Effect of Alaska flooding on salmon uncertain

ANCHORAGE, Alaska – A scientist with the Alaska Department of Fish and Game says the impact of recent flooding and high waters on Alaska’s salmon won’t be clear for years.

Bob Clark, the department’s chief scientist for sport fish, said there’s a potential for fewer fish in the future, but it’s too early to tell.

“The way we sort of evaluate some of these environmental effects – freezing, flooding, not enough snow, too much snow – at least for salmon is when they come back as adults,” he said.

Fish production could dip if fast-moving water scours spawning sites of eggs, Clark said. Fewer juvenile salmon may survive if those that wind up in flood plains don’t find their way back into rivers once flooding subsides.

Clark said everyone must wait until the salmon come back as adults to get more information.

For pinks, that means two years from now. It’ll be three to four years to know about silvers and reds and four to seven years for kings.

In the mid-1980s, flooding of the Susitna River altered salmon production for a couple of years, but it also moved some pike around, and the dispersal of pike into that drainage has caused problems.

Other species, like trout and Dolly Varden, could lose an important source of food if dead salmon are washed out of rivers.

“It takes food away from the fish,” Clark said, “but it also creates more food, because you get more insects and there’s more movement of leaves into the system.”

Clark emphasized that salmon are adaptable. Those that populate rivers prone to flooding are particularly adaptable, he said.