Extremely rare birds visit Pennsylvania this summer

Two birds captured a lot of attention during the past few weeks. A white-winged tern — which sometimes goes a whole year without being spotted in the U.S. — spent four days in Tiago County, and a roseate spoonbill thrilled birders in Cumberland County for four weeks.

Thursday was Rich Hanlon’s day off, so he set out to see what birds might be around a few local lakes. His first stop was Lake Nessmuk, just a short distance from his home in Wellsboro, Tioga County. He stopped about 40 yards short of the water’s edge when he noticed an unusual dark-colored bird perched on a post. He checked it out with his binoculars — it had some gray on its face — and he thought it might be a molting black tern.

“Believing I was in the presence of a rare migrating black tern, I called my birding friends, Kathy Riley and John Corcoran, both active in the Tiadaghton Audubon Society,” Hanlon said.

Riley and Corcoran arrived 10 minutes later — about 11:45 a.m. — and the trio used their binoculars, camera, spotting scope and a field guide to rule out the rare black tern. Instead, they suspected that they could be looking at a super rare white-winged tern.

The white-winged tern is a Eurasian species that visits the United States very infrequently. According to my Sibley field guide, it is unusual to have even one reported sighting in the U.S. each year. Unlike the common or Forster’s terns that one might see on the Atlantic Coast, the white-winged tern never plunge-dives. It feeds on the wing by catching large insects in the air or skimming small fish from the surface of the water.

“We got the word out quickly, and within a few hours, crowds were beginning to form at the lakeshore,” Hanlon said. “It was mostly locals at first, but then people from all over Pennsylvania and New York were there by evening on that first day — Aug. 10.”

At 5 p.m., a team arrived from the Cornell Lab of Ornithology in Ithaca, N.Y. They verified the identification made by the three local birders. It was a rare white-winged tern — so extraordinary, that it was the first sighting in the United States this year and the first-ever reported in Pennsylvania.

“I was told by the Cornell crew that one of the reasons the tern decided to settle at Nessmuk was because the habitat is very good for it,” Hanlon said.

In Europe, white-winged terns prefer unpolluted, shallow marsh habitats that have good perches close to the water’s surface. Nessmuk Lake is a small, shallow Fish and Boat Commission-owned impoundment, with post clusters sticking out of the water and downed tree tops to provide perches for the tern. At 60 acres, Nessmuk is just a bit smaller than Centre County’s Colyer Lake.

When I arrived at the lake the following evening, 10 birders were standing in the rain observing the tern. Once the rain stopped, the crowd size quickly doubled — including a photographer from Pittsburgh and birders from New Hampshire and Massachusetts.

Cameras would really click when the tern left its perch to feed. However, resident barn swallows — who seemed to resent the competition for food — harassed it each time. According to Hanlon, the swallows would roost just before dark, allowing the tern to feed in peace.

“My favorite experiences with the white-winged tern were in the evenings, just before dark, when it would go into a feeding frenzy, making pass after pass over the shallow marsh at the south end of the lake,” Hanlon said. “The chimney swifts especially seemed to welcome the white-winged tern, and there were moments when the tern would assimilate with their flock, moving in unison with the swifts through areas of densest insect activity.”

It was a good find for Hanlon, the pastor of the United Methodist Church in Wellsboro. According to the Tiadaghton Audubon Chapter, about 300 people came to Wellsboro to see the rare bird over those four days — some from as far away as Florida, Texas and Colorado. Many frequented local restaurants and hotels, making a welcome economic impact on a small community.

Another rare-for-Pennsylvania bird, the roseate spoonbill, caused a recent stir when it was spotted along Conodoguinet Creek in Cumberland County.

The roseate spoonbill normally lives in Florida, Louisiana and Texas. Why one or two have been found 1,000 miles north in Pennsylvania is anyone’s guess, but even more intriguing is why it traveled all that distance and then remained in the same 300-yard section of Conodoguinet Creek for nearly a month.

The aptly-named spoonbill has an elongated beak that is flattened and rounded at the end. Their specialized bill is used to sift sand and mud to locate food. The roseate spoonbill stands nearly a yard tall. Like flamingos, spoonbills get their pink feather coloration from the food that they eat.

Cornell University’s eBird website collects and organizes bird sightings from all over the world. Nearly 150 people have posted eBird sightings of the Cumberland County spoonbill. More than 50 of those eBird reports occurred the weekend of July 22-23 alone. Many other birders where there but did not use eBird.

Why did the spoonbill attract hundreds of birders? It has been nearly 50 years since the last roseate spoonbill was spotted in the Keystone State. This year’s sightings are only the fourth time a spoonbill has visited the state — ever. The last sighting occurred in 1968 in Erie County.

As if the birding world experienced some kind of synchronicity, both rare birds were last seen on Aug. 13. I wonder when the next unusual species will pop up. You can be sure that Pennsylvania birders will be watching.

This story was originally published August 19, 2017 at 11:29 PM with the headline "Extremely rare birds visit Pennsylvania this summer."