Category Archives: Bird Behavior

One Place, One Time, A Quarter Million Warblers

Bird Behavior, Migration
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)

Fewer White-throated Sparrows?

Bird Behavior, Climate Change
White-throated sparrow (photo from Wikimedia Commons)

19 May 2016

A study seven years ago of bird population trends predicted that climate change would cause most species to decline while a few would increase. In May 2016 I wrote about two species whose fates would be different.

More Robins, Fewer White-throated Sparrows

Did this prediction come true?

The maps below show population trends during the non-breeding season. The white-throated sparrow’s trend map for 2007-2020 indicates their abundance dropped 30% in the lower Mississippi area and on the East Coast from New York to North Carolina.

White-throated sparrow non-breeding season population trends 2007-2020 (map from eBird Status and Trends)

Surprisingly, robins experienced regional decline as well, though not in Pittsburgh.

American robin non-breeding season population trends 2007-2020 (map from eBird Status and Trends)

I’ve noticed the drop in white-throated sparrows during their peak migration in early October and mid-to-late April. American robins seem the same as ever here in Pittsburgh

Have you seen a change in white-throated sparrows? Let me know.

(photo from Wikimedia Commons, maps from Cornell University eBird Status and Trends; click on the captions to see the originals)

Update on Morela at the Pitt Peregrine Nest

Bird Behavior, Peregrines
Morela looks ill at Pitt peregrine nest, 8 May 2023 5:34pm (photo from the National Aviary falconcam at Univ of Pittsburgh)

14 May 2023

Two weeks ago I wrote that there would be no peregrine eggs this year at the Cathedral of Learning because Morela was unable to lay any. She crouched and strained but appeared to be egg bound.

Morela stands over the scrape as if to lay an egg but it never comes, 1 May 2023 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Since then Morela has had days when she looks very ill, then seems to recover a little, then looks ill again. Though she stopped standing over the scrape as shown above, she has not returned to her formerly energetic self. Her bleary eyes indicate she feels unwell.

Morela’s bleary eyes indicate she doesn’t feel well, 4 May 2023 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Ecco knows that she is ill.

Ecco knows Morela is ill, 5 May 2023 (photo from the National Aviary falconcam at Univ of Pittsburgh)

He does what he can by bringing her food which he prepares more carefully than usual, as if he’s making it easy to eat. Unfortunately it is not enough.

Ecco carefully prepares food for Morela, 12 May 2023 6:50am (photo from the National Aviary falconcam at Univ of Pittsburgh)

On the morning of 7 May Morela felt bad enough that she left the nest for 36 hours. That day I found her facing the wall in the 38th floor southeast cache area.

She returned to the nest at 5:34pm on 8 May and seemed slightly better but in the next few days her health declined. In this snapshot she is leaning to the side, something she never did when healthy.

Morela lists to her left, 10 May 2032, 8:32pm (photo from the National Aviary falconcam at Univ of Pittsburgh)

During a difficult night on May 11-12 Morela leaned a lot and may have lost her balance a couple of times. On Friday 12 May at 5:51am she left the nest and has not been seen since.

Her long absence and ill health indicate we probably won’t see her again.

Life goes on in the peregrine world. If Morela is gone a new female will come to the Cathedral of Learning to be Ecco’s mate. This year it’s too late to raise a family but if all goes well there will be peregrine chicks next year.

Hoping for happier times ahead.

UPDATE: Well, that didn’t take long! A new, banded FEMALE peregrine came to the nestbox on 14 May at 2:27 PM.

Here she is at the nest this afternoon. I thought this was Morela but when I looked at the image I can see that SHE’S BANDED! (Morela was unbanded.)

(photos from the National Aviary falconcam at Univ of Pittsburgh)

Little Owl Loves The Rain

Bird Behavior, Birds of Prey
Little owl at Terwick Common, UK (photo from Wikimedia Commons)

5 May 2023

After a cold wet week in Pittsburgh it’s hard to imagine being excited about rain but this little owl (Athene noctua) in Britain is loving it. (Yes, “little owl” is his common name.)

