Earth Notes: Burrowing Mammals and Desert Heat
It’s been known for a long time that many small mammals adapt to the desert’s heat by burrowing underground. New research shows that adaptation may give them resilience in the face of the West’s warming climate.
A team of ecologists revisited detailed data taken in the Mojave a century ago by naturalist Joseph Grinnell. They compared those with modern field surveys in national park areas, as well as computer models, to measure changes in mammals and their avian counterparts.
The Mojave Desert—already the hottest, driest desert in the country—is growing hotter and drier. The research shows small animals appear to be faring better than birds in adjusting to harsher conditions.
Populations of small mammals like cactus mice, kangaroo rats, and white-tailed antelope squirrels have stayed relatively stable. But birds in the Mojave are showing sizable declines, mainly because they’re active in the daytime heat and less able to get water.
With cooler temperatures a foot down in the soil, the microhabitat protects burrowing animals from potentially deadly heat and aridity. They’re able to lower their “cooling costs” by avoiding the baking sun and emerging at night when temperatures are more favorable.
Eric Riddell, an ecologist at Iowa State University and lead author on the study, says as global climate change brings the threat of extinction for some species, it’s important to learn how small shifts in behavior may help others survive.