LAS VEGAS – Climate change could be to blame for the collapse of bird populations in the desert along the Nevada-California border, scientists said.
The number of bird species decreased with an average of 43 percent in the past century survey sites over an area larger than the state of New York, according to a new study by researchers from the University of California, Berkeley.
The study shows that almost a third of the species are less common and widespread today than they ever were in the entire region.
The authors of the study, Steven Beissinger and Kelly Iknayan, point less hospitable conditions in the Mojave Desert as the probable cause.
“Deserts of california have already experienced quite a bit of drying and the warming of the earth as a result of climate change, and this would be enough to push the birds over the edge,” said Iknayan, who conducted the research for her doctoral thesis at the university of Berkeley. “It seems we are losing a part of the desert ecosystem.”
“The Mojave Desert is now nearly half empty of birds,” said Beissinger, a UC Berkeley professor of environmental science, policy and management. “This seems to be a new baseline, and we do not know whether it is stable or if it will continue to decline.”
The researchers spent three years searching for birds at 61 locations on both sides of the border, including survey sites in the Spring Mountains and in the Desert National Wildlife Refuge, just outside of Las Vegas, Las Vegas Review-Journal .
They also investigated sites in Death Valley and Joshua Tree national parks and Mojave National Preserve,
Iknayan revisited the same sites UC Berkeley biologist Joseph Grinnell and his colleagues examined between 1908 and 1947.
Iknayan and Beissinger found that areas with reduced rainfall lost more bird species than sites that still wetter.
Their findings were published earlier this month in the journal Proceedings of the National Academy of Sciences.
The researchers call it a collapse, because it occurred in the entire desert bird community.
“Studies elsewhere have found that the climate change typical places unfavorable for some birds, but opens the door for others to come,” Iknayan said. “In the desert, we are not seeing increases in any of our species except for the common raven. There are a lack of climate change winners in the system.”
Information from: Las Vegas Review-Journal, http://www.lvrj.com