Watching gulls at the Point, Pittsburgh, PA, 31 Jan 2015 (photo by Tim Vechter)
11 January 2024
Only a few days ago I was lamenting that we weren’t having a snowy winter, neither snow nor snowy owls. Well, be careful what you ask for! A few days of bitter cold are coming to Pittsburgh next week. If Lake Erie freezes, arctic gulls will fly south to find open water on the rivers. The photo above shows some cold and happy birders looking at rare gulls at the Point in January 2015.
So what are the chances this will happen next week?
As of this morning, the forecasted low temperature for dawn on Wednesday 17 January is 9°F. This map for next Monday sure looks like we’re in a “polar vortex.” Cold, right?
But will it be cold long enough to freeze Lake Erie and send the gulls south? Probably not. The eastern Great Lakes ice map as of yesterday, 10 Jan 2024, shows nearly 100% open water (white).
There’s not even a hint of ice (blue) on most of Lake Erie and the Great Lakes ice-to-date graph for winter 2023-24 indicates that ice is at a near record low. There’s a lot of cooling off to do before the lakes will freeze.
So next week I’ll have to wear my Minnesota gear to go outdoors but it’s unlikely there will be any unusual birds out there. Will I want to go out in 9°F anyway? I’ll have to wait and see.
Early this week a big flock of American robins came to my neighborhood, ate all the fruit they could find, and left.
On Monday morning, 18 December, they were frantically eating this pyracantha fruit outside my window. At one point I counted 45 but they were moving so fast I think there were more.
Pyracantha full of fruit, 23 Nov 2023 (photo by Kate St. John)
The birds were frantic because they knew bad weather was coming. In mid afternoon it snowed.
Snow flurries 18 December 2023, 3pm (photo by Kate St. John)
The next morning the fruit was gone and so were the robins.
Sam pyracantha with no more fruit, 19 December 2023 (photo by Kate St. John)
American robins are still in Pittsburgh but they’re feasting in other locations. When the fruit is gone and the ground is frozen, the robins will leave.
p.s. Today’s title reminds me of the 2006 bestselling book on punctuation by Lynne Truss called Eats, Shoots and Leaves. The comma in her book title is really important. Did the panda eat, shoot a gun, and then leave? Or did the panda eat two things — shoots and leaves? … In the case of today’s blog title: Robins don’t eat leaves. They eat fruit and leave the neighborhood.
Most people who find discarded bird tracking technology don’t know what they’re looking at and even when they do they don’t usually repurpose it. But every once in a while a transmitter goes roaming.
White storks (Ciconia ciconia) that breed in Poland migrate to eastern and southern Africa for the winter. For some, their final destination is the Blue Nile River valley, circled in yellow on the map below.
That autumn she flew to the Blue Nile River valley in Sudan where she became mysteriously inactive. Eventually she stopped moving altogether and had either died or the transmitter fell off. Researchers couldn’t figure out what happened until they got the phone bill.
Questions were raised when Kajtka lingered in the area for more than eight weeks, only roaming around 25 km [15 miles] in various directions.
In 2018, the mystery was solved when EcoLogic Group received a phone bill for 10,000 Polish zloty, the equivalent of £2,064 [$2,500]. Someone had picked up the tracker in Sudan and taken the opportunity to make 20 hours of phone calls using the SIM card.
Fortunately for cash-starved bird research this sort of episode is rare.
If Kajtka had survived she would have joined her fellow white storks moving north in March, perhaps with a stopover in the Hula Valley shown below. Gorgeous!
This month a flock of 100 to 200 common grackles has been hanging out at Frick Park, chattering in the trees and swirling in a dense flock whenever they’re disturbed. This is typical fall behavior for grackles and blackbirds but I wondered why they picked the park.
According to Birds of the World, common grackles (Quiscalus quiscula) are not very territorial during the breeding season and drop all rivalry in fall and winter. On migration and at overwintering sites they prefer to roost and feed in huge flocks, sometimes mixed with other blackbirds and some robins.
Common grackles roost near plentiful food but they don’t require wild places. Urban roosts are often favored on tree-lined streets or in parks. Their fall roosts in New Jersey can contain 3,000-500,000 birds (of which grackles comprise 33%).
This flock at Patuxent in Maryland looks to be 100% grackles.
The huge grackle flocks probably won’t stay in southwestern PA for the winter. By December they are further south, as shown on the eBird Dec-Feb map below.
