Mussels baked by the billions. Insect larvae cooked inside scorched cherries. Baby birds plummeted to their deaths from their overheating nests.
But some species did just fine during the 2021 North American heat wave, according to a new study published today (March 11) in Nature Ecology & Evolution. With such events projected to become more frequent and intense due to climate change and 2026 on track to be the hottest year ever understanding these differing effects is vitally important, the researchers say.
With little forewarning, we relied on whatever studies were already under way or observations made during the event. Despite the breadth of this study, I suspect we have barely scratched the surface of the heat dome's ecological effects."
Julia Baum, lead author and biology professor at the University of Victoria
"The widespread ecological effects included an almost 400-per-cent increase in wildfire activity and negatively affecting more than three-quarters of the species studied," says co-author Diane Srivastava, professor in the UBC department of zoology and Biodiversity Research Centre.
The 2021 event, which lasted from June 25 to July 2, was one of the most intense climate change-fueled heat waves on record, with land temperatures reaching over 50C in some areas.
The researchers used remote sensing, a meta-analysis of field data, computer modelling and media reports to paint a broad picture of its effects on plant and animal species, as well as ecosystems around BC.
They found the effects on species were largely detrimental, but nuanced, changing depending on factors such as whether cover was available, a species' inherent ability to deal with heat, and behaviour including the ability to move to shade or not.
The different outcomes highlight the complexity of the ecological impact of extreme heat and underscore a call for a coordinated monitoring network.
