Endangered Pennsylvania bird species comes back to life

Harrisburg, Pa. — For the first time in 60 years, common terns have nested successfully in the Keystone State.

The bird species has been facing hard times for the past two decades, but they've finally made progress.

Though never widespread — terns nest only at Presque Isle State Park in Erie County — they were once regular breeders. Historical records from the 1930s reveal there were 100 breeding pairs on Gull Point, at the east end of the park.

Human interference ultimately chased those birds off, though, so that the species was considered “extirpated” — completely lost — from Pennsylvania by 1985. A single pair returned in 1999, moving the species up to the state’s endangered species list where they’ve remained ever since. Following invasive plant control to restore beach habitat, terns have attempted to nest on Gull Point. Since 2012, 21 common tern nests have been started there but failed.

On Saturday, Aug. 17, two tern chicks fledged at Presque Isle State Park. That breakthrough — decades in the making — came about thanks to intervention and innovation.

Staff from the Game Commission’s Northwest Region office and Bureau of Wildlife Management’s Wildlife Recovery Division, Presque Isle State Park, Erie Bird Observatory and Western Pennsylvania Conservancy have worked together for decades to improve the beach habitat at Gull Point for the birds’ sake.

In recent years, it hasn’t been lack of habitat preventing terns from successfully nesting. The problem has been that, even when young terns hatched, they didn’t survive long because of the large number and types of predators that hunt on the beach. This includes hundreds of gulls, common nest predators quite willing to snap up a tern chick, that loaf nearby.

The outlook didn’t seem any better this year. A pair of terns returned to Presque Isle, but their first nest failed. They then made a second nesting attempt. But, without help, it seemed clear this nest would meet the same fate as the 21 others since 2012.

“It was time to try something new in the recovery of this species,” said Lisa Williams, Game Commission Wildlife Recovery Division Chief.

Game Commission staff, led by Endangered Bird Specialist Patti Barber, came up with the idea of building an exclosure or predator guard — think of an open-roofed fort around the nest — to keep predators out.

“It was a dicey plan,” Barber said. “With only a single nesting pair on the beach, these birds do not tolerate disturbance and are very likely to abandon the nest.”

Then, too, there was the question of whether offering such help at all was the right way to go. With responsibility for managing 480 species of birds and mammals in an interconnected food chain, the Game Commission does not typically step in to help one species of wildlife avoid predation. But, in this unique case — one nest on a barren beach with very little protective cover, with literally hundreds of gulls staging nearby, and with 21 preceding nest failures over the years — staff deemed it was appropriate to act.

Just not too quickly.

Barber and co-workers in the Game Commission’s Southeast Region office modified a nest exclosure design used in Canada, downsizing it and devising a way to easily carry it to the beach site. It was built in stages around the nest over four days, giving the birds time in between each visit to acclimate to it.

Biologists, meanwhile, monitored the birds daily to make sure they returned to incubate eggs rather than changing their behavior or care of the chicks. Days of nervous waiting followed. Why so nervous? A successful return of nesting common terns would not only be a test of the recovery partnerships working to bring a lost breeding bird back to the state, but also a success that can lead to more terns re-colonizing the site.

That time and patience proved the answer.

In the end, the eggs hatched and the young fledged, something unseen in Pennsylvania common terns since Cassius Clay became Muhammed Ali, the Beatles first came to America and Disney’s “Mary Poppins,” debuted to break box office records.

This is a landmark event in the Game Commission’s mission to conserve and protect a species for present and future generations.

“It’s amazing the things we can achieve when partners work together!” Barber said.