What do mammals do when faced with climate change?
For elk or wolves, the answer is simple: Move.
For monkeys or shrews, though, moving isn’t an option.
They have to adapt. Or, more likely: die.
Those are findings based on a recent analysis by the University of Washington. Analyses like this present a picture of how wildlife will disperse (or not) when faced with changing climates.
I spoke with Carrie Schloss, a University of Washington graduate student who recently completed the analysis determining whether or not Western Hemisphere mammals could disperse when faced with climate change. Schloss and other researchers examined 493 species and their distributions, and compared that with projected shifts in their distributions from ten different climate change models.
“We found that on average 9 percent of mammal species from any given location may not be able to keep pace with climate change,” she says.
Ungulates—hoofed mammals like deer or pronghorn—were able to keep pace, as were most carnivores. Many of these species roam widely, and can easily move to a new habitat.
But tiny mammals, like moles and shrews, cannot cover large distances at once, so dispersing to a new habitat proves difficult. And, while monkeys may be highly intelligent and can move through tree tops with ease, climate change presents special difficulties for them.
“Primates live in low-elevation tropical forests, and to reach a different climate, they have to move much farther than many species,” says Schloss. “They also have a longer time between generations, so dispersing takes longer.”
In the past, large, wide-roaming critters like grizzly bears or moose have been considered the conservationist’s darlings. They needed the largest ranges to survive. They routinely had to cross roads or farm fields. Protect habitat for them, the reasoning went, and you protect habitat for the whole host of smaller species in an ecosystem.
But climate models show that may no longer be the case.
Schloss is now tackling a new analysis that will help conservationists plan for climate when protecting wildlife habitat—an analysis that will be used by the Conservancy when prioritizing areas for conservation.
“Conservation plans typically focus on the wildlife and diversity that is there now which can be a problem if species are moving,” she says. “There are factors that are not affected by climate change—and we can protect areas that contain those factors.”
Such as what she calls “abiotic diversity”—diversity in elevation, soil type, slope and geology. These factors influence patterns of biodiversity, but will not change even when the climate does.
An area near a wide-range of elevations—say, the foothills of the Rockies with desert to the south and alpine meadows to the north—allows species to move into a different temperature zone quite easily.
Contrast that with the Amazon Basin, where huge swaths of terrain may be at the same low elevation—leaving animals like monkeys little place to go if the temperature warms and vegetation changes.
“Conservation planning has generally not taken the changing climate into account,” Schloss says. “But we can use climate data and landscape features that do not change to make the best conservation decisions—whether that is protecting a migration route or incorporating soil types and geology into conservation plans.”
[Image: Wildlife like this capuchin monkey may not be able to migrate or adapt fast enough to deal with climate change. Image source: Matt Miller/TNC]