ALBUQUERQUE, N.M. — As temperatures climb across the Southwest,
researchers, including some from Northern Arizona University, have found some species will win, but others stand to lose big.
The U.S. Geological Survey and researchers from NAU and the University of New Mexico
released a report this week that takes a closer
look at some of the effects climate change is likely to have on species such as
the desert tortoise and the pinyon jay.
The jay stands to lose nearly one-third of its breeding range, while other
birds could lose as much as 80 percent by the end of the century. On the other
hand, the tortoise is the only reptile studied that isn’t projected to see a
decrease in suitable habitat.
The researchers wanted to provide a “crystal ball” for land managers in the
Southwest so they could make more informed decisions as conditions become warmer
and drier and vegetation changes, said lead author Charles van Riper, a USGS
ecologist in Tucson.
“Everybody wants silver bullets, but this shows there are no silver bullets,”
he said. “Each individual species is going to have its own response, and some
are going to benefit from change and others won’t.”
The study focuses on ecosystems within the Sonoran Desert and the Colorado
Plateau, but researchers also included the rest of the Western U.S., parts of
which have been grappling with severe drought for years. Birds and reptiles make
up most of the region’s biodiversity, the researchers said.
What will make or break a species’ ability to live through a changing climate
is whether they are generalists or specialists. Those creatures that nest only
in certain trees or eat very specific foods will have the hardest time.
Those species that already deal with a wide range of temperatures in the places
they live and aren’t picky when it comes to diet will benefit the most,
according to the report.
The jay, for example, depends on pinon groves throughout the high desert and
stands to lose between one-quarter and 31 percent of its breeding range as
warmer, drier conditions wipe out more pinon trees. Other birds such as the
migrating Williamson’s sapsucker and the sage thrasher could lose as much as 80
percent by the end of the century.
Land managers throughout the West already deal with numerous threatened and
endangered species _ from the lesser prairie chicken in Texas and New Mexico to
California’s desert slender salamander. Environmentalists say the study’s
findings show species that are common now could end up being just as rare as
those protected under the Endangered Species Act due to changing climates.
“We’re seeing these new emerging threats,” said Collette Adkins Giese, a
biologist and attorney with the Center for Biological Diversity.
“Originally, climate change wasn’t prompting listings. There were other
threats, but now it’s a factor that’s driving species toward extinction,” she
said. “Studies like this that have these models will help us identify those
species that are more susceptible.”