perennial shrub that can grow up to the height of 3m. However, if growing as climber, it can reach the height of 10 m owing to its fast growing behaviour of 20mm per day.

The C. odorata consist of a single stem with branches growing in pairs to form auxiliary buds. It produces white flowers that contain small seeds of about 3 to 5mm long every year. As it forms a dense thicket, it reduces the level of biodiversity thereby suppressing the growth of young trees. The seeds of C. odorata species can disperse for long distances with its transport media being wind, water, humans, machinery and vehicles. It has relatively large seeds bank longetivity.

The C. odorata is easily propagated from root fragment, stem and from seeds (King and Robinson, 2006) and it preferably grow in open freely-drained ground area with annual rainfall of more than 1200 mm (King and Robinson, 1997). C. odorata can grow in many different types of soils. It prefers to grow in well-drained soils and can not survive on moist and saline soils. The C. odorata has short juvenile period. The C. odorata may also occur in disturbed areas, agricultural areas, planted forest, and also in riparian zones but can not tolerate shade.

This species was introduced in Africa and in tropical regions of Asia where it became a problem, as it is considered a very invasive weed in subtropics and in humid tropics of the world. The species is non-indigenous in India, Africa, Indonesia, Sri Lanka, Malaysia and Indochina (Leslie, 2001).

In South Africa, this species was first observed in the province of Kwazulu Natal. The transport media of this plant is likely water and machinery as it resulted from the materials of packaging that were contaminated when offloaded from the ships at Durban harbour. The date in which the species was first introduced is still unknown. In 1986, C. odorata invaded other parts of provinces and countries such as Limpopo, Eastern Cape, Mpumalanga, Botswana, Mozambique, Zimbabwe and Swaziland (Leslie, 2001).

The C. odorata became a serious invader in South Africa. It possesses a major threat to agriculture, Conservation and forestry. C. odorata can easily invade the riverbanks, as a result destroying habitats of other species. For example, In South Africa, C. odorata destroyed the nests of crocodiles in St. Lucia Lake.

It is taken as a serious invader in South Africa as it is perennial and fast growing plants. The C. odorata is a major threat in South Africa because its seeds are spread rapidly over a long distance. The problem with this species is,it destroy South Africa vegetation.

The handpulling method can be used to mitigate the spread of this species, more especially in young plants. Herbicides can also be used in order to kill the mature C. odorata species. Annual burning regimes can effectively controls the invasion of C. odorata. This is because fire would kill the mature plants and prevent new seedling from establishing. Biological control may also be used.

References

King R.M and Robinson H. 1997. Chromolaena odorata [Online]. [Cited, 22 January 2007]. Available from: http://www.bangor.ac.uk/~afs101/iwpt/web-sp4.htm

King. R.M. and Robinson. H.2006. Chromolaena odorata [Online].[Cited, 23 January 2007]. Available from: http://www.hear.org/Pier/species/chromolaena_odorata.htm

Leslie, J.A. 2001. Chromolaena story, [Online]. University of Stellenbosch, South Africa. [Cited, 21 January 2007]. Available from:http://www.issg.org/database/species/ecology.asp?si=47&fr=1&sts

Linette Netshiheni
CSIR Pretoria
0001
Cell: 0820446442
Tell: 012 841 2133
Fax: 012 842 3676
tnetshiheni@csir.co.za
Weblog: http://tnetshiheni-linette.blogspot.com/

NEED OF CONTROLLING LANTANA CAMARA INVASION IN AFRICA.

2007-01-24T15:17:00.001+02:00

Lantana camara is an indigenous plant of South America. [1] The species was introduced in most of the country as ornamental plant. It has been declared invasive in most part of the world. The invasiveness of lantana camara has also been recognized in African continent. The invasion of lantana camara in Africa need attention as it has economic and social impact, which is influencing poverty in the continent.

The Lantana camara grows as weed in a thicket forming shrub that can spread to various environment. The leaves of Lantana camara are rough and hairy with aromatic smell when grind. [4] It flower grows in on the axils near the stem. [4]The flowers have various colours, it starts to bear flower with pale colour and change to orange when they are old. The fruits of lantana camara look like berry, the fruit contain one seeds. [4] In some parts of the world, lantana camara fruits are eaten and it is palatable to some animal especial goat.

The Lantana camara grows in high rainfall areas, in areas with tropical temperature. The species grow in organic soil, this tend to make it easy to invade sub Sahara regions. The species invade disturbed area like cultivated area. Its habitant of lantana camara includes range land, waste place and near the fence. In most of the African continent, the species was introduced for ornamental purpose and it then spread. [4]

The lantana camara spread more easily, through vegetative reproduction. [4] Where stem sends shoots it o the soil, allowing it to form dense stand and spread. [4] It also spread through pollination where birds and other animals carry seeds for long distance. [4] The ability of lantana camara to colonise area easily is because it can release chemicals in it surrounding that can prevent germination and growth of other plant species around.[2]

In African continent, the management of lantana camara need to be taken into consideration. It brings confusion in the context of alien species, this because it cannot be considered invasion in the country side of Africa. Some animal and people ate its fruits and it cannot be seen as alien invasion in the country side of African continent. In India, it has been used as herbal medicine; it can also be used as fuel wood. [3]

The invasion of the lantana camara has social and economic impact, which needs to be controlled mostly in Africa. It invades cultivated land, in which it releases chemicals to make it difficult for the growth of other plant. [2] This tends to reduce the crop production in Africa. This is because the herbicide control is expensive, the disadvantage group cannot afford to use it to control the spread of lantana in their farms. [2]

The use of other alternative method to control lantana camara can also have impact on our biodiversity. [2] Methods such as fire and physical control can influence the introduction of other alien species. fire burn the species and allows regeneration, whichmake it easy of invasion of new species. [2] This method need to be used with more attention of its advantage of introducing new species.

In general, the invasion of lantana camara in Africa has influence on reducing crop production. It also affect the animals stock, this because lantana camara have toxic chemicals that can affect animals. [4]

Reference:
1. Global invasive species program, 2003. Africa Invaded: Lantana [Internet] Cited 2006 Jan 24 Available from:
http://www.gisp.org/casestudies/showcasestudy.asp?id=57&MyMenuItem=casestudies&worldmap=&country=

2. Verbenaceae L. 2007. Pacific Island Ecosystems at Risk (PIER): Lantana camara
[Internet] Cited 2006 Jan 24 Available from:
http://www.hear.org/Pier/species/lantana_camara.htm

3. Global invasive species Database, 2006. Lantana camara (shrub) [Internet] Cited 2006 Jan 24 Available from: http://www.issg.org/database/species/ecology.asp?si=56&fr=1&sts=

4. Weeds of National Significance: Weed Management GuideDepartment of the Environment and Heritage and the CRC for Australian Weed Management, 200. Lantana (Lantana camara) [Internet] Cited 2006 Jan 24 Available from:http://www.deh.gov.au/biodiversity/invasive/publications/l-camara.html

Mr Elelwani Muanalo
CSIR Pretoria
NISL- Ecological Informatics
Email: emuanalo@csir.co.za
Blogger url: http://muanalo.blogspot.com/

WATER HYACINTHS THREATENS SOUTH AFRICAN MARINE SPECIES

2007-01-24T14:11:00.000+02:00

Water hyacinth (Eichhornia crassipes) is native species in the Amazon Basin. Water hyacinth was introduced in South Africa as an ornamental plant. Now the plant has grown out of control causing havoc in South African water systems and killing marine plants. The water hyacinth is regarded as the world’s worst water weed by the IUNC (World Conservation Union), GISP (Global Invasive Species Programme) and Ramsar Convention on Wetlands of International Impotence [1].

When water hyacinth has found suitable grow conditions it can multiply its population every 12 days. Water hyacinth grows best in warm and humid conditions and water with high nutrients levels (especially from animals and human waste and agricultural fertilisers). Water hyacinth flourishes in still water particularly in shallow water because in open rivers it is washed away by floods. Water hyacinth can get rooted in the soil, flower and produce seeds. Its seeds can last up to 15 years and germinate when the conditions becomes favourable. Most of the indigenous plants are found in shallow water [1].

Water hyacinth forms floating mats on top of the water which obstruct the flow of water and shipping. The water hyacinth forms dense colonies at the edge of lakes, rivers and they smother indigenous species. Water hyacinth clogs the waterways and kills indigenous species by cutting off the sunlight and oxygen [1]. Water hyacinth also makes it for rural people to fetch water and fishing in the rivers.

Scientists discovered five different types of tiny bugs also from the Amazon so that they can kill the water hyacinth since the bugs feed on the water hyacinth in the Amazon. The bugs included the two beetles (Neochetina eichhorniae and Neochetina bruchi) which eat the leaves and crown of the water hyacinth and a mite (Orthogalumna terebrantis) which extract feeding galleries between the leaf veins. A moth’s (Niphograpta albiguttalis) larvae feed on the leaf surface and burrow into the crown of the plant. Lastly is the mirid (Eccritotarsus catarinensis) which extract chlorophyll from the leaves which causes water hyacinth to be brown [2]. Then the plant dies.

The bugs do not kill all the water hyacinth but it reduces the number of the plants from being invasive so that they can be controllable. The bugs are effective but consume a lot of time. The chemical method was also applied but the problem with it is that chemicals kill the bugs, indigenous species without killing the water hyacinth.

Although the scientists have found a way to end this problem but we are still facing yet another problem because the water hyacinth are exotic also the bugs are exotic. What will happen when all the water hyacinth has been depleted? The bugs will start eating the indigenous species or start being invasive.

REFERENCES

1. Griffith, M. Center for Aquatic and Invasive Plants. Geological Survey and University of Florida. [Internet]. Available from: http://news.nationalgeographic.com/news/2003/03/0303_030303_hyacinth_2.html

2. Langeland, K. Wetlands & Waterways. [Internet]. Available from: https://www.denix.osd.mil/denix/Public/ES-Programs/Conservation/Invasive/wetlands.html

Lethabo Mosomane
CSIR
Pretoria
0001
Tel: 27 12 841 2133
Fax: 27 12 842 3676
mail: lmosomane@csir.co.za
http://lmosomane.blogspot.com/

ALIEN PLANTS SPECIES THAT INVADED ABOUT 50 COUNTRIES IN THE WORLD.

2007-01-24T14:09:00.000+02:00

There are many alien species in our county that and some people were not aware that they are planting invasive alien plants that can poison natural species. Lantana camara is a shrub found in the bush and is native at central and south part of America (1). Lantana camara preferred to grow in fertile soils, where there is enough water and it can survive drought season. The height of Lantana camara is 1.8 metres tall. Lantana camara has opposite leaves that are 5 to 12 centimetres long and the wide ranges from 3 to 5 centimetres. The leaves of Lantana camara also have rounded teeth. The leaves of Lantana camara have sweet smelling and hairs. The stem and leaves of Lantana camara are covered by hairs (2).

The fruits of Lantana camara are greenish-blue to black in colour and they are fresh. Lantana camara has vigour (poison) that kills Herbivores animals (rabbits, cattle, and sheep) feed on its leaves. The vigour can also cause sores at the eyes, mouth, and noise of herbivores animals that feed on its leaves (3).

The research about the invasive alien species is done and the result indicated that South Africa is evaded by over 9000 species (4). The researchers also found the 198 of alien species are invaders species and they caused an ecological threat to native species (1). According to the Eden wildy, about 576 million meters square (m²) alien species invade and replace the native plants in KwaZulu-Natal per year (4). This is too bad because the area will end up dominated by alien species.

Lantana camara is regarded as a major problem and it is not easy to be controlled. Agricultural and natural lands are the most areas that are invaded by Lantana camara. Lantana camara is also a poison to the crops (coffee and bananas). Human, birds and animals have been contributed on speding the weeds accidentaly in KwaZulu Natal. Some people planted Lantana camara at their fence rows not knowing that they are planting a invasive plants. Lantana can cause the death to the native species and people must stay away from them.

Many solutions can be done to control or reduce spreading of alien invasive species in our home and county as a whole. The programme of working for water must organise an environmental awareness campaign to communities. It will help the people who do not know about alien invasive species. Let the community know the danger of the alien invasive species. Landowners must check their land every time. People must carefully clean their cloths after visiting the bush. Medias ( radios, television, and newspapers) can be used to teach people about alien invader plants. Hands can be use to pull the invasive alien species. One can cut down the stem of alien species and apply or spray herbicides on the stem to kill invasive alien species.

