Two-thirds of bird species in North America are at risk of extinction because of the climate crisis, according to a new report from researchers at the Audubon Society, a leading US conservation group.
The continent could lose 389 of the 604 types of birds studied. The species face threats to their habitats from rising temperatures, higher seas, heavy rains and urbanization.
Those at risk include the wood thrush, a well-known songbird, and the Baltimore oriole, the mascot of Maryland’s baseball team. The recognizable common loon could disappear, as could the vibrant mountain bluebird.
Bird extinctions are yet another face of the human-caused biodiversity crisis threatening up to a million animal and plant species. A related study from Cornell University last month found the US and Canada lost one in four birds – or 3 billion total – since 1970.
“Birds are indicators of the health of our environment, so if they disappear, we’re certainly going to see a lot of changes in the landscape,” said Brooke Bateman, the senior researcher who wrote the report. “If there are things changing with birds we have to understand that the environment is changing for us as well.”
Bateman said birds are an excellent lens for viewing environmental destruction, because they are visible and respond quickly. In the 1970s, humans realized the pesticide DDT was dangerous when birds were unable to successfully breed, she noted.
Birds pollinate plants, control insects and help forests flourish, so their disappearances could have ripple effects.
The report examined 140m records of birds’ current habitats from more than 70 sources, including sightings from birdwatchers. It used climate modeling from the United Nations’ Intergovernmental Panel on Climate Change to determine which birds might be forced to relocate.
Researchers considered any bird species that would lose much of its range to be at risk of extinction. All 16 of the Arctic bird species studied are highly vulnerable to extinction, for example.
The planet has already warmed 1C (1.8F) and is on track to heat up by at least 3C (5.4F) because of the way humans live.
In that severe scenario, North America could lose 389 species of birds, or 64%. But if the world can hold heating to 1.5C (2.7F), the number of at-risk birds would decrease to 241 species, or 40%.
In either case, bird lovers will notice the difference. Bateman explained that her five-year-old daughter will hear a different baseline of birds than she did herself when growing up.
“What I would expect to see with climate change, especially around areas with a lot of people is … a homogenization of species you’re seeing,” Bateman said.