Birds like the European pied flycatcher (Ficedula hypoleuca) that winter in the tropics and southern hemisphere do not use weather clues to tell them when to fly north in the spring. Instead they cue on changing day length and return at the same time every year. But as Earth’s climate changes, spring comes weeks earlier than it used to and their migration timing is out of sync. Scientists in the Netherlands decided to give a few lucky birds a lift (a Lyft?) to Sweden and it made all the difference.
Pied flycatchers prefer to nest in or near oak trees where their nesting season is timed to correspond with the peak of caterpillar season. Unfortunately, spring is two weeks earlier now in the Netherlands, pied flycatchers arrive too late and have locally experienced a 90% decline.
The old timing of Netherlands’ spring is now found in southern Sweden so scientists at University of Groningen in the Netherlands and Sweden’s Lund University decided to see what would happen to migration and nesting success if a few pied flycatchers were transported (by car!) from the Netherlands to suitable habitat in Sweden.
Anthropocene Magazine reports, “For three springs, starting in 2017, scientists from the University of Groningen in the Netherlands and Sweden’s Lund University caught newly-arrived Dutch female pied flycatchers and drove them by car to a nesting spot 570 kilometers (354 miles) away in southern Sweden that was already home to other pied flycatchers.”
The experiment was wonderfully successful. The Netherlands’ females were in sync with the food supply and were twice as prolific as their Swedish counterparts who were locally out of sync. After spending the winter in Africa the former-Netherlands females returned to Sweden and so did their offspring!
Later the research team proved that migration timing is genetically inherited in European pied flycatchers by taxiing a few eggs laid in the Netherlands to Swedish nests. Those offspring returned to Sweden the following spring on the Netherlands timing.
Taxi service cannot be the answer to out of sync migration but birds are adapting on their own. During the study, banding still continued at Netherlands nests and some of those youngsters were found nesting in Germany, halfway to Sweden. They flew there on their own.
The blackpoll’s transoceanic path was proven in a 2015 study by Bill DeLuca and the Vermont Center for Ecostudies. VCE writes:
Bill DeLuca (Northeast Climate Science Center) and VCE solved this great modern-day avian mystery. Using light-level geolocators attached to Blackpoll Warblers in Vermont and Nova Scotia, DeLuca and colleagues documented the longest distance non-stop overwater flights ever recorded for a migratory songbird. During October, Blackpoll Warblers initiate a ~3-day non-stop transoceanic flight of ~2500 km from the north Atlantic Coast to Hispaniola and Puerto Rico. Radar data show migrating songbirds fly at 2,600 to 20,000 feet while making this journey. After a few weeks, they fly onto Columbia or Venezuela where they overwinter. Their spring migration route takes them over Cuba to Florida, where they journey up the eastern US seaboard to reach their breeding grounds in late May.
Of course I wondered if blackpoll warblers sleep in flight during their 3 day transoceanic trip, but we won’t find out any time soon. Blackpolls are way too small to wear the sleep monitoring gear used on the great frigatebird.
(photo from Wikimedia Commons, maps from eBird Weekly Abundance; click on the captions to see the originals)
Hermit thrush banded at Bird Lab, Hays Woods, 3 Oct 2023 (photo by Jared Miller)
4 October 2023
Joe, Sam and Jared joined me yesterday morning on an adventure to see Bird Lab at Hays Woods. The weather was perfect as we walked more than half a mile to the banding station. There we found Nick Liadis and his assistants about to do the second net-check of the day.
The mist nets that capture songbirds are set up in “alleys” of vegetation where birds might fly across. If a bird doesn’t see the net and tries to fly through, it falls into the pocket of extra netting material where it waits to be retrieved. Banders check the nets every half hour.
Bird banding mist net at Hays Woods, 7 Sep 2022 (photo by Kate St. John)
Captured birds are brought back to the banding table in cloth bags to keep them calm. Our group watched as Nick prepared to band three birds from the recent net check.
Bird Lab at Hays Woods: 3 workers (orange vests) and three observers, 3 Oct 2023 (photo by Kate St. John)
Each bag contains a surprise. The first was a recaptured Cape May warbler (Setophaga tigrina), originally banded on 20 Sep when it weighed 10.9g. Yesterday it weighed 13.8g for a gain equivalent to the weight of a ruby-throated hummingbird. Such a small bird in Nick’s hand, below.