References:

1. Eden Wildy. Lantana camara. Alien Invaded Plants.[ Online]. 2006 April 23. [Cited 2007 January 22]. Accessed on: http://www.geocities.com/wessaaliens/species/lantana.htm

2. Anonymous. Lantana camara. Floridata. [ Online]. 2006. [cited 2006 January 23]. Accessed on:
http://www.floridata.com/ref/l/lant_c.cfm

3. Anonymous. African Invaded:Lantana camara. The Global Invasive Species Progamme. [ Online]. 2003. [ Cited 2007 January 22]. Accessed on:
http://www.gisp.org/casestudies/showcasestudy.asp?id=57&MyMenuItem=casestudies&worldmap=&country=

4. Eden Wildy. Lantana camara. Alien Invaded Plants.[ Online]. 2006 April 23. [Cited 2007 January 22]. Accessed on: http://www.geocities.com/wessaaliens/index.htm

Lizzy Maluleke
CSIR PTA
0001
Tell [012] 841 2133

Fax [012] 842 3676

E-mail :mmaluleke@csir.co.za

Weblog: http://mmaluleke.blogspot.com

THE INVASION OF MEDITERRANEAN MUSSEL (Mytilus galloprovincialis) IN THE WEST COASTAL PARK OF SOUTH AFRICA

2007-01-24T13:57:00.000+02:00

The Mediterranean mussel (Mytilus galloprovincialis) is a native species in the Mediterranean Sea, Black Sea and Adriatic Sea. It dominates the out coast of France, Britain and Ireland but still unclear whether it is native to these countries. Mytilus galloprovincialis is dark blue or brown to almost black in colour. It possesses two shells which are equal and quadrangular in shape. (Branch and Stephanie 2004).

In the late 1970s the Mytilus galloprovincialis invaded South African coast. It was intentionally introduced for the purpose of aquaculture. It arrived in South Africa and occupies the Langebaan Lagoon. A Lagoon is a body of water cut off from a large body by a reef, sand or coral. The West Coast national park is a home to the Langebaan Lagoon which is recognised as a RAMSAR wetland site of international importance, and these wetlands are designed like sand beds. As a marine global invader Mytilus galloprovincialis was introduced via marine transport, it has been transported by ship ballast water to South Africa.

The introduced species started to out-compete the indigenous black mussel (choromytilus meridionalis) and also threatens the indigenous Perna perna. Its rapid spread has resulted in a decline of this endemic species. Ironically the Mediterranean mussel has become the stronghold of the mussel mariculture industry in Saldahna Bay.

Mytilus galloprovincialis grow so faster in the Lagoon than native mussels because the Lagoon provides more food which enables it to produce more offspring. The species is more air tolerant and have a reproductive output of between 20% and 200% greater than that of indigenous species. (Branch and Stephanie 2004). The problem with its rapid growth and reproduction is that access faeces are released in the Lagoon; these faeces contain organic material and sulphides which lead to the smothering, lack of oxygen and pollution in the sand beds. This makes the sand beds unsuitable to other species.

According to the studies conducted by Robinson and Griffiths (2002) a comparison was done to investigate the differences between Mytilus galloprovincialis invaded areas and non-invaded areas in Langebaan Lagoon highlighting the effect it has on naturally-occurring communities. Communities in invaded areas differed more importantly from non-invaded areas because the figures were indicating that naturally occurring sandbank communities were being replaced with communities more typical of rocky coasts. To conserve the natural biota of the centre banks the mussel beds should be removed (Robinson and Griffiths 2002).

Mytilus galloprovincialis has not yet completely replaced Perna perna. Since Perna perna occupies the lower shore and Mytilus galloprovincialis occupies the higher shore. It can be concluded through the experiment by Shea and Chesson (2002) that M. galloprovincialis suffers high mortality due to wave action on the low shore especially in monospecific beds. In the absence of strong wave P. perna exclude M. galloprovincialis completely.
Though it is the most dominant mussel species today its introduction has not caused major extinction in South African marine species as compared to other invasive species and it has been widely beneficial as food.

Reference list

Branch, G. M. and Stephani, C. N. (2004). Spatial comparisons of populations of an indigenous limpet Scutellastra argenvillei and an alien mussel Mytilus galloprovincialis along a gradient of wave energy. [Internet]. 22 January 2007, 14:04 UTC [Cited 22 Jan 2007]. Available From:
http://www.nisc.co.za/oneAbstract?absId=993

Department of Environmental Affairs ad Tourism. (1999). Driving forces affecting marine and coastal systems and resources. [Internet]. 23 January 2007, 09:44 UTC [Cited 23 Jan 2007]. Available From:
http://www.ngo.grida.no/soesa/nsoer/issues/coast/driver.htm

Griffiths, C. L. and Robinson, T. B. (2003). Status and Impacts of Marine Alien Species in South Africa. [Internet]. 23 January 2007, 11:42 UTC [Cited 23 Jan 2007]. Available From:
http://www.sgnis.org/publicat/grifrobi.htm

Shea and Chesson, 2002. Community ecology theory as a framework for biological invasion, [Internet]. 22 January 2007, 08:16 UTC [Cited 22 Jan 2007]. Available From:
http://eprints.ru.ac.za/466/01/McQuaid_Will_the_invasive_mussel_Mytilus_galloprovincialis_Lamarck.pdf

Dianah Nangammbi
Cilla CSIR
P.O. Box 395
Pretoria
0001
Tel: +27 12 841 2133
Cell: +27 73 121 3589
Email: dnangammbi@csir.co.za
http://wwwdianah.blogspot.com/

THE AFRICAN GREEN MONKEY

2007-01-24T13:37:00.000+02:00

Cercopithecus aethiops is the species of the class mammalian and order primates. C. aethiops is also known as the vervet monkey. The vervet monkeys weigh between 2.7 kg and 8 kg. This species has a lifespan of 22 years. The vervet monkeys are abundant type of monkeys and found in the large part of Africa. In most cases, they are used as the laboratory animal for testing different drugs if they will work for a particular disease [Matthews and Brandt 2004].

The vervet monkeys live in different types of habitats and amongst human, they prefer to live in riverine woodlands. This animal species are omnivorous animals preferring grass for their diet. However, this species prefer grasses, they also feed on arthropods and small vertebrates like lizards, etc. in order to gain protein in their body [Cheney and Seyfarth 1982].

The movement of vervet monkey is the same in the trees and on the ground. They move quardropedally. The vervet monkey gives birth to one offspring and has a gestation period of twenty-two weeks. The social life of the vervet monkey is different among the males, females, and juvenile males and adult males. The females adult interact with their close relatives and they allow other females to take care of their infant. The juvenile males care for their siblings and adults males does not have interest in the infants [Cheney and Seyfarth 1982].

The vervet monkeys use different types of methods for communication, namely, vocal communication, visual communication and tactile communication. The vervet monkeys can use a vocal communication to alert their members about the predators. This species use visual communication for starring, penile display, head-bobbing etc. The tactile communication includes nose-to-nose greetings. The advantageous method of communication is the vocal method because every monkey can be alert even if the monkeys are not close to each other.

The African green monkey became invasive on the Island because of their cropraiding habitat. It was suggested that this species were introduced by the ships that were running the West African Slave trade. The species were favoured at its invasion because they were not disturbed by anything e.g predators. As a result, they multiplied.

REFERENCES:

Cheney, D.L. and Seyfarth, R.M. 1982. Recognition of Individuals within and Between Free-ranging Groups of Vervet Monkeys. American Zoologist Vol. 22, 519-526.

Matthews S. and Brandt K. 2004. Africa Invaded: The growing danger of invasive alien species Global Invasive Species Programme 2004. Available from: http://www.gisp.org/casestudies/showcasestudy.asp?id=96&MyMenuItem=casestudies&worldmap=&country=

Ms Evelyn Maleka
CILLA CSIR
P.O. Box 395
Pretoria,
0001
Tel: (012) 841 2133/2807
Fax: (012 )841 4405
Email: emaleka@csir.co.za
http://malekaevelyn.blogspot.com/

NEW BABOON SPIDER SPECIES DISCOVERED IN KRUGER NATIONAL PARK

2007-01-18T14:21:00.000+02:00

Martin Paulsen and Ian Engelbrecht have discovered a new species of baboon spider (Ceratogyrus paulseni) at Letaba region of the Kruger National Park. They said that the baboon spider comes from four different genera and it is difficult to tell the genera that the baboon spider may fall into. The baboon spider has a horn on its cephalothorax and the horn is similar to the common horned baboon spider (Ceratogyrus becaunichus). This discovery makes one to think about evolution and whether everything is still evolving. The discovery of the baboon spider forms part of the researches of South African National Survey of Arachnids (SANSA) headed by Dr Ansie Dippenaar-Schoeman of the Agricultural Research Commission (ARC). They are trying to discover and describe an inventory of the South African arachnoid fauna. There about 220 species of arachnoids found in Kruger National Park which are known. Kyle Harris, a C•I•B student is conducting a masters (M.sc) research on the “effects of alien invasive plants on spider assemblages within the KNP” [1].

[1]. http://academic.sun.ac.za/cib/news_new_baboon_spider_species.htm

Lethabo Mosomane

CSIR

Pretoria

0001

Tel:2712 841 2133

Fax: 27 12 842 3676

mail: lmosomane@csir.co.za

http://lmosomane.blogspot.com

CORRECTION FOR CHAPTER 2

2006-10-09T12:50:00.000+02:00

Chapter 2 of this course states "Australian aborigines arrived with the dingo and Polynesians brought pigs, taro, yams, and rats (as stowaways)" between 1500 and 1800 AD. This is factually incorrect (see below). All these introductions took place well before 1500 AD.

The time of the arrival of the first humans in Australia is uncertain (with widely different dates documented using various methods) but is generally accepted to be between 40 000 and 50 000 years before present. Radiocarbon dating has placed many sites at about 38000 BC (i.e. about 40 000 years before present). Thermoluninescence dated some sites in northern Australia to about 48000 BC (i.e. about 50 000 years before present) (1). The first settlers did not introduce the dingo to Australia (2). The dingo (Canis lupus ssp. dingo) is thought to have been introduced from South-east Asia between 3000 BC and 1000 AD by Austronesian traders (2, 3) during a theorized intensification of the hunter-gatherer lifestyle (1). The earliest dingo fossil evidence in Australia dates from about 1500 BC (i.e. the fossil is about 3 500 years old) (2).

Present Polynesian cultures are thought to have developed from the so-called Lapita culture that spread from New Guinea to Fiji, Samoa and Tonga around 1600-1200 BC (4). This ancestral Polynesian culture had pigs, dogs and chickens which they took with them. Crops included taro and yams. The Polynesian rat was probably involuntarily spread by the Lapita peoples (5).

References

(1) Wikipedia contributors. Indigenous Australians [Internet]. Wikipedia, The Free Encyclopedia; Updated 2006 Oct. 5, 04:07 UTC [cited 2006 Oct. 5]. Avaliable from: http://en.wikipedia.org/w/index.php?title=Indigenous_Australians&oldid=79588443.

(2) Wikipedia contributors. Dingo [Internet]. Wikipedia, The Free Encyclopedia; Updated 2006 Oct. 2, 15:04 UTC [cited 2006 Oct. 5]. Avaliable from: http://en.wikipedia.org/w/index.php?title=Dingo&oldid=79048433.

(3) Corbett, L.K. Canis lupus ssp. dingo [Internet]. IUCN 2006, 2006 IUCN Red List of Threatened Species <http://www.iucnredlist.org/>; Updated 2004 [cited 2006 Oct. 5]. Available from: http://www.iucnredlist.org/search/details.php/41585/all.

(4) Wikipedia contributors. Polynesia [Internet]. Wikipedia, The Free Encyclopedia; Updated 2006 Oct. 3, 18:50 UTC [cited 2006 Oct. 6]. Avaliable from: http://en.wikipedia.org/w/index.php?title=Polynesia&oldid=79297561.

(5) Wikipedia contributors. Lapita [Internet]. Wikipedia, The Free Encyclopedia; Updated 2006 Sept. 18, 08:07 UTC [cited 2006 Oct. 6]. Avaliable from: http://en.wikipedia.org/w/index.php?title=Lapita&oldid=76374895.

