I look—and listen—for them whenever I’m in high country. American pika, precious little members of the Hare family, live in mountainous terrain in the Western United States. Because they forage near dawn and dusk, seek shelter when they sense potential predators, and are quite petite—they weigh only about 6 ounces and are no more than 8 inches long—people tend to overlook them or misidentify them as rodents.
Herbivores, pika gather grasses, thistle, sedges, wildflowers, and just about any other greenery they can reach. And though they might nibble on a blade or two of grass while out foraging, pika carry most of what they find back to their dens, where the fodder is collected and allowed to dry in “haystacks,” caches of food they live on throughout the year.
If you’re lucky enough to find a colony of American pika and stop to watch them quietly for a while, you’ll often see them perching atop a large rock with a mouth filled with the vegetation they’ve collected. Like the adorable pika featured above.
Pika have inhabited this planet for millennia. They evolved from ancestors who lived during the Late Miocene era (approximately 11 million years ago) and probably migrated to North America from north-eastern China via the now mostly submerged Beringia subcontinent.
They thrived here, finding a temperate environment and many talus slopes to colonize. But the modern age has not treated the pika kindly, and the species has been under stress for quite some time. Habitat loss has eliminated ecosystems pika used to call home and has also limited their expansion, preventing new colonies from forming. But rising temperatures pose a more significant problem for pika. The species needs cool and moist conditions and can die if exposed to temperatures above 78° F for as little as six hours.
In response to the gradual increase in global temperature that began after the Industrial Revolution, pika (like many plant and animal species sensitive to heat) moved north, to higher elevations, or both. But pika have disappeared in most of what-used-to-be their southern range, and the northern populations now live at or above 9000 feet. With global temperatures rising at an increasing rate due to climate change, they are running out of options and face likely extinction.
And they are hardly alone.
As Carl Zimmer made clear in a recent New York Times article, new studies indicate that “climate change could drive to extinction as many as one in six animal and plant species.” The study he cites (and links to) appeared in Science magazine and offers a sobering appraisal of what is likely to occur should global temperatures rise as high as most climate models suggest. But even more disturbing is the probability that the study in Science magazine “was likely underestimating the scale of extinctions” that could occur as a result of climate change.
That’s a very sad prospect for those of us who enjoy the sight of pika racing back to their dens with grass or whistling an alarm call from rocky perches.