Category Archives: Migration

Hummingbird Day on August 19

Ruby-throated hummingbird, July 2014 (photo by Steve Gosser)

9 August 2023

Have you noticed a lot of ruby-throated hummingbirds at your feeders lately? Their fall migration is already underway so this month is the perfect time to see them up close at Powdermill.

Powdermill Nature Reserve, operated by the Carnegie Museum of Natural History, has one of the longest continually-running bird banding stations in the U.S. Throughout the year they see species abundance ebb and flow based on weather and migration timing.

Ruby-throated hummingbirds (Archilochus colubris) start their fall migration earlier than many other species so they’re more abundant than usual now. Come to Westmoreland County for a family friendly hummingbird event on:

Hummingbird Day, Saturday 19 August 2023, 9:00am-noon at
Powdermill Nature Reserve
1795 Route 381
Rector, PA 15677

Powdermill Nature Center (photo embedded from CMNH Powdermill website)

Learn about hummingbirds, the plants that attract them, and how to care for your feeders so the birds stay healthy. There will also tips on taking great bird photos. And if the weather is good and the birds cooperate we(*) will get to see hummingbirds up close like this one in the bander’s hand. This bird was banded by Bob Mulvihill in Marcy Cunkelman’s garden in July 2015.

(*) I say “we” because I’ll be there, too, to teach you about hummingbirds. I’m looking forward to it!

Ruby-throated hummingbird in bander’s hand, July 2015 (photo by Kate St.John)

This event is free but do register here in advance so Powdermill knows to expect you. As the registration page says:

Events fill up fast! Registration is recommended to guarantee your spot and help us plan timing, seating, and/or trail routes. If there are spots available at the time of the program, non-registered individuals can join on a first-come, first-served basis.

CMNH: Hummingbird Day Event

Click here for more information. Hope to see you there.

(hummingbird photos by Steve Gosser and Kate St. John, Powdermill photo embedded from

Bird News and Pebble Art

Celebrity in Central Park, Flaco the Eurasian eagle-owl, February 2023 (photo from Wikimedia Commons)

28 July 2023

A selection of photos and videos this month around the web:

In February a Eurasian eagle-owl named Flaco escaped from the Central Park Zoo and became a celebrity. He’s still hanging out in July.

In Florida, swallow-tailed kites are preparing to migrate.

In Europe, migration has already begun across the Strait of Gibraltar.

And finally, a pebbly tiger on the beach in Devon, UK by Beach4Art.

(embedded with links, Twitter and Facebook)

One Place, One Time, A Quarter Million Warblers

Bay-breasted warbler (photo by Chuck Tague)

27 May 2023

Imagine spending a day standing on dunes in cold wet weather and seeing a river of a quarter million warblers fly by. This amazing phenomenon was the perfect storm of location, migration and bad weather.

In late May boreal forest warblers such as Cape May, bay-breasted and Tennessee have reached or surpassed Tadoussac, Quebec on the way to their breeding grounds further north. They aren’t nesting yet, so if the weather turns sour they head back south temporarily to wait it out.

Google map showing location of Tadoussac bird count on 24 May 2023 (screenshot from Google maps)

The weather forecast for 24 May looked promising for this perfect storm as Ian Davies (@thebirdsguy) writes in the day’s eBird checklist:
“There were southwest winds overnight (tailwinds good for migration), combined with a big cold front arriving right around dawn, bringing rain, strong northwest winds, and colder temperatures — the same setup that has resulted in flights of tens or hundreds of thousands of birds in past Mays.”

Hoping for a river of warblers, Ian and 11 others headed out to the Tadoussac dunes to count birds. In 11.25 hours they saw 263,771 birds in 96 species! Ian writes:

The first couple hours of daylight featured drizzle and strong winds, and not many birds until about 6:45 … then 500 birds/minute by 7:30. The Tadoussac river of warblers had begun.
This flight continued at 300-500 birds/minute until about 9:20, at which point the rain dropped significantly, and the flood gates opened, as many as 1345 warblers/minute raging past in a torrent of flight calls and glowing songbirds. Birds were everywhere, below eye level, flying between people, pouring through the bushes, landing on the sand, and one Cape May Warbler even tried to land on my arm. A Red-eyed Vireo flew into someone. It was madness. …
For one period of time, the rate of warblers was 80,000/hour.

ebird checklist for 24 May 2023 Tadoussac

Here’s just one of the many videos attached to the checklist. See the checklist for amazing photos, videos and counts.