ROBINSON et al. (2005) MARINE ALIEN SPECIES OF SOUTH AFRICA

2006-08-16T16:35:00.000+02:00

This paper reviews the status of the Marine alien species from the South African coast, and hi-lights the ecological impacts of the alien invasions. The paper also includes for the first time what are known as “Cryptogenic” species, or species seldom seen or observed which are invasive.

This important paper indicates that marine organisms have been both intentionally and accidentally moved all over the world’s oceans since the first navigation of the seas and more specifically the increase in shipping over the last century. This includes the increased use of ballast water by ships, and the dumping thereof in different locations other than the original collection point.

Robinson et al. (2005) directed a survey of the present status of three invasive species that were last assessed 10 years ago. The European shore crab, Carcinus maenas, the Mediterranean mussel, Mytilus galloprovincialis, and the Australian whelk, Bedeva paivae were surveyed.

European shore crabs were first discovered in Table Bay Harbour in 1983, and Robinson et al. (2005) suggest that a previous study in 1990 proposed that the crabs “arrived via fouling of International oil exploration vessels, which had docked in the harbour since 1969.” Robinson et al. (2005) sampled both at intertidal and subtidal levels, and additional searches were implemented beyond the known range of the crab, but in similar appropriate habitat. Where populations were encountered in harbours, the size of the population was estimated using the mark-recapture method, which continued until the recapture rate of marked individuals was larger than 10%. No intertidal range extension for the European shore crab was documented, but the paper indicates the first discovery of this crab in the Hout Bay Harbour, which is further than what is previously suggested in my introductory article. The suggestion for the lack of crabs in intertidal areas, is that they may have difficulty in adapting to inhabitation of wave-exposed areas.

The Mark-recapture experiments indicated large subtidal populations in Table Bay Harbour (133 568 individuals) and Hout Bay Harbour (9180 individuals). It is suggested that the movement of small lobster-fishing vessels between these two harbours facilitated the invasion from the Table Bay Harbour to Hout Bay Harbour. What is interesting is that although subtidal sampling has been done for Saldanha Bay, Robinson et al. (2005) state that no specimens of Carcinus maenas were recorded. The authors indicate their curiosity for the apparent disappearance of Carcinus maenas from this area 12 years after its initial discovery and suggest that its potential for invasion could easily have disastrous impacts on the local biodiversity in Saldanha, however no suggestions are entertained regarding possibilities for their disappearance.

Was it biological? It is doubtful that it is physical since the habitat is very similar to that of Table Bay and Hout Bay, and Robinson et al. (2005) indicates a massive increase in their primary food source along the West coast, the invasive Mediterranean mussel, Mytilus galloprovincialis.

The authors conclude that Carcinus maenas is restricted to harbours and sheltered areas, though in general, the overall prevalence of alien marine species is lower than that of other parts of the world. One possible reason for these statistics is the lack of work that has been done in a predominantly unexplored region of the South Africa coastline where investigations for potential populations of alien species have not been carried out yet. The authors warn that another factor could be the relatively poor development of marine taxonomy, which is an additional limiting factor with only four full-time professional marine invertebrate taxonomists working in South Africa. It is suggested that the number and prevalence of marine invasive species will increase as more investigations are undertaken.

Reference:

Robinson T. B., Griffiths C. L., McQuaid C. D., Rius M. 2005. Marine Alien Species of South Africa - Status and Impacts. African Journal of Marine Science 27(1): 297 - 306.

David Vaughan
Senior aquarist, Quarantine
Two Oceans Aquarium
Cape Town, South Africa
dvaughan@aquarium.co.za

INTRODUCTION: EUROPEAN SHORE CRAB.

2006-08-13T12:19:00.000+02:00

I had been doing some reading about the invasive Green crab or European shore crab, Carcinus maenas that we often encounter in the Cape Town harbour. Apart from the literature searching and all the reading, I decided to do my own investigation right outside the effluent of the Two Oceans Aquarium, outside the seal pool. I used a make-shift piece of nylon netting attached to a piece of string weighted down on one end with a normal-sized fishing sinker. Inside the net I placed four whole defrosted pilchards as bait, and sat back to see what happened. The net sank to the bottom quickly and I began my stopwatch. At each minute passed, I pulled up the net and deposited the crabs into a bucket. I stopped “fishing” after exactly 10 minutes and took the crabs inside the aquarium to be counted. I caught 16 European shore crabs in 10 minutes! That is 1.6 crabs per minute! (See photo).

Now that we have put this crab’s potential into perspective, lets look at a bit of its history and characteristics.

This crab is listed as among the 100 most invasive species in the world. Its carapace length can be up to 6cm long and it has 5 distinct “teeth” along the rim of the carapace by the eyes (Wikipedia.org). The colour of the European shore crab varies from different greens to browns and an orangy-red. It is thought that the various colours are associated with different environmental factors (Wikipedia.org). It can be found down to 60m and on all types of shores from muddy to rocky, but prefers shallower areas (Department of Fisheries, Australia). It can also tolerate a wide range of temperatures (0 to 33 Degrees Celsius) and salinities (4 to 54ppt) (Washington Department of Fish and Wildlife).

According to the Washington Department of Fish and Wildlife, the European shore crab has the ability to learn, to improve “prey-handling skills” while foraging for food. This has resulted in an invasive species, which is faster, more dexterous and can take better advantage of the same resources than our native species, easily out-competing them.

In the crab’s native environment it feeds on mussels of the genus Mytilus, Cockels and Dogwhelks. It is also the intermediate host for the acanthocephalan Profilicollis botulus, which kills eider ducks in Scotland (Washington Department of Fish and Wildlife).

The European shore crab is actually native to the North African coast and the Baltic Sea, as well as Norway and Iceland, but was introduced to the East coast of North America in Massachusetts in 1817 (Wikipedia.org). In Australia it was first reported in Port Phillip Bay in Victoria in the early 1900s (Department of Fisheries, Australia), and invaded New South Wales in 1971 and then parts of Southern Australia in 1976. It reached Tasmania in 1993 (Wikipedia.org).

The European shore crab was first encountered in South Africa in Cape Town harbour in 1983, only 23 years ago! It is now also found in Saldanha Bay and Camps bay (Wikipedia.org). The rate of invasion in South Africa so far has been just over 100km in 23years, or about 4.38km per year.

Suggested control measures

In Massachusetts a bounty was established in 1995 for catching the European shore crab to protect the local ecosystem. According to Wikipedia.org, 10 tonnes were caught.

Potential biological control trials in the United States using the parasitic barnacle Sacculina carcini are being investigated, however the indiscriminate nature of the infestation of the parasitic barnacle suggests that it could impact the local crab populations as well, and this would have to be seriously weighed up before being suggested as a course of action (Wikipedia.org).

One alternative is to exploit the resource of the European shore crab as a source of food. In Ireland, baited creels are used alongside the oyster farms to prevent the damage to the oysters by the feeding crabs, and the crabs are collected once caught and sold for processing into food products. The market is relatively small and uncompetitive since the value of the European shore crab is only about €500 per tonne (Wikipedia.org).

The crabs from the Cape Town harbour were often used as a source of food for the resident Black musselcrackers and Red steenbras in the Two Oceans Aquarium’s Open Ocean exhibit (Predator display), and as a food source for the octopus. The use of this crab as a source of food was ceased after a lab sample indicated that these crabs accumulated heavy metals within their tissues and could be a cause of heavy metal poisoning in our fishes in the long-term. It is therefore suggested that the European shore crab cannot be used for human consumption in South Africa, however, it could possibly be controlled using baited traps or by means of frequent dive teams and physical removal operations sanctioned by Marine and Coastal Management. Of major concern is the recent declaration of Moullie Point as a “Closed Area” under Section 77 of the Marine Living Resources Act (Act 18 of 1988), which states that no Rock Lobsters may be caught in the region 12 nautical miles seawards from the high-water mark. Using baited traps for these crabs may constitute an associated catch of these protected lobsters, and would therefore have to be strictly policed.

David Vaughan
Senior aquarist, Quarantine
Two Oceans Aquarium
Cape Town, South Africa
dvaughan@aquarium.co.za

Picture credits:

All pictures are the property of David Vaughan, Two Oceans Aquarium and may not be copied or used without permission.

References:

Wikipedia contributors. Carcinus maenas [Internet]. Wikipedia, The Free Encyclopedia; 2006 Jul 13, 07:10 UTC [cited 2006 Aug 13]. Available from: http://en.wikipedia.org/w/index.php?title=Carcinus_maenas&oldid=63560398.

Washington Department of Fish and Wildlife: Aquatic Nuisance Species [Internet]. [cited 2006 Aug 12, 11:38]. Available from:
http://wdfw.wa.gov/fish/ans/greencrab.htm.

Australian Department of Fisheries: European shore crab [Internet]. [cited 2006 Aug 12, 12:55]. Available from:
http://www.fish.wa.gov.au/docs/pub/IMPShoreCrab/index.php?0506

INVASION OF THE CRITTERS

2006-08-12T11:03:00.000+02:00

I was reading through some of the material that is posted up on GISP, and since I work in a public aquarium, I decided to harp on the subject of aquatic organisms and their role in invasions throughout the world, but particularly here in South Africa. Additionally, for those who have seen my powerpoint presentation, I will also add some additional information on Whitespot or Cryptocaryon irritans as it is known, to add to my justification of its invasive potential.

For those who have fish tanks at home, or a goldfish in a bowl, or a pond outside…here is some food for thought.

Mouton et al. (2001) Indicated that not only is fish keeping in South Africa a very popular pastime, but the majority of the fishes bought in pet shops around the country are imported from areas such as Brazil, Colombia, Indonesia, Malaysia, Peru, Thailand and Sri Lanka (Moravec et al. 1999). As mentioned in my presentation, the South African Government does not have the resource of enough adequately trained staff to implement and police the requirements of the Agricultural Pests Act (Act 36 of 1983), which states that all imported fishes require a period of quarantine though this responsibility falls on the consignee of the shipment (Mouton et al. 2001).

Did you know that there are no guidelines, protocols or legislation suggesting specific requirements of fish quarantine in South Africa, and that there are only a handful of trained and qualified people in aquatic health management in this country? I have been working in this field for nearly 10 years now, and I have also been involved with my own home aquarium, in addition to having the responsibility of the quarantining for both the Two Oceans Aquarium (at present) and Sea World at uShaka Marine World in Durban (from 2003 – 2005). The loophole which is exploited by the pet-trade industry is huge, though in their defence, I am sure the majority of them would prefer to quarantine their fishes correctly prior to release to the general public, if they had the logistical and technical support to do so correctly.

Did you know that goldfish are Cyprinids, a group of the carp-like fishes of which South Africa boast some unique, rare and protected species found nowhere else in the world? Impson et al. (1999) indicates that the Cape Floristic Region, a special conservation concern, has 19 indigenous freshwater fish species of which 16 of them are endemic, and 15 of these are threatened species. They are all Cyprinids. Mouton et al. (2001) indicates that the common goldfish, Carrasius auratus, can happily survive in the temperate regions of South Africa, taking advantage of the same food source as the native Cyprinids, and in fact, a small population was recently discovered on top of Table Mountain! According to “A Complete Guide to the Freshwater Fishes of Southern Africa,” the book by Paul Skelton, the common goldfish can be found as feral populations in the Cape, Port Elizabeth, Pretoria, Kwazulu Natal, and even in Zimbabwe! Other introduced Cyprinids include the common carp, Cyprinus carpio, Grass carp, Ctenopharyngodon idella, Silver carp, Hypophthalmichthys molitrix, and Tench, Tinca tinca.

What is encouraging is the suggestion to prohibit importation of some of these Cyprinids such as the common carp, Cyprinus carpio, but hang on…the Koi is the same species, only a colourful ornamental version, selectively bred over many generations in Japan as not only a form of art, but a serious source of income and industry today. Aquaculture, which includes the South African Koi industry, is one of the fastest growing industries in this country, and responsible for a steady increase in job-creation…Recently this fired up a heated debate, of which the remnants are still available as sections of e-mail between Prof. Paul Skelton, who has been working with the Government to place invasive species into specific categories such as “regulated by area,” “regulated by activity”, and “under surveillance…” The links to the web pages are as follows, and are of particular interest to read:

http://www.happykoi.co.za/Articles/40%20koi%20to%20be%20banned%20in%20south%20africa%20proposed%20legislation.htm
http://www.happykoi.co.za/Articles/41%20koi%20ban%20in%20south%20africa%20follow%20up.htm

So, is it the fishes themselves that are the problem? The answer is both yes and no. Traditionally we have seen the destruction of aquatic biodiversity and macro and micro-habitat disturbance by alien species such as trout, bass and carp, but only now are we beginning to realise just how destructive our ignorance has actually been. All fishes have co-existed and co-evolved with their own set of parasites which they have acquired a certain immunity towards, to allow them to live relatively harmoniously together in normal circumstances. In parasitology, if a naïve host is infected by a parasite for which there is no associated immunity, the results can be the population explosion of the parasite and the possible destruction of the host population in the long term.

