Walleye aren't bad fish, just the wrong fish for Idaho - Idaho Fish and Game

Fish and Game has an ongoing project in Lake Pend Oreille in North Idaho to keep established walleye populations from growing and consuming kokanee that provide a popular fishing opportunity, as well as feeding trophy trout populations in Idaho's largest lake. 

Not a bad fish, just the wrong fish for Idaho

Some anglers have accused Fish and Game biologists of being biased against walleye, which isn't true. Biologists have spent decades surveying anglers for their preferences, and biologists have done their best to provide diverse fishing opportunities that are geared toward angler preferences, which includes walleye fishing. 

However, in most Idaho waters, biologists aren't managing a single species, they're managing multiple species that must be somewhat compatible with each other. Any given water can only support so many fish, and while it's common for game fish to feed on each other, there's an opportunity to maintain a reasonable balance between species. 

Biologists take all those factors into consideration before introducing a fish species into any water. Unfortunately, in the case of Lake Lowell, someone decided to illegally release walleye that are showing signs of successfully reproducing. 

"When a highly predatory species is introduced to a water outside that established process, as walleye were in Lake Lowell, we are forced to dedicate a lot of resources towards assessing the impact on the existing fishery, and unfortunately, most of our anglers are robbed of the opportunity to weigh in on the matter," Fish and Game's Southwest Region Fisheries Manager Art Butts said. 

Walleye are a valued fish with a checkered history

Walleye are among the favorite fish species in the some parts of the country, particularly the upper Midwest and Great Lakes area where the fish flourish and anglers love to catch and eat them. 

But numerous cases in the Northwest and Rocky Mountain states have shown a fairly predictable trend after walleye populations are established in waters that didn't previously have them. At best, the available fish species shift and another fishing opportunity is added. But more often, a limited walleye fishing opportunity displaces established and valued fish populations of other species. 

Case in point is Canyon Ferry Reservoir in west-central Montana. The reservoir had a thriving perch population, as well as a healthy trout population. In the 1990s, anglers started catching walleye, which were previously unknown in the reservoir. 

Walleye populations quickly grew and by 2000, their average size had grown to the point they were effective predators of perch and trout. By 2004, nearly all the perch were gone, and trout populations had also plummeted. Montana shored up the trout population by planting catchable fish rather than fingerlings, but overall, trout angling efforts were roughly halved. 

Anglers turned to walleye, which offset some of the loss of angling effort, but perch populations never recovered, and interest in trout fishing declined. Walleye fishing continues at Canyon Ferry Reservoir, but largely for small to medium-sized fish because they've consumed most of the available forage. 

Moses Lake in Washington is another case where walleye have dramatically changed a fishery. In the early 1980s, the lake's crappie population crashed, and when Washington Department of Fish and Wildlife biologists surveyed the lake, they discovered a walleye population. 

According to WDFW fisheries biologists Marc Peterson, the walleye population there "expanded before we knew what was going on." 

In the decades since, he's seen walleye shift the lake's entire fish population from crappie, bluegill and largemouth bass to mostly walleye and smallmouth bass as the predominate species. He added that other fish species still exist, and their populations can fluctuate from year to year, but "you can change the complexion of a lake's entire fish composition with walleye."