Thankfully at last today is bright and sunny in Pittsburgh.

By the way, the little owl of Eurasia could be mistaken in photos for our burrowing owl in the Americas. Both are in the genus Athene and they’re the same size and shape. Here they are side-by-side.

Little owl and burrowing owl (photos from Wikimedia Commons)

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

Parrot-to-Parrot: Video Chat with Friends

Bird Behavior, Musings & News
African gray parrot looks at computer screen (photo from Wikimedia Commons)

3 May 2023

Wild parrots live in flocks and interact with each other all the time but pet parrots often have lonely isolated lives that lead to psychological problems and self-damaging behaviors. We know that video chats help people connect over long distances. Could parrot-to-parrot video chats enrich the pet birds’ lives? The answer “Yes!” was presented at the ACM SIGCHI conference last month.

A research team from Northeastern University, MIT and the University of Glasgow, who study the potential of technology to enrich the lives of pets and zoo animals, enlisted 18 pet parrots and their caregivers in a three-month-long study to connect the parrots to each other online. Even in such a short time the birds became so engaged that they and their caregivers did not want to stop when the study ended.

During the first two weeks, the parrots were taught to ring a bell and touch a screen image of another parrot so that their caregiver would start a video chat with the selected bird.

African gray parrot plays with a bell (photo from Wikimedia Commons)

In the second phase, which lasted two months, the birds were given free reign to request and make calls whenever they wanted. The birds quickly developed favorite video-chat friends with whom they talked, sang and preened. “Parrots who made the most calls also received more calls, suggesting that the study helped the birds become more social. Their caretakers also reported improved bonding with their pets.” — Phys.org.

A parrot in the study video-chatting with Rosie (screenshot from Birds of a Feather Video-Flock Together video)

Here’s how the parrots made friends online.

video from NowThisNews on YouTube

The results were quite exciting in some households.

“We saw some really encouraging results from the study. The parrots seemed to grasp that they were truly engaging with other birds onscreen and their behavior often mirrored what we would expect from real-life interactions between these types of birds. We saw birds learn to forage for the first time, and one caregiver reported that their bird flew for the first time after making a call,” said co-author Dr. Jennifer Cunha who is co-founder of Parrot Kindergarten, Inc. that helped to recruit and train the parrot caregivers for the study.

— phys.org: Video-calling tech could help lonely parrots flock together

Watch a 9-minute video of the study plan and techniques at ACM SIGCHI: Birds of a Feather Flock Together project.

Read more at phys.org: Video-calling tech could help lonely parrots flock together.

(photos from Wikimedia Commons and screenshot from ACM SIGCHI video, click on the captions to see the originals)

Lady Mallards Prepare To Nest

Bird Behavior, Water and Shore
Female mallard (photo from Wikimedia Commons)

10 April 2023

While songbird migration picks up in April, lady mallards are preparing to nest.

Everything about the nest is done by the female. She picks the site, she makes the nest, she lays the eggs, she incubates.

Female mallard nests in urban planter in Göteborg, Sweden (photo from Wikimedia Commons)

Here are some cool facts about mallard nesting (Anas platyrhynchos), gleaned from Birds of the World.