Nick Liadis holds a Cape May warbler recaptured at Hays Woods on 3 Oct, first banded on 20 Sept 2023 (photo by Kate St. John)
It was the second Cape May warbler recapture this fall. The first one increased its weight by 50% in two weeks. About the first one, Nick wrote:
A cool recapture from my Hays Woods banding station! This Cape May Warbler was banded on 9/13 and we captured her again two weeks later. She originally weighed 11.6g and today weighs 15.4g. Interesting to see how long some of these birds hang around. I’d imagine she’ll be on her way very soon.
— Nick Liadis message, 27 Sep 2023
Next on the agenda was a hatch year (meaning “hatched this year”) male black-throated blue warbler (Setophaga caerulescens). His color was blue, but not vibrantly so, and his throat had tiny white flecks on it. I had seen a dull bird like this in Frick Park last week and didn’t realize that meant he was young.
BirdLab at Hays Woods: Hatch Year male black-throated blue warbler in partial adult plumage, 3 Oct 2023 (photo by Jared Miller)
At each successive net check new species showed up.
The hatch year hermit thrush (Catharus guttatus) shown at top was a sign that the mix of migrant species is changing. The insect eaters are nearly gone while the fruit and nuts migrants have arrived (*see note).
The hatch year female house finch, below, was probably born at Hays Woods. Many house finches in the eastern U.S. are permanent residents. Perhaps she will be, too.
BirdLab at Hays Woods: Hatch Year female house finch, 3 Oct 2023 (photo by Kate St. John)
BirdLab at Hays Woods: Ovenbird, 3 Oct 2023 (photo by Kate St. John)
By 10:00am we’d been there an hour, it was getting hot (the high yesterday was 85°F!) and the birds were less active. Three of us hiked to the overlook and returned for one more net-check. This time only one bird was captured, a hatch year house wren (Troglodytes aedon) that Nick had banded on 9 August. This bird has spent the last two months foraging at Hays Woods and soon it will migrate to Central or South America.
BirdLab at Hays Woods: House wren, 3 Oct 2023 (photo by Jared Miller)
Thanks to Jared Miller for sharing his photos, shown above.
Bonus Bird: After the banding, a rare bird at Duck Hollow:
At 10:30am I received an alert that a migrating American avocet (Recurvirostra americana) was hanging out at Duck Hollow. Avocets in Allegheny County are One Day Wonders. I had never seen one here because I waited a day to go see them. So I made the short trip from Hays Woods to Duck Hollow and digiscoped this lousy picture. The light was too bright to see its faint orange color but you get the idea.
American avocet at Duck Hollow, 3 Oct 2023 (photo by Kate St. John)
p.s. (*) Two of the phases of fall migration: ** Insect eaters such as warblers, flycatchers, swifts and swallows migrate through in September because the bug population is going to die when cold weather hits. ** Fruit and nut eaters, including thrushes and sparrows, pass through in October.
Magnolia warbler in fall, Sept 2018 (photo by Dave Brooke)
19 September 2023
Right now warbler migration is at its autumn peak in southwestern Pennsylvania but, as usual, the birds are hard to identify. Their fall plumage is dull and confusing, they move fast so we never get a good look at them, and we don’t get much practice because many of them are here only in September. And then they’re gone.
This year it dawned on me that the magnolia warbler (Setophaga magnolia) is super-easy to identify if all you see is its butt, as shown at top and below.
Note that the magnolia warbler is the only warbler with a white belly, white undertail coverts, white undertail and a large black straight-edged tip on the tail. It looks as if this warbler was dipped tail first in black paint.
I highly recommend the 560-page The Warbler Guide by Tom Stephenson and Scott Whittle which I use at home after noting the warbler’s key features in the field. In my opinion the book is indispensable if you take photographs.
For nearly 30 years ultralights have been used to establish safe migration routes for endangered geese and cranes as they are reintroduced to the wild.
In 1993 ultralight pioneer Bill Lishman, along with Joe Duff, conducted the first ever human-led bird migration by guiding a small flock of young Canada geese from Ontario to Virginia. His experiment proved that young geese imprinted on an ultralight will follow the aircraft and learn the migration route. After leading the birds just once, in one direction, the geese knew the route and returned on their own in the spring.
Christian “Birdman” Moullec was the first to do it in Europe when he guided lesser white-fronted geese (Anser erythropus) from their future breeding grounds in Sweden to new wintering grounds in Germany in 1999. He has since led red-breasted geese (Branta ruficollis) and many other species.
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.
Greater and lesser yellowlegs, April 2020 (photo by Lauri Shaffer)
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!
Nick Liadis checking the age of an ovenbird, Sept 2022 (photo by Kate St. John)
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.
Magnolia warbler in autumn (photo by Steve Gosser)
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!