The location was key to this phenomenon. Tadoussac is located on the northwest coast of the wide St. Lawrence River which funnels birds heading south. If you look at the videos you’ll see that the cameras are pointed toward the St.Lawrence River — east/southeast — and that all the birds are flying southwest.

Satellite Google map showing location of Tadoussac bird count on 24 May 2023 (screenshot from Google maps)

These birds had made it further north but when bad weather arrived they changed direction to escape the storm. Flying on the northwest wind they reached the unsheltered coastal dunes at Tadoussac so they headed southwest to the forest.

What a privilege it must have been to witness a quarter million warblers in just one day.

(maps are screenshots from Google maps; tweet embedded from Ian Davies @thebirdsguy)

Intense Bird Migration Last Night

Scarlet tanager, 2011 (photo by Steve Gosser)
Scarlet tanager (photo by Steve Gosser)

7 May 2023

I haven’t seen a bright red scarlet tanager yet this Spring but I think today’s the day.

Last night from the Rockies to the East Coast nearly a billion birds flew overhead in the continental U.S. According to BirdCast‘s map 886.4 million birds were in the air at 1:00am. The bright white and yellow portions of the map were especially intense.

Bird migration forecast for the night of 6 May 2023 by BirdCast

The birds will land before dawn, perhaps in your neighborhood. I hope some of the prettiest choose Pittsburgh.

Here are a few of the species we’ll see today and in the week ahead in southwestern Pennsylvania. Check the migration forecast at BirdCast every day.

It’s time to get outdoors!

(photos by Steve Gosser, map screenshot from BirdCast)

Look for One Thing, Find Another

American bittern at Panther Hollow Lake, Schenley Park, 28 April 2023 (photo by Charity Kheshgi)

Sunday 30 April 2023

Early Friday morning in pouring rain, Adrian Fenton was at Schenley Park looking for two soras reported the day before on eBird. Soras (Porzana carolina) are unusual in the City of Pittsburgh so it was worth the trip to look for them, but try as he might Adrian could not find any soras. Instead he found something much better.

At 7:29am I was writing Friday’s blog when I got Adrian’s Rare Bird Alert that there was an American bittern (Botaurus lentiginosus) among the reeds at Panther Hollow Lake. This bird is rare indeed! I dropped everything, put on my rain gear, and drove 5 minutes to Schenley Park.

Upon arrival I caught up with Adrian and he showed me where the bittern was. Except that I could not see it at first. Its camouflage is so good that it took me a while to latch onto the bird. Thank you, Adrian, for your patience!

More birders arrived, some looking from above on Panther Hollow Bridge. Charity Kheshgi viewed from eye level, as I had, and captured some great images of this cryptic bird.

American bittern at Panther Hollow Lake, Schenley Park, 28 April 2023 (photo by Charity Kheshgi)
American bittern at Panther Hollow Lake, Schenley Park, 28 April 2023 (photo by Charity Kheshgi)

Charity noticed that the bittern made a vertical wiggle with its neck and took a video. You can hear the sound of red-winged blackbirds and the ka-thunk of cars overhead on the Panther Hollow Bridge in the background. The wiggle is typical American bittern behavior though I’m unable to find an explanation for it.

By the end of Friday, 29 people had reported the bittern in eBird(*) but many more than that stopped by for a look. Some of them missed it on Friday, including Steve Northrop who found a sora that hadn’t been seen all day! See his checklist with sora photo.

So Friday came full circle with a search for a sora that found a bittern and a search for a bittern that found a sora.

On Saturday the bittern and sora were still present with an ever changing crowd of birders, binoculars, cameras and scopes. The crowd did not disturb the birds as the best viewing was from (up the hill) gravel paths 40 feet from the nearest water. The bittern was visible for most of the day Saturday, but the sora remained elusive. Around 6:30pm both birds put in an appearance and Steve Northop was there to witness it. Ta Dah!