Our common goldfish that we keep in our homes are almost always hosts to the monogenean Gyrodactylus gurleyi, G. kobayashii, G. katharineri, and G. medius. Gyrodactylus, though host specific, have the ability to host-swop and can therefore cause potential problems for native Cyprinids in South Africa, not to mention the risk of introducing various Cyprinid-specific viruses to our endemic populations. Remember, one parasite, Gyrodactylus salaris nearly destroyed the entire Norwegian Salmon industry and is still an important threat today! How many goldfish that have died in their bowls have you flushed down the loo? Where do they go, and what hitch-hikers have you potentially introduced to another area? Food for thought.

Putting things back into perspective again, did you know that because terrapins (freshwater turtles) are known carriers of a type of monogenean infecting the urinary bladder, all transportation of all terrapins must be accompanied by a transport permit issued by Cape Nature Conservation, and, if the origin of a terrapin is not known, but has been an illegal pet in someone’s home for a while, not only can it not be re-introduced into the wild, but it is usually destroyed after it has been confiscated? So then why are fishes not treated with the same level of concern?

Late last year I was literally handed two juvenile Red-eared Sliders, an exotic terrapin from America, which came on holiday with their American owners to South Africa and the Waterfront. The terrible twins were placed in a completely transparent plastic box with a sheet of cellophane over the top as a lid, and managed to walk through customs at the Cape Town Docks without any queries, right up to the Two Oceans Aquarium where they were “donated” because they were not wanted anymore! I am just glad they were not just dumped into a drain somewhere. I contacted Dean Impson from Cape Nature Conservation, who explained that this species was black-listed and highly invasive. Luckily they found a home with an approved keeper of illegal exotics by Cape Nature Conservation.

The marine pet-trade is one of serious concern, but also one of the most important industries dealing with the home aquarist. Not only are diseases a common problem as many home aquarists will bear testament to, but what is not fully understood yet is exactly what the potential for invasion this industry has. Most species of marine ornamentals for the aquarium pet-trade are still wild-caught specimens, which are shipped into the country within 18 to 33 hours after packaging from their locations. Many fishes are pre-sold to customers by business owners before they have even landed in the country, and handed out to the purchaser still neatly packaged in their original bags of seawater from all over the world. Though it could be argued that the fishes are only being introduced into home aquaria, and are therefore of low risk, it is the introduction of exotic aquatic diseases and the potential reservoir effect of these home aquaria that threatens our native aquatic biodiversity. Did you know that a main supplier of marine ornamental fishes is the Far East and Sri Lanka, and that the majority of the species brought into our country (without quarantine) are the same species as those that we find in our marine protected areas on the East coast such as Aliwal shoal and Sodwana bay?

So what exactly is the big deal?

Cryptocaryon irritans, the common marine whitespot parasite is thought to be only one worldwide species without variation. Originally, this parasite was though only to be a tropical parasite, preferring temperatures of 22 – 26 Degrees Celsius. Recent studies have indicated that this Ciliophoran parasite is in fact a worldwide group of strains, and these strains have their own adaptations to their native conditions and hosts. Hirazawa et al. (2003) looked at the affects of disinfection using chlorine, benzalkonium chloride and heat treatment as well as increased salinity for the prevention of the spread of Cryptocaryon cysts or tomonts. In their experiment the Cryptocaryon strain used, hatched on the fifth day at 25 Degrees Celsius. A study in progress at the Two Oceans Aquarium has also recently indicated that the Cryptocaryon found off the Cape Town region prefers colder water to warm water, but can actually increase its rate of host re-infestation in unfavourable (warmer) conditions. The local strain of Cryptocaryon began hatching on the fifth day, however the majority hatch only took place on the twelfth and thirteenth days. If the various regions of the South African coastline can expect to be the habitat of specific associated strains of diseases with their own specific host fauna, what impact would the release or introduction of an infected fish from a home aquarium be to our native biodiversity and intricate host-parasite balance? In a review of the mogenean genus Dendromonocotyle from cartilaginous fishes, Chisholm et al. (2004) suggest that previously though worldwide host species, may actually be host-complexes, and if this is so, it can be expected that associated parasite species could have been overlooked. It is therefore of utmost importance not to assume that by purchasing a fish species known from South African waters, it is a lower risk, or that if it becomes too large for the home aquarium, it can be released into the local ocean.

South Africa requires a similar imports risk analysis for the support of improved legislation and training as that implemented by the New Zealand Biosecurity section of the Ministry of Agriculture and Forestry (2005). This risk analysis indicates a strict ban on the Cyprinids discussed above, which is still under debate in this country, and hi-lights the actual disease concerns and previous invasive introductions. The aquatic pet trade is indicated in this risk assessment as one of the main routes of parasitic introduction.

The list of specific genera and species of fishes admissible to New Zealand, the legislative requirements of quarantine and the actual imporation procedures can be accessed at the following website:

http://www.biosecurity.govt.nz/imports/animals/standards/fisornic.all.htm

Some more invasive parasite examples:

American scientists have discovered an isopod parasite called Orthione griffenis that is destroying the native mud shrimp population in the estuaries of the West coast of the USA. The isopod enters the gills of the shrimp and weakens the shrimp as a result of its feeding habits on the blood tissue. The weakened shrimp cannot reproduce and the population is now in decline. John Chapman from the Oregon Sate University is an invasive species expert who suggests that this isopod parasite is not a native parasite, but could have been introduced to the West coast estuaries through ballast water.

Oysters have been moved around during from one area to another and from place to place all over the world in the name of mariculture for many years. The GISP website article on oysters refers to them as “a kind of sessile sheep” having been moved around for the last 150 years. Through the ignorance of today’s environmental and invasion problems, no prevention of potential oyster diseases was controlled for, and subsequently many different diseases have travelled with the oysters to many regions causing problems in native shellfish populations.
Oyster disease or MSX (Haplosporidium nelsoni) and the microcell disease (Bonamia ostreae), have caused severe problems in shellfish fisheries. A paper by Hine and Jones (1994) identifies Bonamia as primarily parasites of flat oysters, but that Bonamia species are endemic to the Southern Pacific, and make up the natural parasite fauna of New Zealand and Australia. An outbreak of Bonamia in New Zealand was followed by a successful manipulation of the oyster population by dredging a partition between infected and uninfected stock.

In France in 1979, Bonamia ostreae was encountered for the first time in Europe. It spread to various other countries in Europe through the oyster trade and became established in the native populations of bivalves. It is now unfeasible to farm oysters in the affected areas in Europe because of the resultant associated mortality rate of 40% to 60%. A new statement released on 27 July this year by the Fish Health Inspectorate of Scotland explains that this parasite has now only recently been discovered in their native oysters in Loch Sunart. Under the Fish Health Regulations of 1997, the movement of all molluscan is now under strict control. The official notice reads as follows:
“The Fish Health Regulations 1997 No 1881 (as amended) Regulation 14 Notice (No.1) 2006 restricts the movement of any live molluscan shellfish into or out of the designated area without prior consent of Scottish Ministers.
The designated area is the area of water comprising tidal waters (whether forming part of the sea or not) within the seaward limits of the territorial water adjacent to Great Britain, which lies between or within, as the case may be, the limits specified below - The waters of Loch Sunart east of a line drawn south south east from the northernmost tip of Maclean's Nose at NM 532 615 to Auliston Point at NM 546 582.”

The Fish Health Inspectorate is looking at options to eliminate this new outbreak in Scotland.

The monogeneans infesting eels, Pseudodactylogyrus bini, and P. anguillae, were recently discovered on eels in North America, which is the first report of the invasion of these two monogenean species, which are originally from Asia (Hayward et al. 2001). These monogeneans are now infesting the native eel population in North America, and it is suggested in the paper by Hayward et al. (2001) that future invasions of similar parasites of eels could become a reality in other parts of the world.

Similarly, monogeneans found on the skin of an eel species investigated as a possible aquaculture species in Stellenbosch are not native to South Africa (K. Christison pers. com), and in late 2005, a species of anchorworm (Lernaea sp.), which is actually a type of crustacean parasite, was found on a University of Stellenbosch-cultured rainbow trout in the floating cages of Klein plaas dam in the Jonkershoek nature reserve. The significance of this is the fact that firstly, salmonids (trouts and salmon) are not usually known to be hosts of Lernaea sp., but Cyprinids such as the common Carp are known as hosts, and are present in the same dam system, which is fed by the upper Eerste river system. If the Lernaea sp. can infest a salmonid, what potential damage is it doing to the native Cyprinids of the upper Eerste river system and tributaries?

What needs to be done…or is it already too late?

To begin with, legislation cannot be successful without the correct support from trained staff. The South African Government must first put in place measures to train the necessary staff in aquatic health management and the identification of parasitic organisms, with the aid of the available taxonomic keys and of course the correct diagnostic equipment. This would not only provide potential job opportunities in a field which could lend itself to support a growing aquaculture industry, but the support structure for the implementation and policing of legislation would prevent future indiscriminate invasions of parasites.

Evidence needs to be acquired to build a case which would then be submitted to the Governmental Department of Environmental Affairs and Tourism, or the argument that exists now, will continue to provide the opportunity for further procrastination: “We don’t see any invasive parasitic problems in this country…”

All it will take is to prove that Gyrodactylus spp. for example can host switch from one species of introduced Cyprinid to a native species, or, that a known invasive parasite species has been identified and is being harboured in a public aquarium in South Africa. The reciprocal reaction would have to be of a serious nature, or the Governmental Department could be seen to be hypocritical.

New Zealand, I believe has taken the initiative and the authority to control this potential problem. Although there is a ban on the importation of certain Cyprinid species into New Zealand, they do allow the trading and breeding of certain ornamental species, though kept controlled by permits. This is the way South Africa should be looking regarding the Koi industry. It could be argued that the gene pool for the breeding of show-quality Koi would be compromised without the importation of brood stock from Japan or other countries, which could impact the sale of high-end show Koi. More realistically though, this argument is refuted by the fact that fertilised ova from high quality Koi could be shipped to this country to be raised in hatcheries where the fry would be naïve to parasitic infestation. All accompanying water shipped with the fertilised ova would be affectively sterilised after the transfer of ova to the hatchery (as also indicated as a protocol for New Zealand). In fact it can then be argued that it is in fact beneficial and feasible. Equally, the breeding of high-quality Koi in this country does not have to continuously rely on the importation of winning brood stock from overseas, and the breeders need to distinguish between responsible biosecurity for our native biodiversity and their role in this, and managing acceptable profit margins. A balance must be reached, or the Koi industry may run the risk of being seen as income-orientated rather than conservation-orientated. With their support instead of criticism thereof, the Biodiversity Act (2004) can be supported.

Quarantine measures

Quarantine is defined in the dictionary as being a period of isolation for forty days, though this should not be an excuse to include all possible invasive pathogens within the same preventative time frame. Work needs to be done to understand the risks of specific disease-causing organisms that can be introduced with aquatic livestock. Species-specific quarantine regimes need to be implemented using the known information of the biology and ecology of these organisms to be most successful. To achieve an effective quarantine for fishes, Integrated Pest Management (IPM) is the only affective tool. IPM used within a species-specific host-parasite profile, would be most effective in reducing potential invasion risks of parasites, and would also reduce not only the risk of potential medication-resistant strain creation, but reduce the amount of medication or therapies used in total, a general cost saving.

Public aquaria have a responsibility as the perceived “Big Brother” of the aquarium world, to lead by example, and I believe that together with the relevant Governmental Departments, the conservation mandate of public aquaria could be shown to provide potential solutions and even logistical support for the implementation of such a quarantine programme.

