Amid ongoing lake trout reduction efforts, the fish continues to dominate Yellowstone waters, according to park officials.
Although there have been reported successes with the program—last November, we reported that crews removed nearly 366,000 lake trout form Yellowstone Lake—it’s all but impossible to extirpate them.
According to KPAX Missoula, managers have a variety of tools available in driving down lake trout numbers but can’t eliminate them entirely:
“As managers there’s really no way that we can totally eradicate that invasive species,” explained YNP Native Fish Conservation Program leader Todd Koel. “They are pretty much here to stay, all we can do is manage the best that we can their numbers in our case for lake trout to suppress them using an aggressive gill netting program and by suppressing the lake trout we’re allowing the cutthroat trout then to rebound and become an ecologically important component of that system again.
The efforts to suppress the lake trout in Yellowstone Lake are being hampered by the weather. Suppression efforts can only happen about six months out of the year since the lake is frozen for the rest of the year — something that gives the lake trout an advantage.
Lake trout were first introduced to Yellowstone in the 1980s. They displaced the smaller native cutthroat trout, an essential species for birds of prey and grizzly bears. Anglers and park enthusiasts also prize the cutthroat trout.
In addition to preying on cutthroat trout, lake trout also empty out the cutthroat’s ecological niche, since they don’t frequent shallow water often. In other words, they aren’t a reliable food source for eagles, ospreys, bears and the like.