Look for one thing, find another.

UPDATE on Friday 5 May 2023: Both the bittern and sora were still present on Friday 5 May in bright sunshine. By that time they’d stayed in Schenley Park more than 7 days and had become celebrities. My estimate is that 200 people came to see them, many of us multiple times.

(photos and video by Charity Kheshgi)

Catbirds Anyone?

Gray catbird (photo from Wikimedia Commons)

20 April 2023

Have you seen your first gray catbird (Dumetella carolinensis) of 2023 yet? I haven’t.

Last week the temperature was so hot for so long in Pittsburgh — up to 16ºF above normal — that we put away our winter coats and wore summer clothes five days in a row. Norway maples burst into full leaf. Oak flowers bloomed. Insects flew around. The ticks came out. (Be careful!) And yet Spring’s migrating birds, the birds we expect under these conditions, did not show up. For instance, where are the catbirds?

As of this writing (6:00am on 20 April) eBird’s gray catbird sightings for April 2023 show that catbirds surround western PA but they aren’t here. Notice the catbird-free zone in western PA.

screenshot map of gray catbird sightings for 1-20 April 2023 (map from Explore Species on eBird)

Zoom in on Allegheny County and you’ll find a single sighting on 8 April in North Park (not shown on map below) and one on 15 April at Riding Meadow Park. Otherwise there are no catbirds in Allegheny County but they’re in the counties around us: Westmoreland, Beaver and Butler. (That red pin drop in the east is in Westmoreland County.)

screenshot map of gray catbird sightings for 1-20 April 2023 (map from Explore Species on eBird)

For some reason Allegheny County, PA is the last place birds want to visit. We have a few theories about it this year but this is an annual problem. Check out the theories and maps in this 2012 article.

p.s. Watch out! More Fire Weather this afternoon!

(photo from Wikimedia Commons, maps from eBird; click on the captions to see the originals)

Bird Populations Are Trending North with Curious Exceptions

Blue jay (photo by Steve Gosser)

19 April 2023

Last November eBird enhanced their Status and Trends website with cool interactive maps of overall abundance, weekly abundance, population trends and range for nearly 700 species. The population trends are fascinating for two reasons: northward movement and curious exceptions.

Many eastern species are moving their breeding ranges northward. For some it’s starkly obvious that they’re declining in the Southeastern U.S. and increasing in the northern U.S. and southern Canada. Click HERE to see 12 good examples at Cottonwood Post.

Blue jay (Cyanocitta cristata) trends are doubly fascinating. Jays are definitely moving north but with a curious exception in south Florida (why increasing there?). Check out their trends map. Blue is good, red is bad.

Blue jay breeding season population trends 2007-2021 (map from eBird Status and Trends)

Most of Pennsylvania has no change in blue jay abundance but did you see the tiny red dot near Pittsburgh? Where is that decline? Drill into the map on the eBird website using these step-by-step screenshots to guide you.

First, click to Explore all Status and Trends Species on eBird. When you get there, click on Search all species at top right.

screenshot from eBird Explore all Status and Trends

I searched for Blue Jay and got a global map. Click on the [Trends] button. Still too tiny! Click on the + sign at top left to zoom in.

screenshot from eBird Explore all Status and Trends: blue jay

As I zoomed in it became apparent that nothing has changed (i.e. white dots) for blue jays in our region until I found that red dot in Cranberry Township. I hovered my cursor over it and found that blue jays declined there 7.5% from 2007 to 2021. I wonder why…

screenshot from eBird Explore all Status and Trends: blue jay

Meanwhile wood thrushes (Hylocichla mustelina) are the curious exception. Though declining overall their trends map doesn’t show the predictable north-south pattern.

Wood thrush singing (photo by Steve Gosser)

Wood thrushes are declining in the Northeast but increasing in the Southern Appalachians and Alabama. A line of “No Change” runs from approximately Kingston, Ontario to Charlottesville, Virginia. Again, I wonder why…

Wood thrush breeding season population trends 2007-2021 (map from eBird Status and Trends)

Try this for yourself at Explore all Status and Trends Species at eBird.

