Background: Yellowstone cutthroat are in serious decline in Yellowstone Lake largely thanks to predation from an exploding population of invasive, non-native lake trout. Numbers of cutthroat in the Yellowstone Lake ecosystem have dropped to less than five percent of the historic population. 25 years ago, spawning returns in the Clear Creek tributary were 50,000 fish per year. Current returns in the same tributary are less than 500 fish.
The National Park Service’s 1994 study reported an anticipated economic loss of $36 million in revenue per year with a 50 percent YCT population decline within the Yellowstone Lake system. Based on current population surveys more than 95 percent of the YCT population has since been lost.
The population of Yellowstone cutthroats inhabiting Yellowstone Lake system is one of the only remaining genetically pure populations found in the native range of this subspecies, which includes parts of Wyoming, Montana and Idaho. Yellowstone cutthroats are a keystone species of the park’s ecosystem . More than 40 species, including include eagles, grizzly bears, ospreys and river otters depend on the fish as a food source.
Update: Yellowstone National Park has recently released its Native Fish Conservation Plan Environmental Assessment (NFCPEA) detailing plans for restoring the park’s native coldwater fisheries during the next 20 years. The public comment period on the plan and environmental assessment runs through Jan. 31.
Trout Unlimited strongly supports the plan’s proposal to make lake trout suppression the highest priority of the park’s native fish management program. TU agrees this means significantly increasing netting and trapping of the invasive fish, while identifying – as the plan does – measurable objectives for lake trout mortality as well as a corresponding rebound in the cutthroat population.
TU is urging the park to reinforce its plan by adopting and implementing the recommendations of the 2008 Scientific Review Panel that the Park Service convened to evaluate lake suppression and other efforts aimed at restoring the lake population of cutthroats.
Among the recommendations the panel made to the park are:
1.) Identify the size and demographic details of the lake trout population.
2.) Study the movement of lake trout so that removal efforts can be better targeted
3.) Institute a rigorous monitoring plan that can provide reliable information on the effectiveness of netting and trapping, as well as the response of the cutthroat population
4.) Create a scientific committee of non-park personnel to review Park activities
5.) Support development of alternative suppression technologies (such as those that can interfere with lake trout reproduction and recruitment).
The plan and EA also identify measurable targets and potential projects for restoring Yellowstone cutthroat populations in streams outside the lake system, as well as measures and objectives for significantly improving populations of the park’s other native salmonids, westslope cutthroats and fluvial arctic grayling. Trout Unlimited supports these as important secondary objectives.
DO IT: To comment on the Yellowstone National Park Native Fish Conservation Plan Environmental Assessment before Jan. 31, here’s the link to both the plan and the entry point for comment:
Or write to: Native Fish Conservation Plan, Yellowstone National Park, P.O. Box 168, Yellowstone National Park, WY 82190.