Bird species like killdeer and blackbirds start to fly north through the Pittsburgh region beginning in February. But climate change is forcing their migrations earlier and earlier.
Warmer springs lead to earlier bud burst — the emergence of new leaves at the start of each season. As a result, insects, nectar, and seeds peak earlier in the year than they have in the past.
To synchronize their migration with bud burst, birds must arrive in the region sooner. Today, for example, the wood thrush — a brown and white songbird — migrates five days earlier than it did in the 1960s, according to scientists at Powdermill Nature Reserve. At the environmental center, researchers have captured, studied, marked, and released birds for the past 61 years.
While five days may seem insignificant, Powdermill Nature Reserve’s bird banding specialist Annie Lindsay says that birds' ability to shift migration is limited.
“They're flexible enough to have been able to adapt a little bit,” Lindsay said. “But if the climate keeps changing the way that it is, they're not going to be able to adapt as much.”
Powdermill reports that some species, like the eastern whip-poor-will, have nearly disappeared from the region. In total, the Cornell Lab of Ornithology reports that there’s been an estimated loss of 3 billion North American birds since 1970. According to the state Department of Environmental Protection, Pennsylvania’s climate has undergone a long-term warming of more than 1.8° F over the past 110 years.
By mid-March, Lindsay said the eastern phoebe songbird will make its way back to southwestern Pennsylvania, followed by sparrows and kinglets. April, however, is when the majority of birds will soar through the region.
Lindsay said people can help migrating birds by putting decals on their windows — to prevent birds from accidentally flying into them — as well as putting native plants in their backyard and by keeping cats inside.
