Plenty of good habitat left in the Colorado Rockies, researchers conclude
By Summit Voice
FRISCO — New surveys by Colorado wildlife biologists suggest that pikas seem to be holding their own as temperatures rise in the Rocky Mountains. The study found that pikas remain well distributed in the Colorado high country.
“In their primary habitat, mainly at and above timberline where there is lots of talus, we find pikas almost everywhere we look,” said Amy Seglund, a species conservation biologist for Parks and Wildlife based in Montrose.
Seglund conducted a major research project to determine the health of pika populations in Colorado in 2008. Her field crew surveyed 62 historical locations across the state to determine the presence of pikas. The animals were found in more than 90 percent of those sites — almost everywhere there is suitable habitat.
Since the original surveys were completed, more than 900 occupied sites have been documented by Colorado Parks and Wildlife.
“We were even finding them in these little talus areas and at lower elevations where I never guessed pika would have lived,” she said.
The Colorado Parks and Wildlife study findings are similar to conclusions reached in an earlier study by University of Colorado, Boulder researcher Liesl Erb, who found that localized population declines appeared to be linked to dryness rather than directly to temperature.
Erb’s team assessed 69 historical sites known to host pikas in a swath of the Southern Rockies ranging from southern Wyoming through Colorado and into northern New Mexico. The results showed that 65 of the 69 historical sites that had hosted pikas — some dating back more than a century — were still occupied by the round-eared, hamster-like mammals, Erb said.
The American pika lives in mountainous regions including British Columbia, Washington, Oregon, Idaho, Montana, Utah, Wyoming, Colorado, Nevada, California and New Mexico. Members of the rabbit family, the conspicuous pikas can be seen scurrying about rocky debris known as talus in alpine and subalpine regions of the Rockies, emitting their signature, high-pitched squeaks. Instead of hibernating, pikas cache huge amounts of plants and flowers known as hay piles under large rocks that sustain them through the long winters.
A 1990 study showed that the average weight of their “haystacks” is 61 pounds; and that in a 10-week time period one pika will make 14,000 foraging trips – 25 per hour – to secure its food stash.
Reports of global warming threats to pikas emerged in the early 2000s, when research in Nevada showed that global warming was the likely cause of the extirpation of some pika populations in the Great Basin.
Seglund explained that the mountains in the Great Basin are much different than Colorado’s: They are at a lower altitude, provide limited contiguous habitat, receive less moisture and hold warmer temperatures.
In Colorado there’s more available habitat, more moisture, and the summer-time temperatures are cool enough for pika to thrive. The vast majority of the available habitat for pika in Colorado is on high-elevation public land that is not heavily impacted by roads, grazing and other human activity. With few human activities nearby, pika habitat won’t be subject to fragmentation which disturbs natural connections between populations.
In the summary of her study, published in 2010, Seglund wrote: “… Though the climate may be changing in the Southern Rocky Mountains, it currently appears that climate conditions in the state fall into the realm of temperature and precipitation cycles appropriate for maintaining healthy pika populations and distribution.”
Partly based on Seglund’s research, the U.S. Fish and Wildlife Service decided not to list the pika under the Endangered Species Act.
Colorado Parks and Wildlife continues ongoing monitoring of pika populations and their habitats at 30 established sites around the state.
“The suggestion that pika were in trouble in the West is what spurred our research,” Seglund said. “This was a very important study that helped us establish a clear picture of the current state of pika populations. Global warming will present challenges for many animal species, but our study shows that Colorado’s pika populations, for now, are in good shape.”