FAIRBANKS - Genetically modified fish from farms eventually could present "considerable" environmental risks, according to a federal science panel.
The National Research Council devoted several pages to fish in a report on biotechnology it released last week. The U.S. Food and Drug Administration requested the report in response to controversy over genetically modified foods.
The research council ranked fish second-highest, behind insects, in a listing of animal types that would raise concern if given new genes.
Farmed fish that escape can disperse rapidly and widely. Once in the wild, the fish could compete against or disrupt natural fish populations, the report said.
"The committee's review of ecologic principles and empirical data suggests a considerable risk of ecologic hazards" if genetically modified fish enter natural ecosystems, the report concluded.
Tom Gemmell, executive director of United Fishermen of Alaska in Juneau, said the report strengthens the case against fish farms, which his organization opposed.
State law bars fish farms in Alaska waters, but dozens of farms raise Atlantic salmon in British Columbia, mostly around Vancouver Island. The B.C. government recently lifted a moratorium on new salmon farms.
No genetically modified fish are being farmed at this point, according to the Canadian Aquaculture Industry Alliance, which opposes the use of such fish.
But the National Research Council report said the industry could turn toward the new stocks later.
"Considerable research effort has been devoted to development of genetically enhanced fish and shellfish stocks, as they pose considerable benefits to producers," the report said.
The review offered with no specific predictions about what might happen if genetically modified fish escaped. Some farmed fish have escaped from B.C. farms, for example.
"It is difficult to assess the likely ecologic or genetic outcome should transgenic Atlantic salmon escape captivity and invade wild populations," the report said.
Studies have shown that, in the salmon family, larger fish have an advantage in spawning. But other studies indicate large genetically modified fish are less likely to produce healthy young.
The two discoveries together present a danger, the panel said. If a modified gene improves spawning success but hurts juvenile viability, "the result is a gradual spiraling down of population size until eventually both wild-type and transgenic genotypes become locally extinct," the report said.
All this is still theory, the panel notes. The information available to date "does not yet provide a body of data useful" for modeling what might happen.
Atlantic salmon, which account for 80 percent of B.C. farmed salmon production, are a different species from the Pacific varieties and aren't likely to interbreed. But they have been caught in Southeast Alaska and as far west as the Bering Sea. Spawning has been documented in some Vancouver Island streams.