14 September 2023

Pittsburgh’s bird migration forecast looks great for three days in a row. Last night through Friday night will see a huge passage of birds overhead with excellent birding opportunities today, Friday and Saturday.

Here’s what migration radar looked like at 5:00am this morning.

During this massive movement some species are departing, some arriving. Let’s take a look again at Birdcast’s regional list of Species On The Move, described in detail last month, to learn what we can expect to see.

Noticable Departures: Who Just Left?

Lots of species left recently but most of them were shorebirds. Since Pittsburgh doesn’t have a shore we rarely see those listed below. Occasionally a lesser or greater yellowlegs is reported but don’t expect to find one now.

Here’s a quick summary of rapid departures as of 14 September 2023 in a screenshot from BirdCast. Note that cedar waxwings are here right now but will rapidly depart around 27 September. Yellow-billed cuckoos on the list because I always hope.

Peak Influx: What will we see this week? Warblers!

For the Upper Midwest and Northeast region, 13 to 17 September is the peak of warbler migration.

I’ve featured the ovenbird because yesterday (last night!) was its peak influx point. No surprise then that Nick Liadis banded one yesterday at Hays Woods during Linda Roth’s 40 Acres a.k.a. Hays Woods Enthusiasts live stream. Check it out here.

And if you thought you’d seen a lot of magnolia warblers already, the next few days will be exceptional. They reach their regional peak influx on Sunday.

Here’s a screenshot of the Noticeable Peak Influx as of 14 September 2023. Note the exclamation point next to magnolia warbler in the chart below!

With so many birds on the move, now’s the time to get outdoors. Be sure to check BirdCast for the latest forecast.

(photos from Steve Gosser, Lauri Shaffer, Kate St. John. Tables are modified screenshots from BirdCast’s Species On The Move for the Upper Midwest and Northeast. Be sure to check BirdCast for the latest data)

29 August 2023

Olive-sided flycatchers (Contopus cooperi) are rare birds in Pittsburgh. Not only have they declined 78% since 1970, but they are only present on migration and then just one or two per season. When three individuals were found on the same day, Friday 25 August, in Allegheny County it was rare indeed. These three were not the same bird:

• Sewickley Heights Borough Park at 8:20am, seen recently on Monday 28 Aug
• Hartwood Acres, Saxonburg Fields at 10:50am
• Homewood Cemetery at noon

Though olive-sided flycatchers nest from Alaska to Newfoundland and southward into the Cascades and Rockies, not much is known of their migration routes. In the fall the eastern birds generally flow westward within Canada, then hang a left at Minnesota and migrate through the Great Plains and eastern Rockies. You can see their relative abundance from the 3rd week of August through the 3rd week of October in this slide show.

Olive-sided flycatcher weekly relative abundance from eBird Status and Trends

Alaska’s breeding olive-sided flycatchers are declining rapidly and have one of the longest migrations of any flycatcher — from Alaska to Peru. Migratory stopover sites are very important for their survival but nobody knew where they went so a study team, headed by Julie C. Hagelin, decided to track the birds’ migration by catching them in mist nets and attaching geolocator backpacks.

What they discovered when the birds returned is that Alaskan breeders fan out across the Rockies on their way south, some as far east as Texas, before they head through Mexico to South America. They also found 13 important stopover sites that are critical to the birds’ survival on migration. Their favorite spots are slightly different in Central America in fall versus spring. Two of the 13 sites are in the U.S. Cascade Mountains. All the sites are on these maps.

Pittsburgh never figures heavily in the olive-sided flycatcher’s travel agenda though this year we seemed to be an attractive stopover. Our birds probably come from breeding sites in eastern Canada.

Are our olive-sided flycatchers stopping at the same places in Central America as the Alaskan group? We won’t know until some runs a similar study in eastern Canada.

(photo from Wikimedia Commons, abundance maps from eBird, stopover maps from DeGruyter; origin links are in the captions)

19 August 2023

Fall migration is underway across the Northern Hemisphere. Some birds migrate alone or in small flocks that don’t attract much attention. Others gather in such massive flocks that they are hard to miss.

