At that point, internal overheating spikes, which can cause reproductive failures or worse. Yet at some point, their panting becomes insufficient to offset the heat generated by their high metabolic rates. When birds overheat, they begin to pant to cool down. Rather than looking at indirect effects of warming on food supply, she and her collaborators wanted to learn how heat directly impacts the physiology of these birds.Īrctic animals, such as murres and buntings, have high metabolic rates, a great adaptation for generating heat in cold climates, Choy said, “but, of course, that’s a disadvantage when you’re in the heat.” Choy said her research differed from that of researchers who studied those mass die-offs. Mass die-offs of the common murre, a closely related species, in which tens of thousands of the birds washed up dead on the shores of Alaska and the west coast of North America in 20, were attributed to a marine heat wave in the Pacific Ocean that sent negative effects cascading throughout the food web. “Arctic birds such as thick-billed murres could be canaries in the coal mine for the effects of climate change.” The Arctic, which is warming more than two times as fast as the rest of the world, is an early warning system for the effects of climate change, Choy said. In short, “very, very poorly,” Choy said. Choy researched how well these seabirds can cool down when temperatures rise. Credit: Douglas Noblet ‘Canaries in the Coal Mine’īecause of murres’ black backs, their body temperature can reach nearly 115 degrees Fahrenheit (46 degrees Celsius) in the sun, even on a 75 degree day. Their food source is currently shifting as fish from southern waters move northward. “Our study is the first to look at heat stress in a large Arctic seabird it might be a very important but underreported source of stress.” Thick-billed murre parents on Coats Island, Nunavut split the duties of attending to their nest and fishing in 12 hour shifts. “There has been very little work done on the direct effects of heat on Arctic species,” Choy said. Scientists are concerned about what the resulting changes in behavior and physiology will mean for the long-term existence of Arctic species and what happens when those shifts interact with other factors, such as habitat loss. In the 2018 Arctic Report Card, the National Oceanic and Atmospheric Administration identified a more than 50 percent decline in the herd size of caribou, which to manage heat stress, in addition to panting, rely on dwindling patches of snow left over from winter. Large mammals and cold-blooded species, like fish, may also be at risk, as temperatures rise to levels that exceed their ability to cope with heat.
“I mean the buntings can’t go any farther north,” O’Connor said.īirds aren’t the only animals at risk for heat-related stress and death. Can animals keep pace with climate change?” said Ryan O’Connor, a postdoctoral fellow at the Quebec Center for Biodiversity Science at the University of Quebec at Rimouski, who does research on snow buntings for the ArcticSCOPE project.įor murres and buntings, the answer to this question is tricky. Scientists want to know which species will be able to adapt to the hotter conditions of the High North, either through evolution or changed behavior, and which ones won’t. As extreme heat waves become more frequent and rapid warming threatens northern latitudes, the same adaptations that have allowed animals to survive cold temperatures are the ones that may make them more susceptible to heat. Heat stress is an emerging focus of Arctic research. Her research, which found experimental evidence of murres’ susceptibility to heat stress, appeared earlier this month in the Journal of Experimental Biology.Ĭhoy’s study was part of a Canadian-based project called ArcticSCOPE, which is investigating the direct impacts of heat on two Arctic bird species, thick-billed murres and snow buntings, which are songbirds. A combination of overheating, intense mosquito attacks and the murre’s dedication to protecting its sole egg of the year appeared to be to blame.īut Choy’s research focused on a different potential cause of the birds’ mortality: exceptionally low physiological tolerance for heat. Researchers from Coats Island, near Nunavut, Canada, had reported finding dead murres still perched atop their nests after warmer temperatures in 2011 and before that, in the late 1990s. The laughing calls of more than 60,000 thick-billed murres surrounded her.Ĭhoy, a postdoctoral researcher at McGill University, hoped to capture a live murre in order to take it back to a remote field lab and test its tolerance for heat. In 2019, Emily Choy rappelled off the side of a guano-covered cliff almost 400 feet above Hudson Bay, and reached for a sleek black-and-white seabird.
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