Category Archives: Migration

Three Waves of Warblers

Migration
Louisiana waterthrush (photo by Steve Gosser in 2018)

21 April 2024

Black Swamp Bird Observatory (BSBO) at Magee Marsh Wildlife Area in Ohio has been banding birds for more than three decades. When they analyzed their warbler data since 1992, the arrivals and departures fell into three distinct waves with the same species in those waves year after year.

This led to their Spring Migration Wave Theory, illustrated on BSBO’s website. I have embedded their graphic and made it tiny on purpose so that you will click on the image to see all the details in the original.

Spring Migration Wave Theory (graphic embedded from BSBO.org): First Wave=red, Second Wave=blue, Third Wave=yellow

BSBO describes the waves and their timing in northwestern Ohio. These timings don’t always apply to Pittsburgh. We are between the Mississippi and Atlantic Flyways, so birds often get here last.

The first wave dominated by male White-throated Sparrow, Hermit Thrush, male Myrtle Warbler, and male Ruby-crowned Kinglet occurs around 25 April [in Northwestern Ohio]. Sub-dominant warblers include the Black-throated Green, Black-and-white, and Nashville. …

The second wave, known as the big wave, occurs 7-13 May [in Northwestern Ohio] and is represented by the greatest species diversity of the spring … The second pulse of this wave coming five to seven days after, usually has the largest volume. …

The third wave normally comes around Memorial Day weekend [in Northwestern Ohio] and is dominated by female Magnolia Warbler, American Redstart, Mourning Warbler, vireos, and flycatchers.

— Black SwamP Bird Observatory: Spring Migration Wave Theory (boldface added)

Which species are in each wave?

In Pittsburgh the First Wave contains species we’ve already seen this month: Louisiana waterthrush, white-throated and fox sparrows, dark-eyed juncos, hermit thrushes, male yellow-rumped (myrtle) warblers, male ruby-crowned kinglets and now, at the end of April, palm warblers.

Palm warblers, two subspecies “Yellow” and “Western” (image by Chuck Tague)

The Second Wave is the Biggest Week in American Birding at Magee Marsh and the biggest couple of weeks in Pittsburgh. Species include stragglers from the First Wave, too.

The Third Wave includes mourning warblers and the rarely-seen-in-Pittsburgh Connecticut warbler. If you want to see a Connecticut warbler at Magee Marsh, their peak is 20-27 May.

Drawing of Connecticut warblers, male and female (image from Wikimedia Commons)

The Spring Migration Wave Theory explains why I’ve never seen some species in May in northwestern Ohio. I thought they didn’t come there but the real reason is that I wasn’t there when they passed through. I’ve always visited Magee Marsh in the second week of May so I’ve never seen a Louisiana waterthrush nor a Connecticut warbler while there.

This year I’m going a week earlier than usual; the BSBO website tells me what I’ll see. Find details on each warbler and its peak at Magee Marsh here (click on the species name to open the details).

Learn more about Spring Migration Wave Theory and the birds in each wave.

(credits are in the captions)

Migration Last Night!

Migration
Blue-gray gnatcatcher (photo by Steve Gosser)
Blue-gray gnatcatcher (photo by Steve Gosser)

17 April 2024

The winds over Pittsburgh were favorable last night and the birds were anxious to head north. There was high migration over southwestern PA and BirdCast tells the tale on their new Migration Dashboard.

Since 2017 we’ve been checking BirdCast for live migration maps and forecasts. This year they’ve supplemented the maps with a Migration Dashboard that provides a wealth of county-by-county information including expected species each night.

Let’s take a look at this morning’s dashboard for Allegheny County, PA.

BirdCast Migration Dashboard: screenshot of Allegheny County, PA on 17 April 2024 at 5:00am

As of 5:00am today, more than a million and a half birds had flown over Pittsburgh but they were slowing down. Live traffic was sparser (50,700 birds in flight), they were moving more slowly (12 mph), and they were losing altitude (1,400 feet). This is normal; they will land before dawn.

The count of birds peaked at midnight (graph on left). It was a really good night for April (graph at right.)

