Invasive pike thriving on salmon, other species

Northern pike occur naturally in most of Alaska, but they are not native to Southcentral. In the areas where pike do not naturally occur (yellow), they are an invasive fish species and are capable of causing a lot of damage. (Map courtesy of Alaska Fish and Game)

A federal and state study says northern pike that gobble up salmon fingerlings in Alaska streams can thrive long after that valuable species has been decimated.

The study concludes that nonnative pike prefer juvenile salmon but will turn to other native fish when salmon are less abundant.

The authors say invasive pike can continue to thrive as they drive multiple Alaska species to low abundance.

Researchers from the U.S. Geological Survey and the Alaska Department of Fish and Game conducted the study in the Deshka River and Alexander Creek. Both feed into the Susitna River.

The Deshka has multiple salmon populations and enough salmon returning from the ocean each year to sustain a fishery. Researchers picked Alexander Creek because of the downward trend in king salmon abundance there.