Pikas doing well in Glacier

It looks like a cute little rat, but is related to the rabbit, and while it lives in some of Glacier National Park's harshest terrain, it doesn't hibernate.

It's the American pika and the affable creature is doing well in the Park, according to researcher Lucas Moyer-Horner, a doctoral student from the University of Wisconsin-Madison.

Moyer-Horner and his team have been documenting pikas and their habitat in Glacier since 2007.

Last week he presented some of his results. The most notable finding that there are at least 1,500 pikas in Glacier and a "ballpark" of 3,000 to 4,000 total — a healthy number considering that in other parts of the U.S., the animal has gone extinct.

Some historical pika populations in the Great Basin region have been extirpated in the past 100 years. Scientists believe it's due to climate change — pikas simply can't take the heat or the cold.

The potato-sized critters don't do well in temperatures over 80 degrees and they need deep snows in the winter to keep from freezing to death. Moyer-Horner noted studies have shown that a pika in a trap where temperatures have reached an ambient temperature of 78 degrees for longer than a half hour have perished. A pika's body temperature is always about 104 — but if that temperature gets up to 109, they die.

In Glacier they beat the heat by going under big rock piles called talus slopes where the shade of the stones keeps them cool. They also need deep snows in the winter to provide insulation from the cold. Pikas build big mats of vegetation called haypiles under large rocks during the summer. Haypiles provide food through the winter months. Pikas will also feed on their own feces as well as feces from other animals — notably hoary marmots.

PIKAS ARE solitary animals. They can have two litters, though late litters have a low survival rate. Pikas in general have a high mortality rate — 37 to 47 percent. They're susceptible to predation and because talus slopes are often isolated, a young pika that is shoved out of its natal habitat may have to migrate a long distance to the next talus slope.

Pikas are seen as an important bellwether nationwide for climate change. Raise temperatures too high in the summer and they die. Not enough snow in the winter and they freeze to death. In the Great Basin, populations that used to live at lower elevations have perished — likely from rising temperatures.

Moyer-Horner's work will provide important baseline data to monitor populations in the Park. Previous data was largely anecdotal. His is the first parkwide survey of the Park.

All told, crews surveyed about 200 talus slopes in Glacier. Pikas only live in talus slopes. He found that while they would live in warmer slopes that faced south, they had higher densities in slopes that faced north.

In Glacier, elevation also played a role. Pikas populations were at their highest density in slopes between 7,00 and 7,500 feet elevation. Below that, density dropped and above that, density was less as well.

With their temperature sensitivity, Moyer-Horner's crews also found that pikas were most active early and late in the day.