Extreme temperatures threaten desert songbirds with death by dehydration
According to NASA, 2016 was the hottest year on historical record. Globally, the increase amounted to nearly 1.8 degrees Fahrenheit. And while that might not sound like much of an increase, it could mean the difference between life and death for some bird populations.
Heat waves due to climate change pose an increasing threat to wildlife in many regions of the world. During heat waves, birds are especially at risk of lethal dehydration due to scarce water resources and high rates of evaporative water loss needed for cooling their bodies. High environmental temperatures were attributed to recent mass die-offs of wild birds and poultry in Australia, South Africa, India and North America suggest that birds are sensitive to extreme heat events.
With climate projections forecasting a large increase in the frequency, intensity and duration of heat waves, researchers including Tom Albright, associate professor from the Geography Department at the University of Nevada-Reno, Professor Blair Wolf from The University of New Mexico Department of Biology, and Alexander Gerson, assistant professor, Department of Biology, University of Massachusetts-Amherst, and others mapped the potential effects of current and future heat waves on the risk of lethal dehydration for songbirds in the southwestern United States.
The research, “Mapping evaporative water loss in desert passerines reveals an expanding threat of lethal hydration,” was published today in PNAS. The research was funded through a three-year, $650,000 National Science Foundation grant. NASA also funded aspects of this research, and its data and products played a role in enabling the research.
“Birds are susceptible to heat stress in two ways,” explained Wolf. “When it’s really hot, they simply can’t evaporate enough water to stay cool, overheat and die of heat stroke. In other cases the high rates of evaporative water loss needed to stay cool deplete their body water pools to lethal levels and birds die of dehydration; this is the stressor we focused on in this study."
“This is a neat example of the kind of science enabled by two of our great U.S. science agencies: NSF (Blair’s team) and NASA (Albright’s team): basically mapping what you might call physiological performance and ultimately mapping the dynamics of risk,” said Albright.