Cool critters: Meet G. spokanistan, the unique cold-loving insect living on Mount Spokane

Seasonally cold temperatures and snow finally moved into the Inland Northwest this month. Skiers are happy. And so is a rare insect known as an ice crawler. While most bugs go dormant during cold weather, these fellas thrive in it. In fact, some of them are scuttling about on Mount Spokane as you read this.

Ice crawlers are seldom seen due to their rarity, preferred habitat of ice and snow, and their nighttime forays. Although these cold-loving creatures have been around for millions of years, according to fossil records, they were only formally identified 110 years ago.

Then, in 1994, a population of these inch-long, wingless insects was discovered living on Mount Spokane. Local entomologist and wildlife consultant James Bergdahl found them by accident while surveying for beetles.

“When I saw one, it was a big surprise,” Bergdahl recalled of the caramel-colored, elongated insect no larger than a paper clip. “Even though they’re rare and infrequently collected, lo and behold, I discovered a population not far from Spokane.”

A surprise, indeed. In 2016, The Spokesman-Review published a story about Bergdahl’s discovery and its scientific implications.

Ice crawlers, from the family grylloblatidae, are a “highly unusual group of insects,” a team of scientists concluded in an international study published in the Journal of Insect Biodiversity in 2014. Not only do these arthropods yearn for cold temperatures, but they’re very selective about where they live. For them to survive, the climate and terrain have to be just right.

Consequently, they inhabit small pockets of higher-elevation landscapes in Siberia, Japan, China and western North America – which happens to include the top of Mount Spokane.

“The population is most dense in the forested area near the summit,” close to one of the new downhill ski runs, Bergdahl said.

During winter, ice crawlers spend a lot of time under snow, mostly emerging at night to forage for dead insects and plant matter carried by the wind.

“The ideal temperature for them is near freezing,” said Bergdahl, adding that they retreat under logs and into crevasses to stay cool in summer.

Another oddity? Ice crawlers can live to the ripe age of 10 or even longer, a much longer lifespan than most insects, he explained.

Not only does this unique insect live near Spokane, but it may not exist anywhere else in the world, according to ice crawler expert Sean Schoville of the University of Wisconsin-Madison, who analyzed the DNA of insect samples submitted by Bergdahl.

“It likely represents a distinct species,” said Schoville, who visited Mount Spokane to canvass the area where the ice crawlers were discovered. While there, he and Bergdahl found even more crawlers.

Since Bergdahl discovered the insect nearly 31 years ago, it has been tentatively named Grylloblatta spokanistan. In 2018, G. spokanistan made an official appearance in scientific literature when Schoville published the insect’s genetic analysis in the journal of the Royal Entomological Society.

More work is needed for it to be definitively ranked as its own species, Schoville explained. Also important is how G. spokanistan and other ice crawler species have evolved so innovatively and how they’ll respond to climate change, he said.

In the meantime, the insect continues to thrive in temperatures that would send most insects into a torpor-like state or kill them.

“Ice crawlers thrive in a frozen world, where the vast majority of animals – including humans – would struggle to survive,” Schoville said.

Ah, yes. Survival. It’s possible that this strange, freeze-tolerant insect that resembles an earwig lived in the previously glaciated area of Mount Spokane during the last Ice Age, Bergdahl explained.

“More genetic studies will most likely eventually answer this question,” he said.