Category Archives: Migration

Elusive Celebrity Warbler Visits Pittsburgh

Connecticut warbler at Bellevue Memorial Park, 24 May 2025 (photo by Steve Gosser)

25 May 2025

On 18 May Chris Lituma reported a Connecticut warbler (Oporornis agilis) at Bellevue Memorial Park. By the end of the week Steve Gosser and I were two of about 100 people who looked for the bird. Many of us went twice. I did.

So a Connecticut Warbler has been hanging at Bellevue Park for nearly a week now. Not only are these warblers not common but they are true skulkers that usually stay hidden. I went over a few nights ago and got to hear him sing but no luck with photos. This evening I went back over and I finally got him after waiting nearly 2 hours for him to pop up. Looking back at my archives, the last one I saw and got pics was back in Sept 2016, nearly 9 years ago! Yes this is a very special bird and so thrilled I got some photos.

Steve Gosser on Facebook, 24 May 2025

A hundred Pittsburgh birders showed up for this warbler because he is rare and very hard to find. Crowd sizes varied. This is the midday crowd on Friday.

Birders looking for the Connecticut warbler at Bellevue Memorial Park, 24 May 2025 (photo by Charity Kheshgi)

Why so many people and why did we come more than once?

Connecticut warblers are skulkers that slowly poke around out of sight in the underbrush and thickets. The male’s song is quite loud and he throws his head back when he sings so the sound bounces off the low canopy.

He’s impossible to find if he’s not singing so if you showed up at 1:00pm on Wednesday, as I did, and the bird is silent and you only have half an hour to wait for him to sing. … Well you’ll have to come back later.

When I returned on Thursday he was singing but it still took an hour to see him. First looks are usually poor but rewarding. Charity Kheshgi visited several times to get a good photograph. Notice how the views improved.

My best view was this one, captured by Ryder Shelley who was standing next to me on Thursday.

And this view is why everyone comes back, over and over again. It takes a lot of luck to see a Connecticut warbler this well. Phillip Rogers was very, very lucky.

As of 7:50am today (25 May) the warbler is still in Bellevue Memorial Park. Someone heard him this morning and is hoping to see him.

Sooner or later the bird will leave for his breeding grounds up north but we won’t know he’s gone until people try for at least a day with no luck.

UPDATE on Tuesday 27 May 2025: The Connecticut warbler is gone. No one has reported it since the afternoon / evening of Sunday 25 May.

Unexpected Item on Pitt Peregrines’ Menu

Male chick from Pitt peregrine nest on Banding Day, 21 May 2025 (photo by Kate St. John)

24 May 2025

On Thursday I wrote about the Pitt peregrine banding on 21 May — see story & photos here — but I did not include a photo of the unusual prey item Patti Barber found at the nest. It was the skull of an American woodcock (Scolopax minor), a “timberdoodle.”

I have never seen a woodcock in the city and certainly not in Schenley, the nearest park to Pitt’s campus. Schenley’s habitat is not suitable for woodcocks but they do court, and therefore breed, at North Park’s Upper Field.

American woodcock among fallen leaves (photo from Wikimedia Commons)

In spring and fall American woodcocks migrate at night, passing over the City of Pittsburgh on their way.

I imagine this one was flying above the Cathedral of Learning one night when the peregrines saw it lit by the building lights and flew up to get it. Yes, peregrines do hunt at night if there’s abundant prey and enough light to see it.

Prey item from Pitt peregrine nest: American woodcock collected on Banding Day 21 May 2025 (photo by Kate St. John)

At study published in 2006 documented peregrines hunting at night at the Empire State Building and in 2019 Jeffrey Ward took a video of one hunting in the 911 Tribute Lights in New York City. See the details at the links below:

So what about this unexpected prey item?

The Cathedral of Learning is lit on the nights after sports victories by Victory Lights similar to the 911 Tribute Lights. In October 2018 I wrote about the Victory Lights’ deadly attraction for migrating birds and within two weeks Pitt had a plan to cycle the lights every hour to break to spell they cast on migrating birds.

If this woodcock was attracted to the Victory lights the lights would have cycled and released him within the hour. But with three hungry mouths to feed, the peregrines didn’t wait that long. 🙂

First Monarch Butterflies Have Arrived in PA

Male monarch butterfly, 2008 (photo by Marcy Cunkelman)

14 May 2025

Monarch butterflies (Danaus plexippus) are migrating north and, happily, the first few have arrived in Pennsylvania within the past two weeks.

As of this morning there are 11 monarch butterfly sightings on Journey North’s 2025 spring migration map. Here are six of the 11 including the very first one on 30 April in Philadelphia.

