Natural History Wanderings

U.S. Fish & Wildlife Service reported

Murres are especially sensitive to changes in their food supply because they must eat a significant portion of their body weight each day to survive and respond quickly to changes in food availability. These seabirds dive up to 200 meters deep to catch small schooling fish like capelin and sand lance. When schooling fish become scarce or scattered, common murres struggle to meet their high energy demands, making them good indicators of broader changes in ocean conditions.

Working with partners, the U.S. Fish and Wildlife Service’s Alaska Maritime National Wildlife Refuge, has recently published a comprehensive study of the Alaska death toll in common murres that resulted from a significant marine heatwave in 2014-16.

Through an analysis of long-term monitoring data covering two large Alaska ecosystems, we found that the mass mortality event was several times greater than initially estimated. About half of Alaska’s common murre population – around four million birds – perished, the largest single-species wildlife die-off ever documented in modern history.

This is the first study to show that the impacts of rising temperatures, due to climate change , can be swift, intense, and long-lasting, with no recovery in sight and potentially permanent ecosystem changes.

Read more at  Monitoring the Common Murre Mass Mortality in Coastal Alaska | U.S. Fish & Wildlife Service