Rare Glacier Park insects put on Endangered Species List

Two stoneflies that call Glacier National Park and other mountainous streams home have been added to the Endangered Species List, the U.S. Fish and Wildlife Service announced last week.

The meltwater lednian stonefly and western glacier stonefly will both be listed as threatened under the Act.

The insects live in high-elevation cold-water streams on federal lands in and around Glacier National Park, Grand Teton National Park, with a population of the lednian stonefly also living on tribal lands in western Montana.

Stoneflies are aquatic predatory insects. The eggs and larval stages live under water and the adults spend a brief period of their lives out of the water where they mate and lay their eggs.

However, melting glaciers, higher water temperatures, and changes in the volume of snowmelt and runoff are degrading the habitat these unique insects need to survive.

The Service worked closely with partners including the U.S. Geological Survey, the National Park Service, the U.S. Forest Service and the Confederated Salish and Kootenai Tribes to help determine the best available science regarding this decision. Most remaining glaciers and snowfields in Glacier National Park, one of the primary locations where these species are found, are predicted to completely melt by 2030, the Service noted in a release.

The Service first considered the insects for listing back in 2011.

Clint Muhlfeld, a research aquatic ecologist with the U.S. Geological Survey has been studying the stoneflies and climate change in the Glacier Park for years.

He noted other than the polar bear, they’re the only species listed under the ESA due to climate change that he knew of.

“They’re the polar bear of Glacier (Park),” he said of the insects.

The stoneflies don’t rely entirely on glacier meltwater for survival. They’ve also been found in the Park in streams that have a cold groundwater source, like subterranean ice, or permanent snowfields. Stoneflies in general are a harbinger of water quality — they don’t survive in streams that have pollution or high water temperatures.

The problem is that as the world continues to warm, the stoneflies’ habitat will shrink, resulting in isolated populations that are prone to extinction. The insects fill a niche in the high mountain habitat of the Park.

From a conservation standpoint, the insects are already in protected habitat and they’re already living in the highest terrain in the continent, so moving them really isn’t an option.

However, Muhlfeld said they plan on doing some research this summer in Banff National Park to see if the stoneflies live there and if there’s suitable habitat.

These stoneflies prove the resiliency of life itself. Living below a glacier or snowfield in streams that are brutally cold, dark for months at a time and see huge swings in flow and turbidity, is remarkable in and of itself.

“They’re occupying some of the harshest environments on Earth,” Muhlfeld noted.

Conserving mountain species like stoneflies will require lowering carbon emissions, Muhlfeld noted.

In some cases, species can be moved, which at least gives them a respite for awhile in an increasingly warming world. The Park has been doing that with bull trout, another species that requires cold, clean, water to survive.

For example, Glacier recently moved bull trout into Grace Lake, a high mountain lake that previous didn’t have bull trout. Grace Lake offers protection from non-native lake trout as well, since it is above a waterfall that acts as a fish barrier.

The Park is also working on a similar project with native westslope cutthroat trout in Camas and Evangeline Lakes, Cutthroats are also threatened by climate change and hybridization with non-native rainbow trout and Muhlfeld and fellow scientists are also looking at lakes and streams on the east side of the Park for possible native trout preservation.