  • Mallards pair up in autumn so they get down to the business of nest site selection as soon as they’ve chosen their breeding home range. The search begins “generally 5-10 days after first Persistent Quacking by hen.” Have you ever noticed first Persistent Quacking? I have not.
  • The pair searches together by “making low circling flights over the area, usually in the evening.” They land together at likely spots, she walks into cover, he waits outside. Watch for this in the evening at Duck Hollow, Wingfield Pines, North Park, etc.
  • “Experimental evidence suggests that mallards and several other dabbling ducks may be able to assess predation risk by detecting predators’ urine.” They can smell the snakes and raccoons!
  • Mallards usually nest on the ground “in upland area near water under overhanging cover or in dense vegetation for maximum concealment.”
  • Urban mallards get creative. They nest in planters, woodpiles, docks, boats, artificial structures and sometimes on buildings.
  • Mallard hens do not carry nesting material to the site. Instead they make a bowl and pull at nearby vegetation to line the bowl with plant litter, leaves, etc. They pull tall vegetation to drape over the nest and increase cover.
  • The first egg is laid 1-4 days after nest site selection. She lays one egg a day usually in the morning. Clutches consist of 1-13 eggs. The larger clutch sizes probably include eggs dumped by other female mallards!
  • She waits to begin incubation until the clutch is complete.
  • During incubation she plucks down from her breast to line the nest and cover the eggs.
  • Recess! “The female usually leaves the nest once in early morning, returning before 9:00 and once in late afternoon, leaving after 16:00. Recess lasts 15–60 minutes.”
  • If something eats her eggs, a wild mallard won’t renest but an urban mallard will. Some urban mallards raise second broods in unnaturally crowded populations.
  • Her chicks hatch in about 28 days.
Female mallard nests by a building. Notice the down she pulled from her breast to line the nest (photo from Wikimedia Commons)

In about 28 days I’ll tell you what happens next.

(photos from Wikimedia Commons; click on the caption to see the original)

Young Peregrines As Home Wreckers

Bird Behavior, Nesting & Courtship, Peregrines
Young intruder female challenges Trailblazer at CVNP/I-80 nest site, 5 March 2023 (photo by Chad+Chris Saladin)

9 April 2023

After reporting on the peregrine drama last Wednesday in Downtown Pittsburgh I went there on Thursday 6 April to investigate. There were no peregrines at Gulf Tower but in just 15 minutes of watching at Third Avenue I saw two peregrines and a possible nest exchange. The departing bird was normal adult color (gray & white) and did a territorial flappy flight as it left. The arriving bird was very dark chocolate brown like the bird in Ann Hohn’s photo on 3 April.

Dark plumage peregrine at the Gulf Tower, approx 3 April 2023 (photo by Ann Hohn)

If this pair is on eggs, the arriving bird’s behavior did not match an incubating female. Instead of quietly moving to the nest the arriving bird called loudly for several minutes. It sounded like “Hey, come back!”

When I mentioned this on Pittsburgh Falconuts Facebook page, Jeff Cieslak remarked: “I’d say that’s pretty good news. But it does raise some questions, neither of the birds I saw on 3/3 were brown.” Here’s the peregrine pair Jeff photographed a month ago.

Female at Third Ave nest Downtown 3 Mar 2023 (photo by Jeff Cieslak)
Male peregrine at Third Ave Downtown, 3 Mar 2023 (photo by Jeff Cieslak)

Correction as of early June 2023: The dark bird is not immature, just dark, and is the mother bird at Third Avenue. … The Theory below is based on incorrect information.

Aha! So the immature bird is an intruder. The quick exit of the adult bird Downtown is like Terzo’s reaction in 2016 when female intruders visited the Cathedral of Learning. Terzo always left quickly and the intruder female always remained at the nest. Adult females were silent but an immature female called loudly. (See this vintage article: Juvenile Female Intruder at Pitt on 8 April 2016.)

Why didn’t the Downtown adult peregrines attack? Peregrine falcon literature says that immature plumage protects young birds from attacks by territorial adults because they aren’t perceived as a threat. Young peregrines won’t breed until they have adult plumage at two years old(*).

… end of bad theory …

In this attack at CVNP/I-80, photographed by Chad+Chris Saladin, Chris explains that the adult male is not brutal to the one-year-old, partly because she’s female and partly because she’s immature.

Young intruder female challenges Trailblazer at CVNP/I-80 nest site, 5 March 2023 (photo by Chad+Chris Saladin)

Yet these one year-old peregrines are disrupting nests. Are they trying to claim territory? Are they thinking about nesting?