(photos by Steve Gosser, maps from Cornell University eBird Status and Trends)

If You Want To Save Birds, Count Differently

Black-tailed godwit (photo by Andreas Trepte, via Wikimedia Commons)

18 April 2023

Black-tailed godwits (Limosa limosa) are large shorebirds with a worldwide distribution but are listed as Near Threatened because their population declined 25% in only 15 years, 1990-2005. Two thirds of them breed in Europe. In fact almost half the worldwide population breeds in the Netherlands alone.

The European breeders spend the winter in the Mediterranean and Africa including at the Tagus Estuary at Lisbon, Portugal. During spring migration the Tagus hosts up to 40% of all the black-tailed godwits on Earth. Anything that permanently disturbs the Tagus could hurt the godwits.

Black-tailed godwits feeding near Lisbon, Portugal (photo from Wikimedia Commons)

Two decades ago Lisbon, Portugal decided they really need a new airport so they proposed siting it at a former air force base across the Tagus in Montijo.

Proposed airport location at Montijo marked with red X (screenshot from Google maps)

The Montijo Environmental Impact Assessment (EIA) counted black-tailed godwits at feeding and resting sites and calculated how many godwits would be disturbed by the noise of air traffic at 65dB (decibels) (orange outline below, 55dB is the yellow outline). The airport’s EIA said only 0.46–5.5% of the godwits would be disturbed.

Spatial extent of two levels of noise predicted to occur over the Tagus estuary … for 30 sites used by individually tracked godwits between 2000 and 2020. (from “Conservation beyond Boundaries: using animal movement networks in Protected Area assessment” by J. Nightingale et al at ZSL Publications)

Though the EIA used the counting techniques that we use in eBird — the number of birds at rest or in the air at specific points — it doesn’t tell the whole story.

Josh Nightingale, a PhD student with the University of East Anglia and Portugal’s University of Aveiro, decided to study the birds’ flight paths and calculate their larger usage footprint in the Tagus Estuary. The more connections they make, the bigger the footprint.

The size of an impact/protection footprint depends on both the connectivity of impacted sites and the configuration of the entire network. Environmental Impact Assessments typically assume (a) a static population, ignoring connectivity: in such cases the footprint only covers the site(s) directly impacted (red circles). … A network with dense connections, such as (c), will typically result in a greater footprint. …Similarly, an impact on a central site (d) results in a larger footprint. (diagram and caption from “Conservation beyond Boundaries: using animal movement networks in Protected Area assessment” by J. Nightingale et al at ZSL Publications)

Fortunately many black-tailed godwits are banded so Nightingale could use 20 years of location data on 693 banded godwits, many seen twice on the same day in the Tagus area. He then drew connections from site to site to create the godwits’ airspace network. Nightingale also used a 55dB noise plot because that level of noise disrupts 50% of the birds.

Connectivity among sites used across the Tagus estuary. Blue lines indicate connections between sites in the godwit network, representing movements by individual marked godwits within a winter season. (diagram from “Conservation beyond Boundaries: using animal movement networks in Protected Area assessment” by J. Nightingale et al at ZSL Publications)

Nightingale concludes:

Frequent disturbance by aircraft is known to have fitness costs for waders by increasing their energy expenditure, and may cause permanent avoidance of habitat if chronic with long-term consequences for site occupancy. The Tagus godwits’ frequent trans-boundary movements mean that 44.6% of the SPA’s godwit population would be exposed to noise disturbance from the proposed airport, and 68.3% of individuals overall. This compares with estimates of 0.46–5.5% in the airport’s EIA.

“Conservation beyond Boundaries: using animal movement networks in Protected Area assessment” by J. Nightingale et al at ZSL Publications

Nightingale’s paper was published this month in ZSL Publications. Fortunately the Montijo site was placed on the back burner last July. Fingers crossed that this paper tips the balance in the godwits’ favor.

