There's a change in the weather and that's not good news for almost 400 bird species.

That's the conclusion of a report released this month by the National Audubon Society.

The report, “Survival by Degrees: 389 Bird Species on the Brink,” shows that 389 North American bird species — nearly two-thirds of those studied — are vulnerable to extinction due to climate change.

Jim Bonner, the executive director of the Audubon Society of Western Pennsylvania, said the report took two years to write and used 140 million different data points compiled by Audubon Society members and other birders.

“It drew upon eBird reports submitted by birders, the Christmas Bird Count and Operation Feeder Watch,” said Bonner.

The eBird reports go into a large database recording data such as time, location and number of birds spotted.

Bonner said, “We are collecting data all the time. This is citizen science. All of us helped make this report.”

Audubon scientists took these observations to pinpoint where 604 North American bird species live today — their “range.” They then used the latest climate models to project how each species' range will shift as climate change and other human impacts advance across the continent.

Bonner said while there were a number of different variables considered, not all would affect bird species in Butler County or in Western Pennsylvania, such as a rise in sea levels. But others definitely would.

Some are already appearing in the county.

Bonner said, “One of the local dangers is false springs as the temperature warms up a bit.

“We have had warm days in February and March, and then plants start to bud. Then there is a freeze in March or April and it stunts the plants,” he said. “Migrating birds when they arrive in the area find no food.”

The recent heavy rainfalls are also putting pressure on local bird populations.

Downpours wash away the eggs of ground-nesting birds and collapse the nests of low-nesting birds.

The results are clear: Birds will be forced to relocate to find favorable homes. And they may not survive.

“Birds may be able to move into cooler areas or higher elevations,” said Bonner, but birds have evolved to thrive in certain environments.

“They need certain trees and shrubs to survive. Birds might have the ability to fly, but their habitat does not,” said Bonner.

If the average temperature rises 3 degrees Celsius in the near future, 19 bird species in Butler County will be in danger.

“For instance, the wood thrush,” said Bonner. “Everyone knows its call, the flutelike sound we hear in the summer and spring.

“And the ruffed grouse might be the state bird of Pennsylvania, but there might not be any in the state by 2050,” he added.

And it's not just bird species that are under threat, according to David Krayesky, associate professor of biology specializing in botany at Slippery Rock University.

“As the climate changes and weather gets warmer, species that require cooler temperatures run the risk of being extirpated in Pennsylvania,” Krayesky said.

He said there are pockets of the environment that provide habitats for species of flowering plants and lichens that are already diminishing.

Bonner cited milkweed as a plant whose seeds need to freeze for them to germinate.

And while climate change is cited as the reason for populations of plants and animals to decline, it might be the reason other less welcome populations are on the increase.

Higher temperatures throughout the winter limits the number of freezes that can reduce the number of ticks, mosquitoes and other insect pests.

The Audubon report “absolutely sounds credible,” said Julie Snow, a professor of geography and an atmospheric chemist who teaches climate change and meteorology at Slippery Rock University.

Snow said the difference between a rise in temperature of 1.5 degrees Celsius and 2 degrees Celsius is significant.

It's the difference between 20 percent of the world's coral reefs surviving at 1.5 degrees warmer and zero percent survival at 5 degrees warmer, she said.

The clock is running on preventing or even limiting climate change.

“We have about 10 years to get our carbon emissions down,” said Snow.

Snow said the main reason for the changing climate is simply fossil fuel emissions dumped into the planet's atmosphere by mankind's actions.

That's certain, she said. What's uncertain is how humans will respond to this.

“I have a hopeful part, but I don't know,” she said. “I'm looking into the future and I have climate anxiety. It's horribly depressing.”

But mankind can't say that it hasn't been warned.

“The birds are telling us something and we should listen,” said Bonner of the Audubon Society. “It's the proverbial canary in the coal mine.”

According to the Audubon Society, highly and moderately vulnerable birds may lose more than half of their current range — the geographic area where they live — as they are forced to search for suitable habitat and climate conditions elsewhere.The following bird species that nest or spend the winter in this area most vulnerable across their entire range:Eastern whippoorwill- Red-headed woodpecker- Blue-headed vireo- Fish crow- Wood thrush- Brown thrasher- Field sparrow- Savannah sparrow- Henslow's sparrow- Eastern towhee- Bobolink- Worm-eating warbler- Golden-winged warbler- Cerulean warbler- Chestnut-sided warbler- Pine warbler- Yellow-throated warbler- Black-throated green warbler- Scarlet tanager