BirdCast Migration Dashboard: screenshot of Allegheny County, PA on 17 April 2024 at 5:00am

You can see an additional reason why the numbers dropped at 5:00am by comparing these two Live Migration maps. At 1:40am the map in Pittsburgh is bright yellow with migrants but a dark hole (no activity) develops in Ohio and West Virginia at 5:00am. Birds stopped flying there because it was raining ahead of a cold front.

screenshots of BirdCast Live maps on 17 April 2024, 1:40am and 5:00am

Who migrated over Pittsburgh last night? The Dashboard shows 14 expected species. (This is a screenshot. Visit Allegheny County’s Dashboard and scroll down to see the rest of the list).

BirdCast Migration Dashboard: screenshot of Allegheny County, PA on 17 April 2024 at 5:00am

I haven’t seen a house wren, yellow warbler or brown thrasher yet this year …

House wren (photo by Chuck Tague)
House wren (photo by Chuck Tague)
Yellow warbler (photo by Chuck Tague)
Brown thrasher bathing in a puddle (photo from Wikimedia Commons)

Did any of them land in Pittsburgh this morning? It’s hard to say. I’ll just have to go birding to find out.

Meanwhile check out the BirdCast Migration Dashboard for your county.

(credits are in the captions. Click the caption links to see the originals)

Yes, We Saw Sapsuckers

Migration, Schenley Park
Yellow-bellied sapsucker, Schenley Park, 14 April 2024 (photo by Charity Kheshgi)

15 April 2024

Twelve of us gathered in yesterday’s perfect weather for an outing in Schenley Park.

Schenley Park outing, 14 April 2024 (photo by Kate St. John)

When I announced the outing, I said we had a good chance of seeing yellow-bellied sapsuckers and indeed we did — at least four plus an interesting interaction between a male and female.

Was this pair migrating together? Birds of the World says Not likely. Male yellow-bellied sapsuckers migrate first, the females follow later. When the males reach the breeding grounds they drum and squeal to establish territory and attract a mate. There was no drumming and squealing in Schenley (they don’t breed here) but the two birds followed each other from tree to tree. One of them seemed annoyed. Was the other “stealing” sap from his/her holes?

There were plenty of holes to choose from. The sapsuckers redrilled old rings on shagbark hickories and made new rings on tuliptrees.

Yellow-bellied sapsucker sipping sap from a tuliptree, Schenley Park, 14 April 2024 (photo by Charity Kheshgi)

We also saw nest building among blue jays (a pair) and red-winged blackbirds (just the female) …

Blue jay carrying nesting material, Schenley Park, 14 April 2024 (photo by Charity Kheshgi)

… and a pair of red-tailed hawks incubating eggs in last year’s successful nest under the bridge.

Red-tailed hawk on nest under PH Bridge, Schenley Park, 14 April 2024 (photo by Charity Kheshgi)

There aren’t many wildflowers in Schenley Park because of abundant hungry deer but we saw a few foamflowers (Tiarella sp) in an inaccessible spot.

Foamflower in bloom, Schenley Park, 14 April 2024 (photo by Charity Kheshgi)

Can you see the flying honeybees and honeycombs in this photo? The hive is so high up (20-30 feet) that we wouldn’t have seen it if we hadn’t been looking for birds.

Honeybee hive way up high in a hollow branch, Schenley Park, 14 April 2024 (photo by Charity Kheshgi)

In all, we saw 33 species and lots of breeding behavior. Our last sighting was a surprise: two bald eagles, an adult and an immature, circling northward in Junction Hollow. I wondered if one of the Hays eagles was escorting an immature intruder away from the Hays nest.

See our checklist below and online at https://ebird.org/checklist/S168641182

Schenley Park, Allegheny, Pennsylvania, US
Apr 14, 2024, 8:30 AM – 10:45 AM, 33 species

