PICTURE A CHUBBY, HAIRY CREATURE that looks like a tailless squirrel, popping up from the talus on the high Olympic slopes. It calls at you in short, high-pitched bursts, sounding like a kid with a neon whistle at a warehouse rave. The animal is a dusty yellow, the size of a well-fed house cat, and sports the paunch of a middle-age couch potato—this is the Godzilla of squirrels. It’s Marmota olympus, our own special marmot.

This summer, more than 100 volunteers will scour Olympic National Park for evidence of the creatures. When a grad student discovered several years ago that the marmot population here was dwindling, park staff were faced with an ecological mystery and few resources to solve it. Enter the marmot monitors.

"Volunteers augment the funding crunches," says park biologist Patti Happe. "We can’t keep on top of everything." Buoyed by the Washington National Park Fund, last year more than 80 volunteers turned weeklong backcountry trips into scientific excursions. They checked 260 sites in the park‚Äôs remote interior, armed with a GPS device and a radio, finding marmots at a little less than half of them.

So why are the rodents of unusual size disappearing? "We think there’s an unsustainable level of coyote predation," says Happe, but they need cold, hard numbers before they can act. Aside from the statistics, she’s thrilled to see the program take off—this year volunteers joined a wait list to participate, happy to donate a week to the park’s cause. "I want good data, but this is your vacation," she says. "I want you to have fun."