(CNN/Gray News) – A new report from the National Audubon Society warns North America will lose nearly two-thirds of its birds if global warming hits 5.4 degrees Fahrenheit (3 degrees Celsius).
That’s roughly 400 types of birds, including orioles, eagles, and gulls. Scientists say all of them will be vulnerable.
The research comes after a report published last month that showed the United States and Canada had lost 2.9 billion birds in the last 50 years.
Since the beginning of the Industrial Revolution in 1880, the average global temperature on Earth has increased by about 1.4 degrees Fahrenheit (0.8 degrees Celsius), according to NASA. Two-thirds of that warming has occurred since 1975.
“Our findings in this report are the fifth alarm in a five-alarm fire,” says David O’Neill, Audubon’s chief conservation officer, in the study called Survival by Degrees: 389 Bird Species on the Brink.
While it doesn’t sound like much, a degree or two change in Earth’s average temperature can have a big impact.
“A one-degree global change is significant because it takes a vast amount of heat to warm all the oceans, atmosphere, and land by that much. In the past, a one- to two-degree drop was all it took to plunge the Earth into the Little Ice Age,” NASA says.
“A five-degree drop was enough to bury a large part of North America under a towering mass of ice 20,000 years ago.”
The Audubon report calls for immediate action to slow the warming.
“It’s a combination of changes in temperature, precipitation and vegetation,” says Brooke Bateman, Audubon’s senior climate scientist.
“Birds are indicators. Birds tell us. They’re the ones that are telling us what’s going on in the environment. And so, we say at Audubon that the birds are telling us it’s time to act.”