How Glacier’s stonefly can help fight climate change.
By Jennifer Bogo
The polar bear may be the biggest, most charismatic animal threatened by global warming, but odds are it won’t be the first species the federal government recognizes for that reason. That honor could go to an unassuming insect: a stonefly, located in the remote alpine streams of Montana’s Glacier National Park.
The meltwater lednian stonefly, or mist forestfly, thrives in alpine springs and other freezing-cold waters formed by melting glaciers and permanent snowpack. The species earned its scientific name, Lednia tumana, for the ice (Russian “led”) and mist (Russian “tuman”) surrounding the Many Glacier area, where adult specimens were first collected in the early 1950s. Their larvae—red-brown, gill-less bodies less than an inch long—spend the winter clinging to the underside of rocks in streams that are typically below 0 degrees Celsius and covered by 12 or more feet of snow.
Like most insects, the mist forestfly lacks glamour, and thus attention and funding. As a result, not much else is known about it. Lednia tumana have been reported in just two streams in Glacier and in one across the Canadian border in Alberta’s Waterton Lakes National Park. Its range may also extend south into Montana’s Bob Marshall Wilderness and as far north as Banff and Jasper National Parks in the Canadian Rockies.
What scientists can say with increasing confidence is that the insect’s habitat won’t remain ice-cold for very long, and it could eventually dry up. “Historically, the park had about 150 glaciers, and now we’re down to 25,” says Dan Fagre, who works for the U.S. Geological Survey inside Glacier National Park. What’s more, the rate of glacial ice loss today is three to four times that in the 1960s. Although previous computer modeling indicated the park’s glaciers would be gone by 2030, new data suggest they are on a trajectory to vanish in just 10 years. “Our snowfields are disappearing along with the glaciers,” Fagre says. “They’re all part of the same phenomenon.”
That phenomenon is, of course, global warming. Rates of precipitation in Glacier National Park haven’t changed significantly, but temperatures have, particularly in the winter, when glaciers and snowpack build insulation for the summer season. Like other temperate mountain areas, the park has warmed at two to three times the global average.
Alpine aquatic ecosystems rely on a particularly delicate balance of late-season snow and ice melt. “Many other species occur in these same types of streams that Lednia occurs in,” aquatic taxonomist Joe Giersch says—including a rare caddisfly and an even rarer crustacean that dwells primarily in the groundwater beneath the Earth’s surface. “It’s really a whole ecosystem we should be concerned about, rather than just one species.”
In August 2009, the U.S. Fish and Wildlife Service (FWS) listed Lednia tumana in a group of 29 species deserving of a full-status review under the Endangered Species Act. The stonefly passed the first hurdle for federal protection because of “climate-change-induced glacier loss,” according to the Federal Register. In late December, the group WildEarth Guardians sued the agency, hoping to force a decision on the species’ listing—a decision that is now nearly two years overdue.
Even if the agency declares Lednia tumana endangered, it won’t be enough to rescue the species. There’s already too much momentum in the climate system to prevent glacier loss, Fagre says. The glaciers could eventually re-form, as they have in the past—“it’s just not going to be in our lifetimes,” he says.
But adding the stonefly to the endangered species list might help tackle the bigger problem of global warming, because the Endangered Species Act isn’t necessarily designed to save just one species. “It’s an important tool in the toolbox for fighting climate change that we’ve had all along,” says Nicole Rosmarino, wildlife program director for WildEarth Guardians. The FWS would have to designate critical habitat that the species needs to survive and recover, she reasons. And while the park has no control over melting glaciers or reduced snowfall, to some extent, the federal government does. “The Fish and Wildlife Service would finally have to decide the extent to which it can use the Endangered Species Act to regulate greenhouse-gas emissions,” Rosmarino says.
Climate change is rippling across the landscape in other ways, too, causing insect outbreaks, more intense wildfires, and plant migrations. “Everything in the mountain ecosystem is being affected,” Fagre says. “It turns out that glaciers are simply the most visible manifestation of that.”
But other species still have time to recover, including animals like pikas, wolverines, bald eagles, and grizzly bears—all of which are tied to climate cycles through habitat and prey. And their collective fates may be linked to protecting something invisible to most park visitors: a humble stonefly.