Fish & Water - Sounds Wild
Invasive Pike

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Invasive Pike

An angler in a canoe fishing a creek on the Kenai Peninsula has just caught a small northern pike. He kills it - not because he plans to eat it, but because pike are an introduced and unwanted fish in this part of the state. Alaskans are working to eradicate these invasive pike on the Kenai.

Pike in their native range coexist with salmon and trout in many of the big Interior Alaska river drainages. So what is the problem with pike on the Kenai? Pike are ambush predators, darting from weed beds to catch unsuspecting prey. In habitat without weedy, slow-moving water, pike are less efficient predators. Deep or fast-flowing water serves as a refuge for prey.

Southcentral Alaska has a lot of shallow vegetated lakes and streams that for thousands of years have served as nurseries for juvenile trout and salmon - fish that evolved without a large, top of the food chain predator like pike. On the Kenai, invasive northern pike have completely eliminated native rainbow trout, Dolly Varden, and juvenile coho salmon from many lakes in the Soldotna Creek drainage. Pike wiped out Arctic char and rainbow trout in Stormy Lake near Nikiski. Smaller pike feed heavily on juvenile salmon and trout when available, and when that runs out, shift to stickleback, sculpins, frogs and mice - and even cannibalize each other. Once the richest resources are depleted, pike growth stunts, and lots of small and hungry pike are the rule.