  • Philadelphia, Philadelphia County, 4/30/2025
  • Pittsburgh, Allegheny County, 5/5/2025
  • McKees Rocks, Allegheny County, 5/10/2025
  • Pennsylvania Furnace, Centre County, 5/10/2025
  • Gettysburg, Adams County, 5/11/2025
  • York, York County, 5/12/2025

These sightings were gleaned from the Journey North Monarch (Adult) First Sighting map, shown below in a screenshot frozen in time on 14 May 2025.

screenshot of Journey North Monarch (Adult) First Sighting map as of 14 May 2025

Ideally we’ll see a handful more monarchs this year compared to last because …

In March the World Wildlife Fund reported that December 2024’s count of eastern monarch butterflies wintering in Mexico showed the eastern population had nearly doubled since the prior year. This is good news in the very short term but is tempered by a sober look at World Wildlife Fund’s Annual Count graph, embedded below. (Purposely small so that you click here to see the full size graph at WWF.)

The graph shows healthy large populations from 1993-1994 through 2003-2004, then acreage drops off to the worst year of only 1.66 acres (in red) in 2013-2014.

This year’s 4.42 acres (2024-2025) is nearly twice last year’s 2.22 but both are still among the five lowest levels in 32 years. There’s a lot of work to do both here and in Mexico to continue the monarchs’ turnaround. (*)

Meanwhile, watch monarch butterfly migration at the Journey North 2025 monarch map. Click the Play button on the map’s control panel (screenshot below) to see their progress.

Report the ones you see to put them on the map.

(*)For information on the monarchs’ plight see July 2024’s blog: Have You Seen Any Monarchs This Year? and Christine Rickabaugh’s comment about the situation in Mexico.)

Three Days in Ohio Before The Biggest Week

Prothonotary warbler at Magee Marsh Boardwalk, May 2014 (photo by Chuck Tague)

6 May 2025

Today I’m driving to Northwest Ohio to get my annual warbler fix at Magee Marsh Boardwalk. I’ll be there three days before The Biggest Week in American Birding on 9-18 May 2025 to avoid the crowds.

screenshot from 2025’s Biggest Week in American Birding homepage

There are quite a few birds I’ve missed so far in Pittsburgh that I hope to see in Ohio including prothonotary warbler and magnolia warbler pictured here. Last year my pre-Biggest-Week trip was too early for peak migration but this year my timing may be perfect. Peak migration is 7-25 May in northwestern Ohio.

To give you a taste of how close the birds are at Magee Marsh Boardwalk, here’s a 2016 video by Sarah Winnicki with super looks. Give yourself a warbler quiz by identifying them in the video.

video embedded from SK Winnicki on YouTube

Speaking of Biggest Week crowds: It will be interesting to find out if the crowds reach the predicted 80,000 – 90,000 without the usual influx of Canadians. By the end of March, Cleveland had already noticed a 30% drop in Canadian visits to the Rock & Roll Hall of Fame.

For cities like Cleveland that rely on tourism dollars from diverse sources, including Canadian visitors arriving via Great Lakes cruise ships, the emerging trend presents a significant challenge. As Johnston noted, “we’re going to keep seeing the fallout of this” if political tensions continue to escalate.

Cleveland.com: Our neighbors are angry: tourism takes political turn as Rock Hall sees 30% drop in Canadian Visitors

Huge Migration Last Night!

29 April 2025

BirdCast predicted intense migration over much of the U.S. last night and indeed it was.

screenshot of Birdcast migration forecast map for the night 28 April 2025

Here in Pittsburgh they estimated that 3,080,900! birds passed over Allegheny County overnight.

It was the highest migration count so far this year and far exceeded the historical average, even during peak migration in May. The red arrow on the screenshot below of Allegheny County’s Migration Dashboard shows that the birds were numerous and early. Click here for the most up-to-date Allegheny County, PA Migration Dashboard.

screenshot from BirdCast’s Allegheny County, PA Migration Dashboard on the morning of 29 April 2025

Expect to find the birds pictured in the slideshow above and much, much more. How many of those birds landed here this morning?

It’s time to get outdoors!

Meanwhile be sure to visit BirdCast for future migration predictions and seasonal statistics for your area.

When Will New Birds Get Here?

Yellow-throated warbler (photo by Steve Gosser)
Yellow-throated warbler (photo by Steve Gosser)

14 April 2025

Last weekend in Pittsburgh we were reminded that migration really is heating up when at least five rare water birds were present in Allegheny County and Moraine State Park. Birders chased for a glimpse of the barnacle goose (who was on the move yesterday and may have left last night), a flock of red-necked loons in non-breeding plumage, a single red-necked grebe, an arctic tern, and a small flock of American white pelicans on Lake Arthur. There may have been others. The alerts were intense.

