GLAND, Switzerland — Monstrous cannibal fish in Lake Victoria have turned a dream of food into an ecological disaster for surrounding East African countries, environmental scientists report.
Officially named the Nile perch but called "elephant of the water" by Lake Victoria fishermen, the enormous creature grows to the size of a man and weighs up to 220 pounds. The species of carp-like fish was introduced into the lake in 1960 in hopes of providing a new source of high-yield protein.
But scientists warned too late about possible danger to other species. Now, 25 years later, the nightmare has come true, the International Union for the Conservation of Nature reported recently.
The agency, which shares headquarters with the World Wildlife Fund, said the "elephant of the water" has practically cleared the lake--bordered by Kenya, Tanzania and Uganda--of about 300 species of fish and crustaceans.
"Now the carp are cannibalizing their own kind because there is nothing left for them to devour," agency spokesman Drake McHugh said. "There is no reason to believe this trend will ease before most of Lake Victoria's native fish species, many of which are unique to this one water, have been wiped out."
Most local Africans will not even eat the monster fish because it is so oily that it requires heavy smoking.
Sun-drying is inadequate as a fat-reducing process, and fishing nets are also broken by the sheer weight of the fish.
Dozens of the species devoured by the monster perch were ornamental fish that were a valuable source of income to local fishermen. At least one species helped control the human killer disease schistosomiasis by preying on the water snail that carries the virus.
"Nevertheless, and incredibly, plans are afoot to repeat the experiment very soon in Lake Malawi and other large lakes in the region," the nature agency said.