The drop in numbers may prompt officials to limit fishing in California, Oregon and Washington. In Alaska, where a 90 percent of the king salmon are caught, the harvest could be cut to two-thirds of last year's record catch, the Seattle Post-Intelligencer reported.

The Pacific Fishery Management Council is to meet in SeaTac, Wash., this week to set limits, which it will pass on to the National Marine Fisheries Service.

The fisheries service limits will be announced by May 1, the report said.

The cause of the salmon population collapse is unknown. But demand for salmon is easier to quantify.

"America has become a nation of salmon eaters," said Laura Fleming of the Alaska Seafood Marketing Institute.

Prices for salmon vary by species.

Chum salmon has risen from $1 to $3 a pound, the report said, but king salmon has been at some markets at more than $30 a pound.