The American Pika - An indicator species for Global Climate Change

[Dave Stiles]

I spent the day with a small population of 22 Pika's located in the Gros Ventre Landslide debris pile. On June 23, 1925, huge amounts of rock and debris cascaded down the north slope of Sheep Mountain, changing the area forever. The Gros Ventre Slide is some 50 million cubic yards of sandstone, limestone, shale and rock, about one mile long, 2000 feet wide and several hundred feet deep in places, that plunged down and formed a dam 225 feet high and half a mile wide across the Gros Ventre River near Kelly, Wyoming.

American pikas are smaller relatives of hares and rabbits, but have short, round ears. They are grayish-to-brown mammals frequently seen hunched up on boulders of nearly the same color. They have no visible tail and typically measure 6 1/5 to 8 1/2 inches and weigh between 4 and 6 1/3 ounces. American pikas feed primarily on grasses and herbs. Since food is difficult to obtain in winter in the alpine environment, pikas cut, sun-dry, and later store vegetation for winter use in characteristic 'hay piles' on a rock in talus areas, and pikas are sometimes observed gathering wildflowers.

American pikas have a vocal repertoire that consists of a series of peculiar short squeaks. They are active only by day and do not hibernate in winter. Pikas are colonial, and each pika has its territory within the colony. Pikas are often called 'ecosystem engineers' because of their extensive haying activities. They breed in spring and possibly in summer, and their young are born between May/June and July/August, usually with between two and five in a litter. The gestation period is about 30 days.

The American pika, a small flower-gathering relative of the rabbit, may be one of the first mammals in North America known to fall victim to global climate change if heat-trapping emissions are not reduced soon. As temperatures rise due to increasing emissions of heat-trapping gases, many alpine animals are expected to seek higher elevations or migrate northward in an attempt to find suitable habitat. Yet, American pikas in these regions have little option for escape from the pressures of climate change because migration across low-elevation valleys represents an incalculably high risk and perhaps an impossibility under current climate regimes for them. Results from the study suggest that climate may be interacting with other factors such as proximity to roads and smaller habitat area to increase extinction risk for pikas, creating harmful synergistic effects.

The pikas' particular vulnerability to global climate change is due to several factors. American pikas cannot easily migrate in response to climate change, as their habitat is currently restricted to small, disconnected "habitat islands" in numerous mountain ranges. Although talus within mountain ranges is often more continuous, this is not always the case; some ranges only have habitable talus at lower elevations or in broadly separated patches. Furthermore, American pikas generally do not appear to move large distances, as many individuals may spend their entire lifespan within a half-mile radius. Pikas do not inhabit burrows which could mitigate extreme temperatures and are highly active above ground during the hottest months of the year.

[Equilibrium]

Great photos!!! Isn't the pika real close to being listed as an endangered species? Something about not enough snow to provide protection for them so they're beginning to freeze to death in winter?

[Dave Stiles]

Pikas are not only threatened by the loss of the insulating snow pack in the winter, which leaves them exposed to cold snaps, but also by rising temperatures in the summer. The dense coat that protects them in winter makes them vulnerable to heat stroke during the summer months. Exposure to temperatures above 80f for over six hours is fatal to them. Rising temperatures caused by greenhouse gas pollution have already led to dramatic losses of lower-elevation pika populations. More than a third of documented pika populations in the Great Basin mountains of Nevada and Oregon have gone extinct in the past century as temperatures warm, and those that remain are found an average of 900 feet further upslope.

[Equilibrium]

I thought I read something about them. Doesn't sound good at all. Are there any areas north where they've been extirpated that might be able to better support a colony?

[Dave Stiles]

Pikas are native to cold climates, mostly in Asia, North America and parts of eastern Europe. The American pika can be found in western North America from central British Columbia in Canada to Oregon, Washington, Idaho, Montana, Wyoming, Colorado, Nevada, California and New Mexico. All but 2 of the 19 existing species of pika occur in Asia, where they probably originated.