And now there’s a selection of early warblers in the area: Louisiana waterthrush, pine, yellow-throated and yellow-rumped warblers.

Now’s the time to start checking birdCast.info to help you find the birds. The tools include:

This morning’s Migration Dashboard for Allegheny County shows that last night was the most intense night so far this spring. We’d been seeing low migration for 12 days, then last night almost a million birds passed overhead. Reality Check: Lots of birds passing overhead often means they didn’t stop here. 🙁

There is also a new tool that tells you the Peak Spring Bird Migration Periods for 1,000 U.S. Cities. This small-size map, embedded from that report, is just a tease for the details you’ll find when you scroll down at this link.

For example, on average peak migration in Pittsburgh is May 7-22.

One more tease: Here’s what we’re looking for.

  • Hooded warbler (photo by Steve Gosser)

Warblers in southwestern PA in early May (photos by Steve Gosser)

Rare in Time But Not Place

Northern rough-winged swallow on a wire (photo by Chuck Tague)

1 April 2025

On Sunday I saw two rare birds: the barnacle goose (Branta leucopsis) at Creighton and a northern rough-winged swallow (Stelgidopteryx serripennis) at Duck Hollow. The barnacle goose is obviously rare — far outside its range and none had ever been reported in Allegheny County — but northern rough-winged swallows are returning on migration yet eBird made me justify it.

The two birds represent different kinds of “rare.” The goose is rare in place no matter what time of year. The swallow was rare in time though it was in the right place. I reported the swallow on 30 March but he wasn’t supposed to arrive last month. Today, 1 April, eBird says that northern rough-winged swallows are not rare at all.

As spring migration heats up we’ll encounter more birds rare in time as the early individuals arrive ahead of the crowd. Here are a few species we expect to see this month … but not yet.

Rare in Pittsburgh on 1 April but OK in late April:
Blue-headed vireo, late April 2021 (photo by Steve Gosser)
Adult male purple martin (photo from Wikimedia Commons)
Blue-gray gnatcatcher, 24 April 2020 (photo by Steve Gosser)
House wren (photo by Chuck Tague)
Gray catbird (photo by Shawn Collins)

Something to look forward to!

Population Hit by Bird Flu Recovered in Just 2 Years

Barnacle goose closeup (photo from Wikimedia Commons)

9 March 2025

Every autumn barnacle geese (Branta leucopsis) leave their arctic breeding grounds and migrate to Europe. In 2021-2022, those wintering at Solway Firth, UK(*) became infected with highly pathogenic avian influenza (HPAI) H5N1 and 31% of them died. Even though their population had been devastated, they recovered to full strength in just two years. This can give us hope for North American birds hit hard by bird flu.

Wild barnacle geese breed in Greenland, Svalbard and Siberia yet each population has its favorite wintering site as shown on the map. Counts on the wintering grounds are directly tied to one breeding location.

Distribution of barnacle geese highlighting the studied population in 2021-22 (map from Wikimedia Commons)

The winter population at Solway Firth breeds at Svalbard.

Wintering flock of barnacle geese in the fog at Solway Firth (photo from Wikimedia Commons)

When bird flu hit Solway Firth in the winter of 2021-2022 researchers began a two+ year study to measure the demographic impact of the major HPAI outbreak on barnacle geese. During the outbreak they carefully counted dead goose carcasses and, thanks to fencing, were able to extrapolate for predation.

By February 2022 the barnacle goose population had dipped precipitously, but in the two years that followed the number of juveniles increased even faster. High birth rates on the breeding grounds quickly made up for the loss of adults.

Year to year maximum late-winter count of barnacle geese at Solway Firth. From Impacts of highly pathogenic avian influenza (HPAI) on a Barnacle Goose Branta leucopsis population wintering on the Solway Firth, UK

Researchers speculated that …

The large impact of HPAI-related mortality on the Solway Barnacle Goose population was rapidly recovered, probably through a combination of the widespread development of natural immunity and high levels of breeding success in the years following the outbreak.

Impacts of highly pathogenic avian influenza (HPAI) on a Barnacle Goose Branta leucopsis population wintering on the Solway Firth, UK

In Pennsylvania, snow geese have been hard hit with wild bird flu. It will be interesting to watch how their winter population fluctuates in the eastern U.S. in the years ahead.

p.s. We don’t have barnacle geese in the U.S. Here’s look like.