David Vaughan
Senior aquarist, Quarantine
Two Oceans Aquarium
Cape Town, South Africa
dvaughan@aquarium.co.za

Picture credits isopod shrimp parasite:

http://oregonstate.edu/dept/ncs/newsarch/2005/Aug05/isopod.htm

Picture credit Bonamia 1:

http://www.ices.dk/marineworld/fishdiseases/map8_5.htm

Picture credit Eel:

http://www.fotograf.nu/special/images/eel.jpg

References

International Council for the Exploration of the Sea (ICESCIEM) [Internet] [cited 10 Aug 06 10:54] Available from: http://www.ices.dk/indexfla.asp

Confirmation of Bonamia in Loch Sunart [Internet] [Cited 10 Aug 06: 11:07] Available from: http://www.scotland.gov.uk/News/Releases/2006/07/27154609

Chisholm L. A., Whittington I. D., Fischer A. B. P. 2004. A review of Dendromonocotyle (Monogenea: Monocotylidae) from the skin of stingrays and their control in public aquaria. Folia Parasitologica 51: 123 – 130.

Hayward, C. J., Iwashita M., Crane J. S., Ogawa K, 2001. First report of the invasive eel pest Pseudodactylogyrus bini in North America and in wild American eels. Diseases of Aquatic Organisms 26; 44(1):53-60

Hines P. M., Jones J. B. 1994. Bonamia and other aquatic parasites of importance to New Zealand. New Zealand Journal of Zoology 21: 49 – 56.

Hirazawa N., Goto T., Shirasu K. 2003. Killing effect of various treatments on the monogenean Heterobothrium okamotoi eggs and oncomiracidia and the ciliate Cryptocaryon irritans cysts and theronts. Aquaculture 223: 1 – 13.

Impson N. D., Bills I. R., Cambray J. A., Le Roux A. 1999. The primary freshwater fishes of the Cape Floristic Region: Conservation needs for a unique and highly threatened fauna. Stellenbosch: Cape Nature Conservation.

Moravec F., Wolter J., Korting W. 1999. Some nematodes and acanthocephalans from exotic ornamental freshwater fishes imported into Germany. Folia Parasitologica 46: 296 – 310.

Mouton A., Basson L., Impson D. 2001. Health status of ornamental freshwater fishes imported to South Africa: a pilot study. Aquarium Sciences and Conservation 3: 327 – 333.

PRESENTATIONS CANNOT BE OPENED

2006-07-20T23:27:00.000+02:00

Hi

I asked for the following....

1) Your Power Point using the NISL-EI2 Template
2) A sound file for each slide.

What you have done is to embed, the sound into the Power Point rather than "make a sound file for each slide" - The result are these HUGE Power Points, and at least one of which is known to be corrupt (L Mosomane). I actually cannot open any of them on my PC as they are too large!

I guess you best put onto a CD, print out the Power Point making sure you use the option that includes the notes attached to the slide and also making sure you print one slide per page. You can print in black and white.

What I had actually wanted was a Power Point and for each slide of the Power Point to have its own sound file. In other words if you had twenty slides, there would be twenty sound files, with say slide 1 having a slide1.avi, slide 2 having a slide2.avi file etc (the extension is dependent on software and could also be slide1.mp3 and slide2.mp3.

The reason I wanted it in the above way was to prevent developing huge files that 500+ MBytes. Please do not redo, but when you put onto the CD check that Power Points open on another machine so that the file is not corrupt.

Again I will be handing this over to an external with the instructions that you were given and a copy of the paper you reviewed.

Please attached your plagiarism statement to your assignment.

Rich

SOME POTENTIAL “WEEDS” WE RECENTLY GAVE TO AUSTRALIA

2006-07-15T17:16:00.000+02:00

We all know about Rooikrans (Acacia Cyclops) and Port Jackson (Acacia saligna) originating from Australia that have invaded many areas in the Cape Floristic Region. Many South African plants have however also become invasive in Australia. Some are even threatened species in their natural habitat in South Africa, but have become a pest in Australia. One such example is the yellow wild iris (Dietes bicolour). South African plants that have long been declared pests in Australia are for example our bitou (Chrysanthemoides monilifera) and arum lily (Zantedeschia aethiopica).

New introductions of potential weeds is however an ongoing problem. Recent South African introductions (between 1971-1995) in Australia that have already become locally naturalized are amongst others the green ixia (Ixia viridiflora), the blouooguintjie (Moraea aristata), a gladiolus from Kwazulu-Natal (Gladiolus natalensis) and a chasmanthe (Chasmanthe bicolour). Yet three of these species are red data species in South Africa! All of the above mentioned plants were introduced as ornamental garden plants but have since escaped from urban gardens and have become naturalized. (read more here)

Up until 2004 non-South African resident members of the Botanical Society of South Africa could make use of the “free seed benefit”. This meant that as members they could order a certain amount of seeds from South African indigenous plants for free on a yearly basis. This was discontinued at the end of 2004. One of the reasons was to stop the spread of potentially alien invasive weeds to other countries.

Australia now has very strict legislation to try and prevent further introductions of potentially invasive species. However, as long as there are obsessed plant collectors willing to pay, seeds and plants will find their way into other countries …

Further reading:

March 2006 issue of Veld & Flora, the Journal of the Botanical Society of South Africa.

South African Red Data List (can be downloaded at the following link: http://www.sanbi.org/frames/infofram.htm )

Karen Marais
BCB Hons NISL student
University of the Western Cape
Private Bag X17
Bellville

E-mail 2657211@uwc.ac.za

Web http://brit-journal.com/karen2006bcbnisl/

NEWLANDS FOREST

2006-07-15T17:13:00.000+02:00

A recent research article in Biological Conservation 132 ( 2006 ) 183 –198 by Alston KP and Richardson DM deals with alien invasive plants in Newlands Forest, Cape Town. The “edge effect” of an urban/wildland interface was studied. They found a significant correlation between the distance from supposed source populations (mainly sub-urban gardens) and alien species richness in different habitats of Newlands Forest as well as a significant correlation between alien species richness and the level of disturbance.

To read more follow the link http://academic.sun.ac.za/cib/publications2006.htm

Karen Marais
BCB Hons NISL student
University of the Western Cape
Private Bag X17
Bellville

E-mail 2657211@uwc.ac.za

Web http://brit-journal.com/karen2006bcbnisl/

CENTRE OF EXCELLENCE FOR INVASION BIOLOGY

2006-07-15T17:08:00.000+02:00

If Invasion Biology interests you, visit the website of the Centre of Excellence for Invasion Biology based at the University of Stellenbosch. I have found this website very informative. There are also links to other sites as well as to recent publications regarding Invasion Biology. Make sure to visit the “Of interest” section for some relevant and interesting recent news in this field.

http://academic.sun.ac.za/cib/

Karen Marais
BCB Hons NISL student
University of the Western Cape
Private Bag X17
Bellville

E-mail 2657211@uwc.ac.za

Web http://brit-journal.com/karen2006bcbnisl/

PRESENTATION DUE

2006-07-09T20:06:00.000+02:00

Hi Everyone

Over a month ago I sent through instructions for the review paper for the Invasion Biology Course, too date I have not received any Power Points, I trust they are completed (including your sound files) so can you please send them to me at knight.rich@gmail.com.

Notification URL sent out in Early June

http://bcb722.blogspot.com/2006/06/please-confirm-your-choice-of-research.html

You should have the Power Point Presentation itself plus your sound files for each slide - can you please zip all files into one file using eithe WinZip on Winrar.

To confirm I need

Your Power Point using the NISL-EI2 Template
A sound file for each slide.
These files zipped into one file and emailed to me

Please confirm that you have completed this or at least provide progress and an intended date to submit, by adding a comment to this POSTING.

Thanks

Rich

Picture Credit

http://www.humordrive.com/presentation-cartoons

ALIEN REPTILES “AN ENVIRONMENTAL PEST” IN AUSTRALIA

2006-07-04T13:06:00.000+02:00

The pet trade in exotic species seems to be a world wide problem. Tortoises and geckos have recently been in the news in South Africa, when foreigners were caught trying to smuggle live animals that they had illegally captured in the wild…

In Australia they have a problem with exotic snakes that are illegally kept as pets and then escape. The Department of Sustainability and Environment (DSE) in Australia has in Victoria alone found 340 “exotic” reptiles over the last four years. Amongst them were 63 corn snakes, native to the United States and Mexico. These snakes were termed as “rabbits of the reptile world” by DSE senior investigator Keith Lanner, because they breed so rapidly.

Apparently the DSE has found a correlation between illegally kept snakes and drug dealing… I found the following passage quite amusing: “A profile compiled by the DSE suggests that a person most likely to be keeping exotic reptiles illegally is: 18 to 35 years old, living in the western suburbs or Geelong, a blue-collar worker or unemployed, licensed to keep native wildlife and a cannabis grower.”

Reports like these just make me wonder when are people ever going to learn? Why are people so obsessed with exotic pets? Without a market there wouldn’t be a trade…

Karen Marais
BCB Hons NISL student
University of the Western Cape
Private Bag X17
Bellville

E-mail 2657211@uwc.ac.za

Web http://brit-journal.com/karen2006bcbnisl/

GISP – A WEBSITE WORTH A WEEKLY VISIT!

2006-07-04T12:01:00.000+02:00

Have you explored the GISP website yet? Well, if you haven’t, do yourself a favour. I have spent many hours browsing the web in search of information on invasive alien species over the past few days and I have to admit this was one of the sites I enjoyed the most… even if I could not find much information on this site on the specific species I had chosen for my Expert System assignment! (At least here were many links that did help me!)

The home page is packed with interesting information. I had to force myself to finish my assignment first, because there were so many interesting snippets that caught my eye that I wanted to read.

Although the global invasive species database only had information on one of the species I had chosen, the information that is available is comprehensive and very useful. (I do hope that this database will be expanded to include as many invasive species as possible.)

Karen Marais
BCB Hons NISL student
University of the Western Cape
Private Bag X17
Bellville

E-mail 2657211@uwc.ac.za

Web http://brit-journal.com/karen2006bcbnisl/

ADDRESSING STUDENT PLAGIARISM

2006-06-25T12:23:00.000+02:00

All Email originating from UWC is covered by disclaimer http://www.uwc.ac.za/portal/uwc2006/content/mail_disclaimer/index.htm

Hi

I received this email from our Director of ICS Prof. Derek Keats on the 06/20/06 07:50AM so I thought you should all review the article referred to.

Please note that I plagiarized this word for word....thought it might be of interest....

"Sally Brown, pro vice chancellor for assessment, learning, and teaching at Leeds Metropolitan University in the United Kingdom, believes that the age of technology has not only made cheating easy but has also engendered a sense among today's students that there is nothing wrong with copying and pasting someone else's work into your own. Many students today, she said, simply do not understand what plagiarism is and why it is wrong. Of the several approaches Brown suggested for fixing the problem, the one she thinks the best is designing coursework around plagiarism. By giving assignments that require personal knowledge or that compel students to provide regular accounts of their studies, an instructor can largely avoid the issue of plagiarism, according to Brown. Other strategies include education, punishments, and changing the culture among students so that cheaters are looked down on by everyone."

BBC, 18 June 2006
http://news.bbc.co.uk/2/hi/uk_news/education/5093286.stm

Derek Keats

I will be putting links up on the finalized documents from the Science Faculty for your attention.

Cheers

Rich

Dr Richard Knight
Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za

Web http://nisl.uwc.ac.za

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za

Web http://nisl.uwc.ac.za

PLAGIARISM PREVENTION, GRADING AND PEER-REVIEW: THE WAY FORWARD

2006-06-07T02:04:00.000+02:00

All Email originating from UWC is covered by disclaimer http://www.uwc.ac.za/portal/uwc2006/content/mail_disclaimer/index.htm

Hi Everyone

I am finalizing the contract with Turnitin so that future assignments for me (viz the NISL-EI2 courses) will require submitting to this electronic scanning service. This is not actually to scare you, rather to help you with your writing skills and get away from a dependency for lifting text from the Internet, printed text and even previous student assignments submitted (your assignments are entered into an electronic database that is used for future scanning). It works in the following way...

