How Aquaculture Is Threatening the Native Fish Species of Africa
In 1995, Adrian Piers, a veteran aquaculture consultant, imported a batch of Australian red claw crayfish to the tiny southern African monarchy of Swaziland. He began raising the attractive blue-green crustaceans — the males of which have red stripes on their claws and can weigh a little more than a pound — in ponds rented from a sugar estate, and soon found a market for them among French-style chefs in neighboring South Africa.
In 2001, citing lower-than-desired profits, he closed his operation in Swaziland and legally moved some crayfish almost 750 miles north to his home country of Zambia. Piers kept them temporarily at Kafue Fisheries, a friend’s commercial farm, while searching for a permanent place to breed them. “Unfortunately he was a bit new to the crayfish, and they managed to get out,” Piers explains. The crayfish were soon found thriving in the nearby Kafue River, one of Zambia’s largest, and in waterways near his old Swazi farm, too, even though he had dried out his ponds before he left. Someone (Piers won’t say who) then unofficially put some in Lake Kariba, the giant man-made lake between Zambia and Zimbabwe, where they are now proliferating.
photo credit: hans pohl