Two researchers have claimed that giant heat waves caused by global warming will kill off desert bird communities over the next one hundred years, and even believe that mass amounts of warming-related deaths have already begun to occur. 

Researchers Blair Wolf, an associate professor of biology at the University of New Mexico, and Andrew McKechnie, from the University of Pretoria in South Africa, have discovered that temperature increases as low as two degrees Fahrenheit can affect desert bird populations in a large way.

According to these researchers' findings, massive heat waves claim the lives of several desert bird populations because these birds release body heat by panting and evaporating water across the skin, and with increasing temperatures and not enough places for these birds to find shelter and water, large numbers are dying off due to heat stroke. 

Wolf and McKechnie found that water is scarce in deserts, obviously, and birds become inactive when temperatures rise. Since these heat waves cover large areas, the birds cannot just fly away to avoid the consequences either.

To better understand the future of these bird populations, Wolf and McKechnie have devised a

mathematical model based on the Intergovernmental Panel on Climate Change's predictions that Earth's temperature will rise 3.5 to 6.5 degrees Fahrenheit over the course of the next one hundred years. This model estimates survival rates (and supposedly future water costs for birds in this region, though no actual figures have been provided) for birds that will live during the 2080's during heat waves in comparison to those who live in the two hottest desert regions today: Birdsville, Australia and Yuma, Arizona. 

According to this model's results, small birds in the 2080's will show significantly less survival rates than larger birds due to their increased amount of water loss. As much as 30 to 40 percent of small desert bird populations could die off in this time period. Their research also shows that all birds under 100 grams will experience a decreased survival rate of 25 percent due to an increase in water loss. 

These researchers are blaming global warming for the increased temperatures that lead to heat waves, causing desert bird populations to perspire too much without enough water to rehydrate. Both Wolf and McKechnie say these increased temperatures will be overwhelming to birds, and have already claimed the lives of several desert bird populations in Western Australia and India. 

While their research has led them to these conclusions, Wolf and McKechnie admit that these results are not exactly 100 percent finished or accurate at this point. So far, their models only apply to birds that are already in hot, dry desert climates. 

"We don't have good research of these die-offs," said Wolf. "No researchers have actually been present during these incidents and no one has actually done the autopsies - so we don't even know the exact cause of death of these animals - whether it was dehydration or heat stroke.

"Our models allow for making somewhat educated guesses at this point, but real data on bird tolerances to heat and water stress are lacking."

Locals in Australia and India have reported these die-offs. Wolf and McKechnie are looking further into these dying populations to see exactly how many are being killed due to heat, and how this will affect other plant and animal species. 

"These incidents illustrate a need for more basic research on how animals function so that predictions can be made and measures can be taken to preserve our biodiversity," said Wolf. 

Wolf presented his abstract, "Climate change increases the likelihood of catastrophic avian mortality events during extreme heat waves and droughts" at the Global Change and Global Science: Comparative Physiology in a Changing World conference from August 4-7 in Colorado.