Barnacle geese (center of photo) look unique but are similar in size to their nearest relative the cackling goose.

One barnacle goose with many cackling geese (photo from Wikimedia Commons)

Size comparison! Though cackling geese look like Canada geese they are much smaller. Thus barnacle geese are smaller than Canada geese we see in Pittsburgh.

Two cackling geese with a Canada goose (photo from Wikimedia Commons)

(*) Solway Firth forms the western border of Scotland and England.

Falconcam Crew Finds a Cache of Cuckoos

Pileated woodpecker skull from Pitt peregrine cache area, 10 Jan 2025 (photo by Kate St. John)

11 January 2025

Yesterday the Univ of Pittsburgh, the National Aviary, and I prepared for the upcoming peregrine nesting season by cleaning the nestbox and falconcams.

After examining the indoor side of the camera equipment Bob Mulvihill of the National Aviary and Gracie Jane Gollinger from Pitt IT braved 10°F weather on the ledge. Camera cleaning went well despite the cold weather and there was nothing to clean at the nestbox. However …

Bob Mulvihill and Gracie Jane Gollinger traverse the ledge, 10 Jan 2025 (photo by Kate St. John)
Bob Mulvihill cleans the snapshot camera, 10 Jan 2025 (photo by Gracie Jane Gollinger)

When Bob stepped out on the landing that leads to the cameras, we were amazed that the area at his feet was strewn with partially eaten prey. I kept a list. Some were hard to identify.

  • Rock Pigeon (Feral) 1
  • Yellow-billed Cuckoo 3 or 4
  • Black-billed Cuckoo 1
  • Pileated Woodpecker 1
  • Northern Flicker 1 (yellow feathers)
  • European Starling 1
  • Wood Thrush 2 or 3

Up to 5 cuckoos! The landing was clean when the chicks were banded on 21 May 2024 so the cache was left since then.

Bob stands among dehydrated peregrine prey: 2 yellow-billed cuckoos and a northern flicker (photo by Kate St. John)
More peregrine prey on the landing, 10 Jan 2025 (photo by Kate St. John)

The most interesting find was the skull of a pileated woodpecker. I assumed that peregrines would never capture a bird with such a dangerous beak but I was wrong.

Pileated woodpecker skull from Pitt peregrine cache area, handheld for scale, 10 Jan 2025 (photo by Kate St. John)
Female pileated woodpecker skull from peregrine cache area, found 10 Jan 2025 (photo by Kate St. John)

Why so many prey items at this spot? Perhaps it was a favorite dining area where the adults dropped off food for last year’s youngsters.

Why so many cuckoos? The Pitt peregrines have always had a fondness for cuckoos, probably because their flight is floppy which makes them easy to catch. My only regret is that the peregrines caught so many cuckoos and wood thrushes.

Here’s the crew after our successful visit.

Left to right: Dante Bongiorni (Pitt Facilities Mgmt), Bob Mulvihill (National Aviary), Doug Cunzolo (Bob assist), Gracie Jane Gollinger (with hat, Pitt IT), Megan Hinds (National Aviary), Kate St. John (“The Peregrine Lady”) — photo by Gracie Jane Gollinger

We’re ready for Peregrine Season!

Just a Few Rare Geese

Greater white-fronted geese (photo from Wikimedia Commons)

23 December 2024

It seems that Pittsburgh missed waterfowl migration this fall with only a handful of the expected migrants landing on our rivers and lakes. Except for long distance migrants, waterfowl haven’t come at all.

Some ducks, geese and gulls only move south when ice overtakes their location. If they’re hanging out at Lake Erie near Presque Isle, the map of yesterday’s water temperature indicates they have no reason to leave. The water there is more than 40°F and the only ice is in small bays (black color on the map).

Great Lakes surface Temperature and ice cover as of 22 Dec 2024 (map from Great Lakes Environmental Research Lab)

There are a few rare geese, though, photographed and posted to eBird and embedded below.

There’s currently a Ross’s goose (Anser rossii) at North Park, noticeably small than the Canada geese it’s hanging out with.

Yesterday there was a brant (Branta bernicla) at Duck Hollow without any Canada geese to keep it company. So it hung out with ring-billed gulls.

And a flock of 16 greater white-fronted geese (Anser albifrons) who normally migrate west of the Mississippi and winter in Louisiana, southern Texas and Mexico have been hanging out with Canada geese in Butler County since 1 December.

These geese are called “white-fronted” because their foreheads are white.

Wondering why the ducks aren’t here? This 2021 vintage article explains why.