There will be a link on each course Blog page to Turnitin for submitting of the assignments.
You will be issued Turnitin accounts (usernames and logins) for the NISL-EI courses.
I will setup the assignment details for your submission.
In the beginning you will be required to create your student profile that will include your ClassID and Password, which I will provide you via email. You will then need to fill in your email address, provide your personal Turnitin password (a minimum of 6 letters and numbers but no special characters and at least one character must be a number), you will then be presented with a secrete password retrieval question and answer and finally to complete your profile you will provide your names (first and last name) and your Country.
The creation of your student profile is completed when you accept the user profile agreement form.
You will then get logged in and will navigate to the correct BCB course and assignment.
You will upload your assignment and you will see that it has been uploaded (you can check that it is the right document via the on screen system) and once confirmed you will get a digital receipt and a confirmation email message that the assignment was submitted and time stamped.
Late assignments will not be accepted via the electronic system.
If you are confused do not worry online training videos will be provided just prior to initiation of this process.

I have elected to go for an electronic marking as well, so your assignment will be analysed first for Plagiarism and if too high will be returned to you with a full report of where there is plagiarism and close paraphrasing. I do not know how strictly this system will apply the rules but certainly just changing a word or two in place will not fool the system and it is based on a very comprehensive database. I will then use my discretion as to whether you get zero marks or a chance to re-submit. Unfortunately the cost of the scanning service is rather expensive and we pay for both an annual subscription and a per document cost, so chances to re-submit will be restricted (each assignment will cost me about R10 to process). An electronic grading will be done and you will be sent back your marked-up scripts with the grade electronically. This system will work much better than the old way of emailing them to my gmail account which I can only access after hours. Finally some assignments will also be peer marked by yourselves using the Turnitin Peer Review system.

Hopefully this will level the playing field and be fair to everyone and was a decision not taken lightly. Until I know when our payments have been made and the Turnitin accounts been set up please hold back from submitting any assignments such as the Biodiversity due at the end of this week. The first assignment that you will be submitting will be your cumulative Biodiversity reports (all of your answers combined into one report to save scanning costs and processing time). Since you have had extensive feedback on these assignments previously it will give us the perfect opportunity to know precisely how the implementation of the system will work.

Can you please confirm that you have read and understood this posting by attaching a comment and your name. This is also an opportunity to air any issues that you have or to finally clear up any misunderstandings, I promise to respond to all of your concerns if expressed.

Good Luck

Rich

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za

Web http://nisl.uwc.ac.za

PLEASE CONFIRM YOUR CHOICE OF RESEARCH PAPER

2006-06-06T09:25:00.000+02:00

Hi Everyone

Please make sure that you have booked your Research Paper for reviewing
and preparing for Power Point by the end of today. Just to remind you
there are two "A" grade papers which if you do you will get 10% bonus
and there are some shorter ones which will only be marked to 90% but are
less work. There are however, at least 10 papers that are B graded
which will be marked out of 100%. Read through the abstracts and then
download the research paper. Once selected confirm by adding your
comment to the appropriate posting.

Cheers

Rich

Dr Richard Knight
Co-ordinator: National Information Society Learnerships - Ecological
Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za

Web http://nisl.uwc.ac.za

TORCHIN ET AL. PLEASE REVIEW

2006-06-06T01:22:00.000+02:00

Parasites and marine invasions

Introduced marine species are a major environmental and economic problem. The rate of these biological invasions has substantially increased in recent years due to the globalization of the world's economies. The damage caused by invasive species is often a result of the higher densities and larger sizes they attain compared to where they are native. A prominent
hypothesis explaining the success of introduced species is that they are relatively free of the eåects of natural enemies. Most notably, they may encounter fewer parasites in their introduced range compared to their native range. Parasites are ubiquitous and pervasive in marine systems, yet their role in marine invasions is relatively unexplored. Although data on parasites of marine organisms exist, the extent to which parasites can mediate marine invasions, or the extent to which invasive parasites and pathogens are responsible for infecting or potentially decimating native marine species have not been examined. In this review, we present a theoretical framework to model invasion success and examine the evidence for a relationship between parasite presence and the success of introduced marine species. For this, we compare the prevalence and species richness of parasites in several introduced populations of marine species with populations where they are native. We also discuss the potential impacts of introduced marine parasites on native ecosystems.

PLEASE REVIEW DAVID'S PRESENTATION (RIGHT UNDER MENU 'STUDENT PRESENTATIONS' AND ADD YOUR COMMENTS TO THIS POSTING. I WILL TRY AND MAKE A PRESENTATION OF RIGHT AND WRONG FORMATTING. PLEASE LOOK UNDER ATTACHMENTS FOR THE NOTES AND THE ORIGINAL PAPER. YOUR PRESENTATION SHOULD LOOK AS IF PREPARED BY THE SAME AUTHOR AND NOTE THAT OTHER PEER-REVIEWED MATERIAL IS PROVIDED!

Cheers

Rich

Dr Richard Knight
Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
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ZAVALETA, HOBBS & MOONEY 2001

2006-06-04T23:24:00.000+02:00

Viewing invasive species removal in a whole-ecosystem context

Eradications of invasive species often have striking positive effects on native biota. However, recent research has shown that species removal in isolationcan also result in unexpected changes to other ecosystem components. These secondary effects will become more likely as numbers of interacting invaders increase in ecosystems, and as exotics in late stages of invasion eliminate native species and replace their functional roles. Food web and functional role frameworks can be used to identify ecological conditions that forecast the potential for unwanted secondary impacts. Integration of eradication into a holistic process of assessment and restoration will help safeguard against accidental, adverse effects on native ecosystems.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Zavaleta.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
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Bellville 7535

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WILES ET AL. 2003

2006-06-04T23:12:00.000+02:00

Impacts of the Brown Tree Snake: Patterns of Decline and Species Persistence in Guam’s Avifauna

Predation by brown tree snakes (Boiga irregularis) devastated the avifauna of Guam in the Mariana Islands during the last half of the twentieth century, causing the extirpation or serious reduction of most of the island’s 25 resident bird species. Past studies have provided qualitative descriptions of the decline of native forest birds but have not considered all species or presented quantitative analyses. We analyzed two sets of survey data gathered in northern Guam between 1976 and 1998 and reviewed unpublished sources to provide a comprehensive account of the impact of brown tree snakes on the island’s birds. Our results indicate that 22 species, including 17 of 18 native species, were severely affected by snakes. Twelve species were likely extirpated as breeding residents on the main island, 8 others experienced declines of >90% throughout the island or at least in the north, and 2 were kept at reduced population levels during all or much of the study. Declines of >90% occurred rapidly, averaging just 8.9 years along three roadside survey routes combined and 1.6 years at a 100-ha forested study site. Declines in northern Guam were also relatively synchronous and occurred from about 1976 to 1986 for most species. The most important factor pre-disposing a species to coexistence with brown tree snakes was its ability to nest and roost at locations where snakes were uncommon. Large clutch size and large body size were also related to longer persistence times, although large body size appeared to delay, but not prevent, extirpation. Our results draw attention to the enormous detrimental impact that brown tree snakes are likely to have upon invading new areas. Increased containment efforts on Guam are needed to prevent further colonizations, but a variety of additional management efforts would also benefit the island’s remaining bird populations.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Wiles.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
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WELTZIN, BELOTE & SANDERS 2003

2006-06-04T23:01:00.000+02:00

Biological invaders in a greenhouse world: will elevated CO2 fuel plant invasions?

Climate change and biological invasions, two of the hottest topics in ecology, both have ecological and societal implications, but they have developed on separate and parallel paths. Both are likely to have global impacts, yet researchers seldom explicitly consider their interaction. We argue that changes in atmospheric concentrations of carbon dioxide (CO2) and subsequent climate change may facilitate biological invasions, both directly and indirectly, and that our research agenda to date has left us poorly prepared to predict the consequences for communities and ecosystems. Forecasting the impact of biological invaders or elevated CO2 is a challenge for ecologists, and it is therefore prudent and timely to investigate the greater challenge, namely predicting the combined effects of invaders and elevated CO2 on native ecological systems.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Weltzin.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
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VERMEIJ 1996

2006-06-04T22:53:00.000+02:00

An Agenda for Invasion Biology

Here I advocate a comparative and systematic approach in which invasion (the extension of species ranges to areas not previously occupied by that species) is studied from the perspective of individual species as well as of the regions and biotas that export and receive invaders. In order to go beyond the particulars of invasion, it is important to ask: (1) how invaders differ from non-invaders in the arrival, establishment, and integration phases of invasion; (2) how donor regions or communities that have produced many successful invaders differ from those in which few resident species have been able to extend their ranges; (3) how recipient ecosystems with many successfully established invaders differ from those in which few species have taken hold, and (4) how invasion affects evolution not only of the invader itself, but of species in the recipient community with which the invader interacts.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Vermeij.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

SHAPIRO 2002

2006-06-04T22:50:00.000+02:00

The Californian urban butterfly fauna is dependent on alien plants

Using the unusually well-documented butterfly fauna of Davis, Yolo County, California, it is shown that the mainly native species commonly observed in gardens breed mostly or entirely on alien plants, especially naturalized weeds. Over 40% of the fauna has no known native hosts in the urban–suburban environment. Were certain alien weeds to be eradicated or their abundance greatly reduced, the urban-suburban butterfly fauna would disappear. This might be regarded as an unfortunate, and perhaps intolerable, side-effect of such programs.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Shapiro.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

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RICHARDSON & VAN WILGEN 2004

2006-06-04T22:32:00.000+02:00

Invasive alien plants in South Africa: how well do we understand the ecological impacts?

This paper examines the evidence for the effects of invasive alien plants in natural and semi-natural ecosystems in South Africa. Invasive alien plants are concentrated in the Western Cape, along the eastern seaboard, and into the eastern interior, but there is a shortage of accurate data on abundance within this range. Most information on site-specific impacts comes from the fynbos biome, and is generally poor for other biomes. The consequences of invasions for the delivery of ecosystem goods and services to people are, with the notable exception of their influence on water resources, inadequately studied. Our understanding of many of the broader aspects of invasion ecology needs to be enhanced, and we identify important challenges for research to address critical gaps in knowledge. Priorities for future research include the development of a predictive understanding of the rates of spread of invasive alien plants, and the development of achievable goals for ecosystem repair after clearing, including measurable criteria for assessing the success of restoration. Climate change could significantly exacerbate problems with invasive species and work is needed to accommodate plausible trajectories in planning and management frameworks. Perhaps the greatest challenge for South African ecologists is to address the twin issues of skills development and social transformation, to ensure that adequate and relevant ecological expertise is maintained to meet future research and management needs. Formal collaboration between organizations to address capacity building and educational transformation in the field of invasion ecology would represent a significant step forward.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/RichardsonandvanWilgen.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

RICHARDSON ET AL. 2000

2006-06-04T22:03:00.000+02:00

Plant invasions ± the role of mutualisms

Many introduced plant species rely on mutualisms in their new habitats to overcome barriers to establishment and to become naturalized and, in some cases, invasive. Mutualisms involving animal mediated pollination and seed dispersal, and symbioses between plant roots and microbiota often facilitate invasions. The spread of many alien plants, particularly woody ones, depends on pollinator mutualisms. Most alien plants are well served by generalist pollinators (insects and birds), and pollinator limitation does not appear to be a major barrier for the spread of introduced plants (special conditions relating to Ficus andorchids are described). Seeds of many of the most notorious plant invaders are dispersed by animals, mainly birds and mammals. Our review supports the view that tightly coevolved, plant-vertebrate seed dispersal systems are extremely rare. Vertebrate-dispersed plants are generally not limited reproductively by the lack of dispersers. Most mycorrhizal plants form associations with arbuscular mycorrhizal fungi which, becauseof their low specificity, do not seem to play a major role in facilitating or hindering plant invasions (except possibly on remote islands such as the Galapagos which are poor in arbuscular mycorrhizal fungi). The lack of symbionts has, however, been a major barrier for many ectomycorrhizal plants, notably for Pinus spp. inparts of the southern hemisphere. The roles of nitrogen-fixing associations between legumes and rhizobia and between actinorhizal plants and Frankia spp. in promoting or hindering invasions have been virtually ignoredin the invasions literature. Symbionts required to induce nitrogen fixation in many plants are extremely widespread, but intentional introductions of symbionts have altered the invasibility of many, if not most, systems. Some of the world's worst invasive alien species only invaded after the introduction of symbionts. Mutualisms in the new environment sometimes re-unite the same species that form partnerships in the native range of the plant. Very often, however, different species are involved, emphasizing the diffuse nature ofmany (most) mutualisms. Mutualisms in new habitats usually duplicate functions or strategies that exist in the natural range of the plant. Occasionally, mutualisms forge totally novel combinations, with profound implications for the behaviour of the introduced plant in the new environment (examples are seed dispersal mutualisms involving wind-dispersed pines and cockatoos in Australia; and mycorrhizal associations involving plant roots and fungi). Many ecosystems are becoming more susceptible to invasion by introduced plants because: (a) they contain an increasing array of potential mutualistic partners (e.g. generalist frugivores and pollinators, mycorrhizal fungi with wide host ranges, rhizobia strains with infectivity across genera); and (b) conditions conducive for the establishment of various alien/alien synergisms are becoming more abundant. Incorporating perspectives on mutualisms in screening protocols will improve (but not perfect) our ability to predict whether a given plant species could invade a particular habitat. Key words: biological invasions, global change, invasibility, mycorrhiza, nitrogen fixation, pollination, prediction, risk assessment, seed dispersal.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Richardson.pdf

