African Wildlife & Environment Issue 84 2023

F W F N EW ESSLSEAT TLE RA D5 E(R2S0H2 I3P)

SAVING SANDFISH IN THE CEDERBERG

most of its former range due to predation by alien fish and habitat degradation; now less than 200 migrate up the Biedouw River to spawn. ‘Sandfish Sanctuaries’ are farm dams in the area that have been cleaned of non-native fish like Bass and Bluegill to create safe environments for the young sandfish to live. After a year or two the fish have grown from five to twenty centimetres – rendering them now ‘bass-proof’ and they can then be released back into the wild to boost the dwindling sandfish spawning population in the Biedouw River. To date over 1,500 bass-proof sandfish have been released from the sanctuary dams back to the Biedouw River where they were born. Scientists from the Freshwater Research Centre are using tiny, harmless tags implanted into each fish to track the survival and migrations of these sanctuary-reared fish, and the results thus far look promising. The sandfish rescue-rear-release approach has boosted the adult spawning population in the Biedouw River by 55% - a big step towards preventing sandfish extinction – and this is just the beginning, with plans to ramp up these efforts now that there is proof of concept. The next phase of the project is now working to restore 7 km of the upper Biedouw River by removing invasive species to reclaim critical habitat for the Endangered Sandfish and five other indigenous fish species. The Saving Sandfish project is a collaborative South African freshwater conservation effort, supported by the Ford Wildlife Foundation, National Geographic Society, IUCN Save Our Species, the Mohamed Bin Zayed Species Conservation Fund and others. Project partners include the Freshwater Research Centre, the Fynbos Fish Trust, Mount Ceder, Bushman’s Kloof and CapeNature. Find out more about the Saving Sandfish project and how to get involved here .

Text and images by Dr Jeremy Shelton

The Biedouw River is one of the last known spawning tributaries of the Endangered Clanwilliam Sandfish – South Africa’s most threatened migratory freshwater fish. It was once widespread in the Olifants and Doring River systems, with tens of thousands of fish undertaking impressive migrations to their spawning sites in springtime. The species has disappeared from

Transporting fingerlings to the Sandfish sanctuaries

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