Canada Goose (Branta canadensis) 4
Mourning Dove (Zenaida macroura) 2
Cooper’s Hawk (Accipiter cooperii) 1 Immature
Bald Eagle (Haliaeetus leucocephalus) 2 One adult & one immature flying/soaring up Junction Hollow.
Broad-winged Hawk (Buteo platypterus) 1
Red-tailed Hawk (Buteo jamaicensis) 2
Yellow-bellied Sapsucker (Sphyrapicus varius) 4 Drilling and sipping sap, especially on trees with well established sapsucker rings on bark.
Red-bellied Woodpecker (Melanerpes carolinus) 2
Downy Woodpecker (Dryobates pubescens) 4
Northern Flicker (Colaptes auratus) 6
Eastern Phoebe (Sayornis phoebe) 2
Blue Jay (Cyanocitta cristata) 7 Two jays carrying nesting material to same nest area.
Fish Crow (Corvus ossifragus) 1 Heard
Carolina Chickadee (Poecile carolinensis) 5
Tufted Titmouse (Baeolophus bicolor) 4
Northern Rough-winged Swallow (Stelgidopteryx serripennis) 4
Ruby-crowned Kinglet (Corthylio calendula) 2
Golden-crowned Kinglet (Regulus satrapa) 2
White-breasted Nuthatch (Sitta carolinensis) 2
Brown Creeper (Certhia americana) 2
Carolina Wren (Thryothorus ludovicianus) 4
European Starling (Sturnus vulgaris) 5
American Robin (Turdus migratorius) 6
House Finch (Haemorhous mexicanus) 5
American Goldfinch (Spinus tristis) 3
Chipping Sparrow (Spizella passerina) 1
Dark-eyed Junco (Junco hyemalis) 4
White-throated Sparrow (Zonotrichia albicollis) X Heard
Song Sparrow (Melospiza melodia) 5
Red-winged Blackbird (Agelaius phoeniceus) 9 Female building a nest.
Brown-headed Cowbird (Molothrus ater) 3
Common Grackle (Quiscalus quiscula) 3
Northern Cardinal (Cardinalis cardinalis) 6

(all photos by Charity Kheshgi except for the people-photo by Kate St. John)

Seen This Week

Migration, Phenology, Plants & Fungi
Fox sparrow singing at Frick Park, 12 March 2024 (photo by Charity Kheshgi)

16 March 2024

Four days this week were unseasonably warm with highs 18 to 20+ degrees above normal. The flowers and birds responded.

On Tuesday, Charity Kheshgi and I heard a fox sparrow at Frick Park but he was elusive. We spent a long time trying to get a good look him until a blue jay’s weird call made us pause. So did the fox sparrow, as shown above in Charity’s photo.

On Wednesday there were few birds at Toms Run Nature Reserve but we saw purple dead nettle (Lamium purpureum) in bloom.

Purple dead nettle, Toms Run, 13 March 2024 (photo by Kate St. John)

On Thursday 14 March I was surprised at the lack of birds at Raccoon Creek Wildflower Reserve, but the flowers on the Jennings Trail cliff face (bordering the creek) were responding to the heat. It’s not Full Blown Spring yet but I found:

Harbinger of Spring, Raccoon Creek Wildflower Reserve, 14 March 2024 (photo by Kate St. John)
Spring beauty, Raccoon Creek Wildflower Reserve, 14 March 2024 (photo by Kate St. John)
Sharp-lobed hepatica, Raccoon Creek Wildflower Reserve, 14 March 2024 (photo by Kate St. John)
Round-lobed hepatica, Raccoon Creek Wildflower Reserve, 14 March 2024 (photo by Kate St. John)
Virginia bluebell budding flower, Raccoon Creek Wildflower Reserve, 14 March 2024 (photo by Kate St. John)
Alder catkins, Raccoon Creek Wildflower Reserve, 14 March 2024 (photo by Kate St. John)

And in case you missed it Carla, the female peregrine at Pitt, laid her first egg at the Cathedral of Learning on 14 March. Additional eggs are expected approximately 48 hours apart.

Happy 2024 Egg Day! 1st Peregrine Egg at Pitt

(credits are in the captions)

Most Spectacular Raptor Migration in the World

Birds of Prey, Migration, Southern Africa, Travel
Amur Falcon, male in South Africa (photo from Wikimedia Commons)

27 January 2024: Day 9, Chobe National Park, Botswana — Road Scholar Southern Africa Birding Safari. Click here to see (generally) where I am today.

Amur falcons (Falco amurensis) breed in Siberia and northern China and travel 22,000 km (13,670 mi) each fall to southern Africa. Not only is their migration the longest of all the raptors but when they stopover in autumn to refuel in Nagaland, India their flock can number half a million birds. Right now they’re in southern Africa where I hope to see them.

Amur falcons are insectivores who, on migration, capture flying insects to eat in mid air.

Male Amur falcon eating an insect in flight in South Africa (photo from Wikimedia Commons)

They time their migration and choose a route to take advantage of insect swarms.

