This story is part of our series, Wild Pennsylvania. Check out all of the other stories in the series here.
Something happened this summer at Presque Isle State Park on Lake Erie that hasn’t happened in over 60 years: two young common terns, endangered in Pennsylvania, fledged from their nest.
The juvenile terns (Sterna hirundo), which look like small seagulls, flew from their protected nest on the sandy beach in the park’s Gull Point area on August 17. Mary Birdsong was there to watch it happen on a nearby observation platform.
“I was kind of jumping up and down,” she said.
Birdsong (yes, that’s her real name) is the assistant director of the Erie Bird Observatory and its lead shorebird monitor. She spoke with The Allegheny Front’s Kara Holsopple.
LISTEN to the interview
Kara Holsopple: What do common terns look like?
Mary Birdsong: For the average listener, they kind of look like gulls. They’re a little bit smaller. They’re white and gray. They have a black cap on their head in the breeding season and an orange beak with a black tip and black legs.
Kara Holsopple: And what kind of sound do they make? Is it like a gull?
Mary Birdsong: Well, no, they call it a keer call. It’s a harsh keer call, and it’s repeated over and over again.
Kara Holsopple: What kind of habitat do common terns like, and how has Presque Isle become a good breeding ground for them again?
Mary Birdsong: For breeding, they prefer a habitat that’s a sandy substrate with no trees, and they’re ground nesters, so they like a little driftwood and rocks nearby so that they can kind of camouflage their nest within it. They build a little cup in the sand, and that’s where they lay their eggs. And the habitat at Gull Point is the only place in the state appropriate for common tern nesting.
Any time a state can make one little success towards taking a bird off an endangered list is a milestone that we all need to celebrate.
Kara Holsopple: Is Gull Point a place where other shorebirds have nested over the years?
Mary Birdsong: Annually, we have killdeer and spotted sandpiper that nest there, and also the very famous and highly endangered piping plover that has nested there since 2017.
Kara Holsopple: The nesting history of common terns at Gull Point has been a bit up and down. When was the species first recorded there?
Mary Birdsong: Back in 1904. They were recognized by a man named Clyde Todd, who wrote a book, “Birds of Western Pennsylvania,” in 1940. He said they were nesting there in 1904. That’s the earliest recorded modern record that we have. By the 1920s, there was a small colony there, and by the ’30s, there was a very large colony of at least 125 nests that spread for a quarter of a mile.
Kara Holsopple: When did the birds stop nesting in that area?
Mary Birdsong: The last known nesting there was in the 1960s. We don’t know if they fledged, but they were attempting to nest. Recreational use by humans is one of the primary causes of them not being able to nest at Gull Point anymore because a lot of people would tie up their boats there and enjoy the beach. Ground nesters can’t handle people running around where they nest. They’re going to abandon it.
Kara Holsopple: At some point, Gull Point was closed, right?
Mary Birdsong: Yes, in 1993, the point was closed by the park as a natural area. There’s still a trail that goes out there where you can walk to two observation platforms, but the rest of the area is closed, which gives the birds the solitude and the lack of disturbance that they need.
We had an eight-nest colony in 2015, but none of those birds successfully fledged. They were either washed out by the lake during a storm or they were taken by predators. In 2022, we had a nest, and for the first time, we had a hatch. But they were gone very quickly. They were eaten by something.
Kara Holsopple: The Pennsylvania Game Commission gave these two juvenile common terns that we’re talking about today a little help with an enclosure around the nesting area. How does that work, and what were the risks of interceding like that?
Mary Birdsong: Well, this pair had nested earlier in the year, and they did reach hatch. But again, the chicks disappeared, and the Game Commission decided that they were going to try and attempt again because they figured the risk was worth it. So they modified an exclosure. It’s actually called an exclosure, that was developed by Presqu’ile Provincial Park in Ontario, and they just sized it down to surround one nest.
It had solid sides with a mesh above it, and then they had string over the top of it. The adult terns could come and go through those strings, although they struggled with that a little bit, depending on which way the wind was blowing and how strong it was blowing. The chicks were safe in that closure until they were ready to fly, and eventually, they made their way out of it.
The Pennsylvania Game Commission made an “exclosure” to protect the common tern eggs from predators. Photo: Mary Birdsong
Kara Holsopple: How will you know what happens to them next? Will you know if they return?
Mary Birdsong: We will never know. The pair that has been trying to nest there, we kind of assume it’s the same pair, but we’re not absolutely sure. These birds don’t get banded, so we don’t have any idea. They’re going to look like every other common tern on the beach, and we won’t be able to distinguish them from any others.
Kara Holsopple: So what does this event mean for the future of nesting terms on Presque Isle?
Mary Birdsong: Well, we don’t know. It was one tiny little step, a goal of having them nest in a colony there regularly. But there are no guarantees. Just like with piping plovers, there’s no guarantee that they’re going to come back and nest again. Nature is a harsh place, and we never know what we’re going to have each year.
Kara Holsopple: Having success at a breeding site would make them more likely to return, right? And piping plovers have returned over the years since 2017.
Mary Birdsong: Yes. And some of them have been the same birds and some of them have been other birds. We can actually track those because they do get banded and unique color bands so we can identify them to individuals.
Kara Holsopple: I don’t know if this is the right thing to say, but congratulations.
Mary Birdsong: Thank you. We’re very, very happy and we’re very happy to share the news with everyone. You know, any time a state can make one little success towards taking a bird off an endangered list is a milestone that we all need to celebrate.
Mary Birdsong is the assistant director of the Erie Bird Observatory and its lead shorebird monitor. She wrote about the fledging of common terns on Presque Isle for Erie Reader. She was also a contributor to The Allegheny Front’s Bird Files series.
