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South Africa |
ECOLOGY
Environmental and ecological problems are increasingly concerning many African countries and individuals
It has sad, bulging, eyes. Its mouth is beefy and protruding rendering the atmosphere around this ashen grey fish funereal. And for good reason. The Eastern Cape Rocky (sandelia bainsii), a unique African freshwater fish species, closely related to the climbing perch of Africa and Asia, is threatened with extinction. An invasion of its main habitats by the South American red water fern and other alien fish and plant species, the constructions of dams, climatic changes and pollution have all contributed to this.
Now a lone South African fish biologist has taken it upon himself to save it from extinction. Dr Jim Cambray, Curator at Albany Museum’s department of Ichthyology in Grahamstown, South Africa, says he was stunned when after a 20-year absence, he came back to South Africa find the fish almost extinct.
To save it, (the World Conservation Union’s red data book has already ranked it as «Critically Endangered», which is the last step before extinction), Cambray is spearheading the Save The Sandelia Bainsii Campaign, a world-wide crusade. The Albany Museum’s researcher is also using this particular case to highlight what is happening to the world’s freshwater ecosystem.
The campaign emphasises the fish’s unique mating behaviour, citing this as reasons for its conservation. It has an unusual mating ritual, whereby the male blows bubbles to lure the female. Dr Cambray has also observed its unique spawning behaviour and has made a video of this. The fish clears a nest area before inviting the female to his breeding area. After a number of chases, the pair embrace and eggs are released. The pair will mate a number of times after which, the male chases away the female and anything else when he guards his eggs.
South African researcher, Dr Monde Mayekiso, who studies the ecology of the Eastern Cape Rocky in the Tyume River, established that the fish breeds between October and February. Unlike most other pisces, the Eastern Cape Rocky prefer quiet rocky habitats where they wedge themselves between rocks or submerged logs and wait for prey items to float or swim past.
The fish (it belongs to the Anabantidae fish family), feeds on invertebrates, crabs, and small fish, and has a greatly elongated swim bladder extending from the caudal peduncle to the head. It grows to 325mm but unlike its African and Asian relatives, the East Cape Rocky’s accessory breathing organs are labyrinthine but greatly reduced in size.
A standard Eastern Cape Rocky can have up to 7,000 eggs. The eggs are round and have a clear oil globule in the middle of the yolk. At the time they are hatched, young East Cape Rockies are only about 3mm long.
The fish derives its genus names —sandelia bainsii — from Chief Sandile (c1820-1878), the son of a famous 19th Xhosa paramount chief, and Andrew Geddes Bain (11797-1864), a road builder, explorer, trader, soldier, writer and the man widely regarded as the father of geology in South Africa.
Its common name, Eastern Cape Rocky, comes from the fact that it is only found in the Eastern Cape province and usually lives in rocky stretches of rivers. Today, it is only found in short sections of six river systems in the area: Kowie, Koonap, the Kat tributaries of the Great Fish river, Keiskamma and Nahoon.
Other members of the anabantidae group are found further north in Africa. The climbing perch (ctenopoma) species is found in East Africa, while the anabas testudineus occurs in Asia.
Success story
Sponsors of the «Save the Sandelia Bainsii Campaign» include the Worldwide Fund for Nature, Ubuntu Welfare and Development Trust, and Flora and Fauna International. Nature Conservation is stocking dams with both the fish and mullet — a small fish species that used to migrate up the Eastern Cape rivers before weirs were built along them. A number of individuals also support the programme.
The campaign involves conservation education programmes, captive breeding of the Eastern Cape Rocky in the upper catchment area where small fish are nurtured in three reserves, and rigorous research on the early life history of this species and its habitat. To help sensitise the local people on the need to involve themselves in the project, the co-ordinators are involving school, farmers and conservation groups. They are also holding on-site talk and have launched a presidential certificate award. The fish is on display at Albany Museum’s Blue Planet gallery.
«It’s been one of our biological control success stories,» says Dr Cambray who describes himself as the «champion» of the rather unspectacular-looking fish.
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