  • In northeastern India winged adult termites swarm in autumn in Nagaland.
  • Over the Arabian Sea dragonflies migrate in the fall from India to Africa.
  • In southern Africa, December to March rains spawn swarms of termites, locusts, ants and beetles.
Range map and migration route of Amur falcon (image from Wikimedia Commons, annotated)

Amur falcons are present from October to December near the Nagaland village of Pangti where they fatten up on termites before continuing their journey. There are hundreds of thousands of falcons in the air at once.

video embedded from Ace Ventura on YouTube

Their abundance led to near tragedy, however. Until the practice ended in 2012, Nagaland hunters caught tens of thousands of falcons per day in fishing nets hung from the trees. Each year they killed 250,000 Amur falcons to sell as meat for mere pennies. They thought the falcons would never disappear.

The killing ended abruptly when journalist Bano Haralu returned to her homeland, witnessed the destruction, and got a hunting ban placed in November 2012. More importantly, she and her colleagues taught the villagers, and especially the children, the importance of the falcons and a way forward through ecotourism. It was a stunning turnaround and a credit to the people of Nagaland.

Amur falcons gather at Pangti, Nagaland, India on migration (photo from Wikimedia Commons)

In 2018 Scott Weidensaul went to Pangti to see the birds and tell their amazing story in A Galaxy Of Falcons: Witnessing The Amur Falcon’s Massive Migration Flocks. Birders flocked to the spectacle last fall.

UPDATE on 29 January 2024: I was fortunate to see a female Amur falcon in Namibia today, swooping for insects near the Chobe River. (These photos are from Wikimedia.)

Female Amur falcon, South Africa (photo from Wikimedia Commons)

For more information see:

Will Pittsburgh Get Cold Enough for Rare Gulls Next Week?

Migration, Water and Shore, Weather & Sky
Watching gulls at the Point, Pittsburgh, PA Jan 31, 2015 (photo by Tim Vechter)
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?

Low temperature forecast for Monday 15 January 2024 as of 11 Jan ( from the NWS)

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).

Eastern Great Lakes Ice Chart as of 10 Jan 2024 (map from North American Ice Service)

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.

(credits are in the cations)

Eats Fruit and Leaves

Bird Behavior, Migration
American robin eating fruit in early winter, Toronto (photo from Wikimedia Commons)

23 December 2023

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.

White Stork Transmitter Goes Roaming in Sudan

Migration, Water and Shore
White stork flock in Africa (photo from Wikimedia Commons)

20 October 2023

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.

White stork migration paths (map from Wikimedia Commons) Blue Nile Valley in Sudan is circled in yellow

In April 2017 a white stork in Poland, nicknamed Kajtka, was tagged with a transmitter containing a mobile SIM card.

SIM card T–Mobile Poland (image from Wikimedia Commons)

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.

— White Stork transmitter racks up massive phone bill

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!

video from The Wildlife Channel on YouTube

(credits are in the captions)

Hundreds of Grackles in the Trees

Bird Behavior, Migration
Common grackle flock moving through the trees, Patuxent Research Refuge, Nov 2021 (photo from Wikimedia Commons)

18 October 2023

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.

Common grackle flock on the ground at Patuxent Research Refuge, Nov 2021 (photo from Wikimedia Commons)
Common grackle flock starting to swirl up at Patuxent Research Refuge, Nov 2021 (photo from Wikimedia Commons)
Common grackle flock mostly flown away at Patuxent Research Refuge, Nov 2021 (photo from Wikimedia Commons)

Get To Know Nature in New Jersey shows what it’s like to be in the forest with hundreds of grackles.

video by Get To Know Nature on YouTube

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.

Common grackle sightings, Dec-Feb, past 10 years (retrieved from eBird on 3 Mar 2022)

But for now we have hundreds of grackles in the trees.

(credits are in the captions; click on the captions to see the originals)

Birds Take a Taxi to Correct For Climate Change

Climate Change, Migration
Male European pied flycatcher (photo from Wikimedia Commons)

9 October 2023

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.

Female European pied flycatcher carrying caterpillars (photo from Wikimedia Commons)

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.”

Range of European pied flycatcher (map from Wikimedia Commons)

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.

Read more about the taxi ride experiment in Anthropocene Magazine: For some birds, a “taxi” helps recalibrate out-of-sync migrations.

(photos and map from Wikimedia Commons; click on the captions to see the originals)