The populations of native and invasive pike in Alaska make for interesting fishing regulations and rules in the last frontier. A recent article by the Alaska Department of Fish & Game shares the differences between invasive and native pike. Read below to learn about the impacts invasive pike have on other fish populations and to understand the possible cause of what happened to allow invasive pike to appear in south-central Alaska.
Where Are Pike Native in Alaska?
Northern pike are naturally in waters north and west of the Alaska Range. They are thought to have been in these areas since the ice age. Alaskan northern pike are also genetically related to Siberian pike. It is believed pike amongst other species moved from Siberia and Alaska using rivers on Beringia. For 10,000 years pike naturally resided in the Northern and western parts of Alaska. This all changed about seventy years ago…
Invasive Pike: How & Where
Northern Pike started to be found south of the Alaska Range in southcentral Alaska during the late 1950s. Nobody knows precisely how they got there but local Alaskans think that a bush pilot transferred pike from Minto Flats (located near Fairbanks) to Bulchitna Lake in southcentral Alaska. The pilot likely thought he would have a nice remote and fairly private pike-filled lake for some awesome fishing, but he probably did not think about what would happen if the lake flooded. Flooding did happen and the pike got into the Yentna River, which is connected to a variety of waters in southcentral Alaska. Unfortunately, pike have been illegally spread to other places, and they are now found in over 150 waters.
Impacts of Invasive Pike
Pike are very aggressive and will eat just about anything they encounter. Water systems that once had salmon or trout become destroyed when pike take over. Northern pike thrive in shallow, stagnant/slow-moving waters with vegetation. Pike are native to waters up north that are home to other fish species. They have shaped those communities for so long that both pike and the other fish can live together without huge ecological impacts. In the Susitna drainage of southcentral Alaska, waters that are slow and shallow are where salmon and trout naturally live. Pike come in and reshape these fish communities, and it often happens too fast for native species to adapt, which can devastate populations of native fish.
An unfortunate example of pike taking over was in Anderson Lake. Located in Wasilla, Alaska, this lake was recently part of a pike eradication project and the whole lake was poisoned with rotenone to kill the invasive pike and protect nearby waters. After the lake was poisoned, 12,000 pike were removed. They were all found to be stunted, there were none over 24 inches. This occurs when pike destroy other fish populations and run out of large food sources. The only other fish found in Anderson Lake were five longnose suckers. The pike truly decimated the lake. ADF&G said that was one of the worst cases they had seen in over 12 years of eradication projects.
In southcentral Alaska, it is illegal to release northern pike and they can even be taken by spear or bow and arrow. In northern and western Alaska the laws are quite different for native pike and it is recommended to look at local regulations.
To learn more about native and invasive pike in Alaska check out the original article, “Native vs. Invasive Pike A Tale of Two Ranges” by Alaska Department of Fish and Game biologist Kristine Dunker.