Difficulty A

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape Private
Bag X17
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Fax 27 + 21 + 959 1237

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PETIT 2004

2006-06-04T21:57:00.000+02:00

Biological invasions at the gene level

Despite several recent contributions of population and evolutionary biology to the rapidly developing field of invasion biology, integration is far from perfect. I argue here that invasion and native status are sometimes best discussed at the level of the gene rather than at the level of the species. This, and the need to consider both natural (e.g. postglacial) and human-induced invasions, suggests that a more integrative view of invasion biology is required.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Petit.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

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PETERSON & VIEGLAIS 2001

2006-06-04T21:49:00.000+02:00

Predicting Species Invasions Using Ecological Niche Modeling: New Approaches from Bioinformatics Attack a Pressing Problem

On 3 February 1999, President Clinton signed an executive order dealing with invasive species in the United States. The order was designed to lay the foundation for a program “to prevent the introduction of invasive species and provide for their control and to minimize the economic, ecological, and human health impacts that invasive species cause” (Clinton 1999). This program includes far-reaching plans to prevent, plan, monitor, and study species’ invasions. Such high-level attention emphasizes the enormity of the problem facing the United States, and in fact the entire world: With ever-growing international commerce, reduced barriers to trade, and increasing human influence, species are moving around, and natural systems are suffering drastic changes. The dimensions of the problem are indeed impressive. Alien plants, animals, and microbes have poured into theUnited States from all directions. Natural systems have been disrupted, species extinguished, transportation and agriculture compromised, and resources damaged (Carlton1997–1998, Ogutu-Ohwayo 1997–1998, Richardson1997–1998, Shiva 1997–1998). In fact, most modern agricultureis based on non-native organisms; problems arise because questions of when and why some escape and become nuisances remain unanswered. More generally, no proactive approach to combating such species is available—invasive species are dealt with one at a time, as they become problematic.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/PetersonandVieglais.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

O'DOWD, GREENT & LAKE 2003

2006-06-04T21:42:00.000+02:00

Invasional "meltdown" on an oceanic island

Islands can serve as model systems for understanding how biological invasions affect community structure and ecosystem function. Here we show invasion by the alien crazy ant Anoplolepis gracilipes causes a rapid, catastrophic shift in the rain forest ecosystem of atropical oceanic island, affecting at least three trophic levels. In invaded areas, crazy ants extirpate the red land crab, the dominant endemic consumer on the forest floor. In doing so, crazy ants indirectly release seedling recruitment, enhance species richness of seedlings, and slow litter breakdown. In the forest canopy, new associations between this invasive ant and honeydew-secreting scale insects accelerate and diversify impacts. Sustained high densities of foraging ants on canopy trees result in high population densities of host generalist scale insects and growth of sooty moulds, leading to canopy dieback and even deaths of canopy trees. The indirect fallout from the displacement of a native "keystone" species by an ant invader, itself abetted by introduced/cryptogenic mutualists, produces synergism in impacts to precipitate invasional "meltdown" in this system.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/ODowd.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

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MEYERS ET AL. 2000

2006-06-04T21:36:00.000+02:00

Eradication revisited: dealing with exotic species

Invasions of non-indigenous species threaten native biodiversity, ecosystem functioning, animal and plant health, and human economies. The best solution is to prevent the introduction of exotic organisms but, once introduced, eradication might be feasible. The potential ecological and social ramifications of eradication projects make them controversial; however, these programs provide unique opportunities for experimental ecological studies. Deciding whether to attempt eradication is not simple and alternative approaches might be preferable in some situations.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Myers.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

LeMAITRE 2004

2006-06-04T20:30:00.000+02:00

Alien plant invasions in South Africa: driving forces and the human dimension

Invasive alien plants pose a substantial threat to the rich biodiversityof South Africa, and to the sustained delivery of a wide range of ecosystem services. Biological invasions are driven by human activities and mediated by culturally shaped values andethics. This paper explores the human dimensions of alien plant invasions in South Africa. We consider four primary forces, those which directly influence the likelihood and rate of invasion—arrival of propagules; changes in disturbance regimes; changes in the availability of limiting factors; and fragmentation of the landscape— and the roles of 22 secondary driving forces in shapingthe outcomes of the four primary driving forces. Human societies and their dynamics and activities are an integral part of each of the secondary driving forces. A map of the interactions between and among the primary and secondary driving forces shows how they are interlinked and influence each other—either positively or negatively, or switching between the two. There are two key points for intervention: prevention of the introduction of propagules of potentially invasive species and developing collaborative initiatives with enterprises that rely largely on alien species (for example, horticulture, agriculture and forestry, including community forestry) to minimize the introduction and use of potentially invasive species. An example of the first type of intervention would be to implement more effective inspection systems at international border and customs posts. This type of intervention can only be effective if those who are directly affected—whether businessmen, tourists or migrants — understand the requirement for these measures, and collaborate. The need to build public awareness of the critical importance of the human dimension of invasions emerges as a key theme from this analysis and is the basis for better-informed decisions, more effective control programmes and a reduction of further invasions.

Link:
http://planet.uwc.ac.za/nisl/Invasives/Assignment1/LeMaitre.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

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Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
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KEANE & CRAWLEY 2002

2006-06-04T20:10:00.000+02:00

Exotic plant invasions and the enemy release hypothesis

To curb the future economic and environmental impacts of invasive exotic species, we need to understand the mechanisms behind exotic invasions. One commonly accepted mechanism for exotic plant invasions is the enemy release hypothesis (ERH), which states that plant species, on introduction to an exotic region, experience a decrease in regulation by herbivores and other natural enemies, resulting in a rapid increase in distribution and abundance. The success of classical biological control has been used as support for ERH, but this observational evidence does not directly test ERH, and the more experimental evidence is equivocal. Competitive release through greater generalist enemy impact on natives seems to be an important but under-studied mechanism of enemy release, but there is a serious need for experiments involving exclusion of natural enemies in invaded plant communities. With a clearer understanding of the role of enemy release in exotic plant invasions, we can begin to build a comprehensive predictive model of exotic plant invasions.

Link:
http://planet.uwc.ac.za/nisl/Invasives/Assignment1/KeaneandCrawley.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

GIRAUD 2002

2006-06-04T20:05:00.000+02:00

Evolution of supercolonies: The Argentine ants of southern Europe

Some ants have an extraordinary social organization, called unicoloniality, whereby individuals mix freely among physically separated nests. This type of social organization is not only a key attribute responsible for the ecological domination of these ants, but also an evolutionary paradox and a potential problem for kin selection theory because relatedness between nest mates is effectively zero. The introduction of the Argentine ant in Europe was apparently accompanied by a dramatic loss of inter-nest aggression and the formation of two immense supercolonies (which effectively are two unicolonial populations). Introduced pulations experienced only limited loss of genetic diversity at neutral markers, indicating that the breakdown of recognition ability is unlikely to be merely due to a genetic bottleneck. Rather, we suggest that a ‘‘genetic cleansing’’ of recognition cues occurred after introduction. Indeed workers of the same supercolony are never aggressive to each other despite the large geographical distance and considerable genetic differentiation between sampling sites. By contrast, aggression is invariably extremely high between the two supercolonies, indicating that they have become fixed for different recognition alleles. The main supercolony, which ranges over 6,000 km from Italy to the Spanish Atlantic coast, effectively forms the largest cooperative unit ever recorded.

Link:
http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Giraud.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

DUKES & MOONEY 1999

2006-06-04T19:58:00.000+02:00

Does global change increase the success of biological invaders?

Biological invasions are gaining attention as a major threat to biodiversity and an important element of global change. Recent research indicates that other components of global change, such as increases in nitrogen deposition and atmospheric CO2 concentration, favor groups of species that share certain physiological or life history traits. New evidence suggests that many invasive species share traits that will allow them to capitalize on the various elements of global change. Increases in the prevalence of some of these biological invaders would alter basic ecosystem properties in ways that feed back to affect many components of global change.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/DukesandMooney.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

BINNS, ILLGNER & NEL 2001

2006-06-04T19:38:00.000+02:00

Water Shortage, Deforestation and Development: South Africa's Working for Water Programme

In the post-apartheid era, South Africa is experiencing a serious water supply crisis as demand increases from both rural areas and rapidly growing towns and cities. New dams and water transfer schemes are being constructed, but they are both controversial and unlikely to fully satisfy demand. Alien species of trees and plants have invaded many plants of the country, taking over land from indigenous species. These alien species consume much more water than indigenous vegetation, as well as threatening biodiversity and constituting a significant fire hazzard. The Working for Water Programme, established in 1995, and working in partnership with local communities, aims to clear invasive alien species and thus increase water supply. The programme is examined in terms of its impacts on environment and the livelihoods of predominantly poor rural communities. Questions are raised about the future sustainability of the programme.

Link: http://planet.uwc.ac.za/nisl/invasives/Assignment1/Binns.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za

Web http://nisl.uwc.ac.za/

D'ANTONIO & MEYERSON 2002

2006-06-04T19:15:00.001+02:00

Exotic Plant Species as Problems and Solutions in Ecological Restoration: A Synthesis

Exotic species have become increasingly significant management problems in parks and reserves and frequently complicate restoration projects. At the same time there may be circumstances in which their removal may have unforeseen negative consequences or their use in restoration is desirable. We review the types of effects exotic species may have that are important during restoration and suggest research that could increase our ability to set realistic management goals. Their control and use may be controversial; therefore we advocate consideration of exotic species in the greater context of community structure and successionand emphasize areas where ecological research could bring insight to management dilemmas surrounding exotic species and restoration. For example, an understanding of the potential transience ofexotics in a site and the role particular exotics might play in changing processes that influence the course of succession is essential to setting removal priorities and realistic management goals. Likewise, a greater understanding of the ecological role of introduced species might help to reduce controversy surrounding their purposeful use in restoration. Here we link generalizations emerging from the invasion ecology literature with practical restoration concerns, including circumstances when it is practical to use exotic species in restoration.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/DAntonioandMeyerson.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za/

COLAUTTI & MacISAAC 2004

2006-06-04T19:04:00.000+02:00

A neutral terminology to define ‘invasive’ species

The use of simple terms to articulate ecological concepts can confuse ideological debates and undermine management efforts. This problem is particularly acute in studies of non-indigenous species, which alternatively have been called ‘exotic’, ‘introduced’, ‘invasive’ and ‘naturalised’, among others. Attempts to redefine commonly used terminology have proven difficult because authors are often partial to particular definitions. In an attempt to form a consensus on invasion terminology,we synthesize an invasional framework based on current models that break the invasion process into a series of consecutive, obligatory stages. Unlike previous efforts, we propose a neutral terminology based on this framework. This ‘stagebased’ terminology can be used to supplement terms with ambiguous meanings (e.g. invasive, introduced, naturalized, weedy, etc.), and thereby improve clarity of future studies. This approach is based on the concept of ‘propagule pressure’ and has the additional benefit of identifying factors affecting the success of species at each stage. Under this framework, invasions can be more objectively understood as biogeographical, rather than taxonomic, phenomena; and author preferences in the use of existing terminology can be addressed. An example of this recommended protocol might be: ‘We examined distribution data to contrast the characteristics of invasive species (stages IVa and V) and non-invasive species (stages III and IVb)’.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/ColauttiandMacIsaac.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za/

BERTOLINO & GEN0VESI 2002

2006-06-04T18:53:00.000+02:00

Spread and attempted eradication of the grey squirrel (Sciurus carolinensis) in Italy, and consequences for the red squirrel (Sciurus vulgaris) in Eurasia.

