Western Pennsylvania experiencing same bird declines being seen nationwide
Recently released researched confirmed what local bird experts already suspected: Bird populations have dropped a staggering 29% — nearly 3 billion birds — since the 1970s, according to the journal Science.
Jim Bonner, executive director of the Audubon Society of Western Pennsylvania headquartered in Fox Chapel, said he is, sadly, not surprised.
“The study gives detail for what people have been saying for a while,” he said. “For years during migration people have been saying they are not seeing the birds like they used to.”
Then there specific birds like the evening grosbeak that are a much rarer find in the region.
The overall decline is what is significant, according to Lucas DeGroote, avian research coordinator for Powdermill Nature Reserve in Rector, which is a part of the Carnegie Museum of Natural History.
“We’re catching about 25% less birds than we did when we started bird banding in 1961,” DeGroote said.
Like many birders, DeGroote has witnessed the decline first hand. When he was still in college driving around at the Magee Marsh Wildlife Area along Lake Erie, the bird migration Mecca in Ohio 20 years ago, the trees were “dripping with warblers” on good migration days.
“I don’t see those numbers anymore,” he said.
Local birders who participate in surveys have witnessed the bird population decline, evident with some species documented in the Christmas Bird Count, sponsored by the National Audubon Society.
The Christmas Bird Count was one of many studies used in the journal Science study.
In Southwestern Pennsylvania, there has been almost a 33% drop in the population of the white-breasted nuthatch between the periods of 1986-95 and 2008-18, according to Bonner.
“Does that mean all the nuthatches have moved north?” Bonner asked. “We’re such a small piece of the big puzzle.
“The larger study confirms what we’re seeing and confirms this mega trend.”
According to the journal Science study, 90% of the birds lost are from 12 bird families. They include common and widespread species such as sparrows, swallows, warblers and finches.
Declines in the abundance of common species may not seem as dramatic as the endangerment of rare ones, but it’s a very serious form of ecosystem erosion, the scientists said.
That’s because abundant species often play important roles in their biomes, whether they control pests, pollinate flowers, disperse seeds, provide food for other animals.
That’s not to mention contributing to the natural beauty of an area that draws tourists who support local economies.
“When you’re losing abundance, you’re losing the fabric of the food chains, the fabric of the ecosystems — more perhaps than losing one rare species,” said lead author Kenneth Rosenberg, a conservation scientist at Cornell University and American Bird Conservancy.
Rosenberg and his colleagues analyzed more than a dozen bird survey data sets that covered 529 bird species across a host of ecosystems in the U.S. and Canada. These data sets, such as the North American Breeding Bird Survey, rely on citizen scientists to conduct counts along roadsides across North America every year, and boast records going back decades.
The researchers were also able to track feathered fliers with a network of 143 weather radars, which often catch migrating birds on their nighttime routes.
The researchers did not weigh in on the causes for these declines.
But other work has pointed to habitat loss because of urbanization, pollution, pesticides, and the intensification and expansion of agriculture as likely culprits, Rosenberg said.
There were a few success stories in the data that could offer a road map for aiding other bird populations, Rosenberg said. Wetland birds, such as ducks and geese, have increased, primarily because of conservation efforts that protected wetland habitats over the last few decades.
Much of that conservation was driven by hunters, who wanted to maintain healthy populations, he added.
And raptors such as bald eagles, ospreys and peregrine falcons have also improved since the 1970s, when their numbers had been decimated by the use of the pesticide DDT. It was banned for agricultural use in 1972, and laws that protected the birds of prey allowed them to recover.
Mary Ann Thomas is a Tribune-Review staff writer. You can contact Mary at 724-226-4691, [email protected] or via Twitter .