At pinch points along their migration routes from Europe to Africa, white storks (Ciconia ciconia) travel in very large flocks like the kettles of broad-winged hawks in North America. Two such pinch points are in the airspace over Israel, above, and at the Strait of Gibraltar.

In this short video white storks are about to cross the Straits from Spain to Morocco but hit a wall in the air — the levant wind blowing from the east — so they wheel back. They did not leave Spain that day.

1,640 White #Storks attempting to cross The #Straits this morning ! The #levante wind forcing them to break rank and head back ! ….maybe tomorrow. #FlywayBirding #Tarifa #Facinas #Birding #Migration #VisMig pic.twitter.com/TUcgIc3Rth

— Inglorious Bustards (@Otis_inglorius) August 9, 2023

In North America semipalmated sandpipers (Calidris pusilla) migrate in massive numbers from their breeding grounds in the Arctic to the shores of South America.

At the Bay of Fundy the flocks can number in the hundreds of thousands in August and early September.

One highlight on our @EagleEyeTours trip to New Brunswick is a visit to Johnson Mills Shorebird Reserve. Besides the incredible Bay of Fundy tides, we witnessed the spectacle of 65+ THOUSAND Semipalmated Sandpipers roosting, flocking and doing synchronized aerial acrobatics. pic.twitter.com/6aqAJUtt9p

— Jared Clarke (@birdtherock) August 18, 2023

(photos from Wikimedia Commons; tweets embedded)

14 August 2023

A lot of us think that fall migration doesn’t start until the end of August, but guess what? BirdCast resumed migration predictions on 1 August and their regional lists of Species On The Move show an influx of 10 noticeable species this week while five have already left, or are about to. Don’t wait to go birding. Check BirdCast tools to find out why.

Species On The Move uses two decades of eBird data to calculate movement from start to finish within four regions: Upper Midwest & Northeast, Gulf Coast & Southeast, Great Plains, and West. Of course they list First Arrival, Peak, and Last Departure but my favorite markers are:

• Noticeability: *** Three asterisks mean we’re really likely to notice this species.
• Rapid Migrant Influx: A few may be here already but numbers increase rapidly on this date.
• Rapid Departure: Numbers drop quickly on this date though a few will linger.

The tables are grouped by region with Pittsburgh in the heart of BirdCast’s Upper Midwest & Northeast region. These dates are estimates but they’re good ones. Let’s take a look at who left and who’s coming soon.

Noticable Departures: Who Just Left?

Have you noticed that orchard orioles, northern rough-winged swallows and willow flycatchers are basically gone? They started leaving in July, then rapidly departed in the first week of August. Yellow warblers and purple martins are not far behind. They’ll leave this week.

The screenshot below is a quick summary of rapid departures as of 13 August 2023. It shows:

• Upper Midwest and Northeast region
• Pared down to Noticeable birds (*** or **)
• Sorted by Rapid Migrant Departure date
• Not including some goodies such as Louisiana waterthrush, alder flycatcher and least bittern. (They’re on the website but not “Noticeable” for my pared-down screenshot.)

Noticeable Arrivals: What Rapid Influx will we see this week?

If you haven’t seen them already ruby-throated hummingbirds will make a rapid influx today, 14 August.

The larger region will see increased numbers of common nighthawks and Canada Warblers but in Pittsburgh it’s usually the last week of August.

Here’s a quick summary of Beginning Arrivals as of 13 August 2023 — same parameters as the departures above.

The tables change every day, dropping past dates and picking up new species in the future, so check out BirdCast’s Species on the Move to find out what’s happening near you.

p.s. How will you know if it’s worth going birding? Check BirdCast Migration Tools for forecast maps, live maps and alerts.

(photos from Wikimedia Commons, Charity Kheshgi, Chuck Tague, Kuldeep Singh. Tables are modified screenshots from BirdCast’s Species On The Move for the Upper Midwest and Northeast. Be sure to check BirdCast for the latest data)