In 1997, the National Wildlife Institute, in co-operation with the University of Turin, produced an action plan to eradicate theAmerican grey squirrel from Italy, as this introduced species replaces the native red squirrel through competitive exclusion anddamages trees through de-barking. The ﬁrst step, a trial eradication of a small population of grey squirrels at Racconigi (Turin) toevaluate the efficiency of the removal techniques, started in May 1997. Preliminary results showed that eradication was feasible, butthe project was opposed by radical animal rights groups which took the National Wildlife Institute to court in June 1997. This legalaction caused a suspension of the project and led to a lengthy judicial enquiry that ended in July 2000 with the acquittal of theInstitute. Nevertheless, the 3-year suspension of all actions led to a signiﬁcant expansion of the grey squirrel’s range and thus eradicationis no longer considered practical. Therefore, in the medium to long term, grey squirrels are likely to expand through continentalEurasia. This constitutes a major threat to the survival of the red squirrel over a large portion of its distribution range andwill have a signiﬁcant impact on forests, with economic damage to timber crops.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/BertolinoandGenovesi.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

BENNING 2002

2006-06-04T18:51:00.000+02:00

Interactions of climate change with biological invasions and land use in the Hawaiian Islands: Modeling the fate of endemic birds using a geographic information system

The Hawaiian honeycreepers (Drepanidae) represent a superbillustration of evolutionary radiation, with a single colonizationevent giving rise to 19 extant and at least 10 extinct species[Curnutt, J. & Pimm, S. (2001) Stud. Avian Biol. 22, 15–30]. They alsorepresent a dramatic example of anthropogenic extinction. Cropand pasture land has replaced their forest habitat, and humanintroductions of predators and diseases, particularly of mosquitoesand avian malaria, has eliminated them from the remaining lowandmid-elevation forests. Landscape analyses of three highelevationforest refuges show that anthropogenic climate changeis likely to combine with past land-use changes and biologicalinvasions to drive several of the remaining species to extinction,especially on the islands of Kauai and Hawaii.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Benning.pdf

Difficulty C

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za/

ALPERT, BONE & HOLZAPFEL 2000

2006-06-04T18:26:00.000+02:00

Invasiveness, invasibility and the role of environmental stress in the spread of non-native plants

Invasion ecology, the study of how organisms spread in habitats to which they are not native, asks both about the invasiveness of species and the invasibility of habitats: Which species are most likely to become invasive? Which habitats are most susceptible to invasion? To set the stage for considering these questions with regard to plants, we offer a two-way classification of nativeness and invasiveness that distinguishes natives, non-invasive non-natives and invasive non-natives. We then consider the current state of knowledge about invasiveness and invasibility. Despite much investigation, it has proven difficult to identify traits that consistently predict invasiveness. This may be largely because different traits favour invasiveness in different habitats. It has proven easier to identify types of habitats that are relatively invasible, such as islands and riverbanks. Factors thought to render habitats invasible include low intensities of competition, altered disturbance regimes and low levels of environmental stress, especially high resource availability. These factors probably often interact; the combination of altered disturbance with high resource availability may particularly promote invasibility. When biotic factors control invasibility, non-natives that are unlike native species may prove more invasive; the converse may also be true. We end with a simple conceptual model for cases in which high levels of environmental stress should and should not reduce invasibility. In some cases, it may be possible to manipulate stress to control biological invasions by plants.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/Alpert.pdf

Difficulty A

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za/

ALLDORF & LUNDQUIST 2003:

2006-06-04T18:22:00.000+02:00

Introduction: Population Biology, Evolution, and Control of Invasive Species

Invasion by nonindigenous species has been recognized as second only to loss of habitat and landscape fragmentation as a threat to global biodiversity (Walker & Steffen 1997 ). The economic impact of these species is a major concern throughout the world. For example, an estimated 50,000 nonindigenous species established in the United States cause major environmental damage and economic losses that total over an estimated U.S.$125 billion per year (Pimentel et al. 2000). Management and control of nonindigenous species is perhaps the biggest challenge that conservation biologists will face in the next few decades.

Link: http://planet.uwc.ac.za/nisl/Invasives/Assignment1/AllendorfandLundquist.pdf

Difficulty B

Dr Richard Knight Co-ordinator: National Information Society Learnerships - Ecological Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za
Web http://nisl.uwc.ac.za

ASSIGNMENT 1 (20%): REVIEWING A SCIENTIFIC PAPER

2006-06-04T12:37:00.000+02:00

Hi Everyone

I will put up the abstracts of some 20 research papers, which you will review, and from your review you will prepare a Narrated Presentation. These Paper Reviews will be put up for all people to comment on. Our UWC students have completed theirs (David all parts) and Karen (just needing to add her narration - the original microphone supplied was poor quality).

A Review is NOT...

just a summary of the paper.
examination ONLY of the material contained in the paper.
only a re-statement of the points made by the authors.

A Review IS...

a critical but fair analysis of the quality of the research paper.
putting the research into perspective of other research that has been undertaken.
an expression (at least in part) of your own opinions and suggestions, including where improvements could be made.

In essence your review should been seen as a constructive critique and at least some reflections of your own points of view.

I will put up abstracts and links for each paper as individual postings and you will book by adding a comment confirming acceptance of this paper for your review.

Instruction Points

Use the latest template (since the CSIR logo has changed) and this can be downloaded from the following URL (Right Mouse Click and Save Target as)

http://planet.uwc.ac.za/nisl/NISL_templates/NISL_Template_EI_2.ppt

For each slide you will need an audio file using either your Windows Sound Recorder which limits sopund clips to 60 seconds or to download the free software Audacity

http://audacity.sourceforge.net/ (Sorry I cannot help you on learning how to use this!)

I have provided a mini-video showing you how to use your Windows Sound Recorder to make audio files. Audio files need to be name slide1, slide2 etc and when completed please use WinZip to zip the files to make a single compressed file for emailing to me. (if you do not know how to make a Zip File please let me know by adding a comment to this posting)

http://planet.uwc.ac.za/nisl/NISL_templates/Audio/recorder.html

The Ruderic for marking this assignment can be found at the following URL (Right Mouse click and Save Target as)

http://planet.uwc.ac.za/nisl/Invasives/Assignment1/

Please note that if you take a more difficult and longer paper may get awarded bonus marks (additional 10 marks), wheras very easy or short paper you will only get marked out of 90. Difficult or longer papers are indicated with an A, whereas the easiest papers are indicated with a C. Most of the papers are graded with a B and therefore are marked out of 100.

Final Deadline is 15 June 2006 and the PowerPoint should be emailed to mailto:toknight.rich@gmail.com (with the heading "Invasives_assignment_1") and the Document name: Initial_Surname_invasives_2006_assignment_1.ppt and Initial_Surname_invasives_2006_assignment_1.zip as the attached file names (failure to correctly name your files will or provide the incorrect heading for your email message will incur a 10% penalty). If your font page of your Power Point does not carry full contact details you will also be subject to a further 10% penalty.

upload via ftp to the following directory (please ask by email for login details)
http://planet.uwc.ac.za/nisl/invasives/Assignments_collect/2006

Cheers

Rich

COURSE OUTLINE

2006-06-03T14:35:00.000+02:00

This course covers Invasion Biology a the the most holistic level, and examines the problems, as well as provide mechanisms of analysis that potentially identify risks that an introduced species pose plus the ability to predict which environments it wil be mostinvasive.

Objectives

Examine the economic implications in terms of direct impact on Gross National Productivity.
Examine how Invasion Species threaten Biodiversity.
Examine how Invasies Species impact many industries such as agriculture and aquaculture/mariculture and threatens food security.
Examine how Invasion Biology is an International Issue and requires integrated and unified actions, that are political as well as managerial.

Outcomes

Use of an Expert System to determine the risk association with an introduction of a new species into a host environment.
Using of species prediction methods to identify how much environment is at risk from invasion.
Analysis of the Global Invasive Alien Species (GISP) Information Portal

Resources Required

Access to a GIS, either IDRISI or ArcView.

Mark allocation

Paper Review (Narrated Power Point) 20%
Expert System 30%
GARP Species Prediction 30%
Analysis of the GISP Information Portal providing the basis for substantial contribution(s) to the Weblog or Formal Testing (exams) 20%

Resources

Assignment 1 - The Ruderic for assessment of this is here. Individual Abstracts for each Paper will be put up on the Blog and you will book by adding a comment.

Assignment 2 - This assignment is based on the research paper by Tucker and Richardson which can be found here. The full instructions can be found here. Click here to access an Expert system used to screen Invasive Species of the Cape Region here

Here is the direct link to the excel sheet from which you must select your species and to give you pointers to the right answers which you need to find data sources and reference them.

http://planet.botany.uwc.ac.za/nisl/invasives/Assignments/Expert_system/expert.xls

Assignment 3 - Presentation of Invasive Species (their distributions) is presented here. A description of the technique for using GARP is presented here.

I hope you enjoy this course.

Cheers

Rich

PLAGIARISM DECLARATION

2006-05-29T19:45:00.000+02:00

Hi Folks

At a recent BCB departmental meeting (May 2006) it was agreed that all
students will need to sign an undertaking that their assignments have
not been plagiarised and are correctly referenced. At an earlier meeting
in 2006 the department agreed to using the CSE/CBE style for all
referencing in student assignments. It was also recommended that all
electronic courses also carry such a declaration. To this end you will
note that a plagiarism declaration has been added to the right hand side
of the Weblog ensuring compliance and understanding of the issues of
plagiarism and correct citation, quotation and referencing.

It is important that you understand these issues and to this end Gwen
and Nick have put a lot of effort in helping your identify and not to
commit plagiarism while undertaking the Biodiversity course. I trust
that this message is now fairly comprehensively understood, nevertheless
you may submit certain assignments to Nick who has agreed to check them
as per the revised schedule put up by Gwen in an earlier posting on the
Biodiversity Blog (See
http://bcb705.blogspot.com/2006/05/correction-editing-times.html )

How to avoid plagiarism?
Make your own notes when revising material and keep a record of all the
references you have consulted.Organise your notes into a mind map of the
assignment.Use your notes and mind map to prepared the final
assignment.Get a classmate to look through your assignment before
submitting, for both plagiarism and proper referencing.For submitting on
the Weblog and when preparing Power Point presentations, I would
recommend using a number in brackets after the text. The number should
be hyperlinked to the article if it is available electronically
available. The numbers must be organized in ascending order and placed
within square brackets [1].Do a few checks of phrases of five words or
more using a Google SearchFinally quickly read through your more
important references to check that you subconsciously have not slipped
in a near verbatim phrase.

Some important references to Plagiarism on the NISL Weblogs that you
have participated in

PLAGIARISM: OFFICIAL RULING AND DEFINITION - SENATE UWC

http://bcb703.blogspot.com/2006/04/plagiarism-official-ruling-and.html

DEFINING PLAGIARISM

http://bcb703.blogspot.com/2006/03/defining-plagiarism.html

STANDARDISED PENALTIES FOR THE SCIENCE FACULTY

http://bcb703.blogspot.com/2006/03/standardised-penalties-for-science.html

THE HUNT IS ON FOR PLAGIARISM

http://bcb705.blogspot.com/2006/05/hunt-is-on-for-plagiarism.html

BIODIVERSITY TAUGHT THROUGH THE WEBLOG

http://bcb705.blogspot.com/2006/04/biodiversity-taught-through-weblog.html

EXTENSIONS, TESTS AND PLAGIARISM

http://bcb705.blogspot.com/2006/05/extensions-tests-and-plagiarism.html

Plagiarism and Referencing: Hopefully the last word

http://bcb705.blogspot.com/2006/05/plagiarism-and-referencing-hopefully.html

Cheers

Rich, Gwen and Nick

Dr Richard Knight
Co-ordinator: National Information Society Learnerships - Ecological
Informatics
Department of Biodiversity and Conservation Biology
University of the Western Cape
Private Bag X17
Bellville 7535

Phone 27 + 21 + 959 3940
Fax 27 + 21 + 959 1237

Email Rknight@uwc.ac.za

Web http://nisl.uwc.ac.za