Black-tailed godwit flock in Europe (photo by Keith Gallie via Creative Commons license on Flickr)

In cases like these, if you want to save birds you have to count differently.

p.s. Read more about this study in Anthropocene Magazine: How You Count Birds Affects Airport Design and Permitting. Or this summary in Science Direct.

(photos from Wikimedia Commons and by Keith Gallie via Creative Commons license on Flickr; Lisbon-Montijo map screenshot from Google maps, additional map and diagrams from“Conservation beyond Boundaries: using animal movement networks in Protected Area assessment” by J. Nightingale et al at ZSL Publications. Click on the captions to see the originals)

Seen This Week

Coltsfoot blooming in Schenley Park, 1 April 2023 (photo by Kate St. John)

8 April 2023

This week the temperature stayed above freezing (until this morning) and set a record 85ºF on Wednesday. On a walk in Schenley Park last Saturday 1 April I saw coltsfoot in bloom, Virginia bluebells in bud and flowering Norway maples.

Virginia bluebells about to bloom, Schenley Park, 1 April 2023 (photo by Kate St. John)

By the end of the week the city’s Norway maples had bloomed enough that their profiles looked like green balls instead of stick trees. You’ll can see this on the slope of Mt Washington as viewed from Downtown or the Bluff.

Norway maples flowering, Schenley Park, 1 April 2023 (photo by Kate St. John)

By mid week it was sunny and HOT.

On Wednesday 5 April I visited the Lake Trail at Raccoon Creek State Park to find newly arrived Louisiana waterthrushes (). Near one of the singing birds was a puddle of trilling and mating American toads. I recorded their sound and added a my (lousy) photo of mating toads + a Wikimedia photo of the Louisiana waterthrush when he sings in the recording. You can also hear the wind on the mic.

video by Kate StJohn Birdblog on YouTube

Also at Raccoon: spring beauty () and yellow corydalis (). I wish I could have stayed longer.

Spring beauty, Raccoon Creek State Park, Lake Trail, 5 April 2023 (photo by Kate St. John)
Yellow corydalis, Raccoon Creek State Park Lake Trail, 5 April 2023 (photo by Kate St. John)

Remember the yellow buckeyes in Schenley Park from last week? Here’s what they looked like yesterday!

Yellow buckeye leafout progress, Schenley Park, 7 April 2023 (photo by Kate St. John)

More Spring to come.

(photos and video by Kate St. John)

Waiting For Hummingbirds

Male ruby-throated hummingbird (photo from Wikimedia Commons)

4 April 2023

Though the next two days will feel like summer in Pittsburgh with highs of 72ºF and 82ºF, the hummingbirds will not be back yet. Where are they now? When will they get here?

Our only hummingbird, the ruby-throated (Archilochus colubris), has a wide breeding range in eastern North America and a narrow wintering range in Central America and the southern tip of Florida.

Thanks to Hummingbird Central’s spring migration map, we can see that a few daring individuals flew north inside Florida in February but most migrants showed up in Central/North Florida and on the Gulf Coast in early March. By now, 4 April, the leading edge of hummingbird migrants has covered central and coastal North Carolina and has a foothold in southeastern Virginia.

Today’s snapshot shows the gap between Pittsburgh and the leading edge of hummingbirds.

Ruby-throated hummingbird migration progress as of 4 April 2023 (screenshot of map from

Will they reach Pittsburgh this month? Yes, one or two brave ones, but I predict the big push won’t get here until early May. My eBird sightings of ruby-throated hummingbirds in Frick/Schenley Parks consistently shows first arrivals on May 2-4 for the past five years.

  • 13 May 2012
  • … gap of 6 years …
  • 4 May 2018
  • 4 May 2019
  • 3 May 2020
  • 3 May 2021
  • 2 May 2022

(Go ahead, hummingbirds. Prove me wrong and arrive early!)

Watch the progress of hummingbird migration across North America at Hummingbird Central’s 2023 Spring Migration Map.

Be prepared to be jealous of locations north of us where hummingbirds have already arrived. Here’s why that happens:

(photo and range map from Wikimedia Commons; spring migration map screenshot from Hummingbird Central)