Headed by an ecologist at the University of Alberta, the study found a direct connection between the rapid growth of fish farming in the waters off British Columbia and an abrupt decline in the number of wild salmon, The Washington Post (NYSE:WPO) reported Friday.

"These young salmon wouldn't be dying if it wasn't for the salmon farms and those sea lice," said Martin Krkosek, the lead author of the study published by the journal Science.

Sea lice are naturally occurring parasites that attach themselves to wild salmon in the open ocean and feed on their skin and muscle tissue, the Post report said. They thrive in open-net salmon farms because the fish are crowded together.

Adult salmon living far offshore can cope with the lice but not wild juveniles heading out to sea.

Besides Canada, fish farming is widespread along the coast of Maine, northern Europe and Chile.

Legislation involving a major expansion of fish farming is currently before the U.S. Congress, the Post said.