Sara Showers reminded me of an article I wrote in 2020: “A year or two ago, it was pointed out to me that one of the factors that causes falcon populations to plateau at the “carrying capacity” isn’t just a finite food supply. When populations are very high, constant competition over nesting sites can cause those contested sites to not produce chicks in a given year – restricting population growth.”

Read about the Home Wrecker phenomenon in this 2020 article, written when Ecco was the young “intruder” and nesting failed that year.

Young Raptors As Home Wreckers

(*) A note from Chris Saladin: “We’ve had 2 females successfully breed when they were just 1 year old, though it certainly isn’t common.”

(blue sky fight photos by Chad+Chris Saladin, adult peregrines at Third Ave by Jeff Cieslak, immature peregrine at Gulf Tower Ann Hohn)

Two Tail-Waggers Are Back in Town

Bird Behavior, Migration, Schenley Park
Eastern phoebe, Carondelet Park, 26 March 2017 (photo by Andy Reago & Chrissy McClarren via Wikimedia Commons)

3 April 2023

On Saturday before the storms I saw my First Of Year eastern phoebes (Sayornis phoebe) in Schenley Park while Kathy Saunders found a first Louisiana waterthrush (Parkesia motacilla) at Tom’s Run Nature Reserve. Two tail-waggers are back in town.

Few birds wag their tails side to side but we do call it “wagging” when they bob or pump their tails up and down. Eastern phoebes are subtle about it but the movement is almost constant and it draws our attention.

Video by GoTrails on YouTube

What makes phoebes wag their tails faster? Predators! Sibley describes a 2011 study of black phoebes:

Avellis concludes that tail pumping is a signal meant to send a message to the predator. It tells the predator that the phoebe has seen it, and therefore the phoebe is not worth pursuing.

— Sibley Guides: Why Do Phoebes Pump Their Tails?

Louisiana waterthrushes don’t just wag their tails. They continuously bob the entire back end of their bodies by moving their ankle joints. Birds’ ankles are the backward “knees,” the middle joint on their legs, hidden by this waterthrush while he dips his butt.

Louisiana waterthrush, April 2020 (photo by Steve Gosser)

His bobbing is like a habit he just can’t quit.

video by Jim Zipp @mcelroyproductions76 on YouTube

Louisiana waterthrushes have a different reason for tail wagging than eastern phoebes and they hold their technique in common with another April migrant, spotted sandpipers.

In case you missed it, here’s why they “wag” their tails.

Why Do They Wag Their Tails?

(photo and video credits are in the captions)

To Lek or Not to Lek: Grackles Lead Different Lives

Bird Behavior, Nesting & Courtship, Songbirds
Male common grackle, puff and “skrinnk” (photo by Norm Townsend via Flickr Creative Commons license)

23 March 2023

Lek: an assembly area where animals (such as the prairie chicken) carry on display and courtship behavior. Also an aggregation of animals assembled on a lek for courtship.

— Merriam-Webster Dictionary

Male prairie chickens hold a lek to attract females and according to this diagram so do “grackles.” It was exciting to think that the puff and “skrinnk” of male common grackles in Pittsburgh was a lek. But it’s not! The three species of grackles in North America lead very different lives.

Common grackles (Quiscalus quiscula), are usually monogamous and may nest alone or colonially with up to 200 pairs in a single colony.

Common grackles, Bill Up Display (photo by Tony Morris via Flickr Creative Commons license)

Bill Up is a male-to-male threat display. The puff and skrinnk is Song during courtship.

Boat-tailed grackles (Quiscalus major), found in Florida and along the Atlantic and Gulf coasts, nest in harems. The males gather in leks to attract the females.

Boat-tailed grackles perform during the breeding season (photo by shell game via Flickr Creative Commons license)
Male boat-tailed grackles on the lek (photo by Judy Gallagher on Flickr via Creative Commons license)

Female boat-tailed grackles are dull brown and laid back compared their male counterparts.

Female boat-tailed grackle (photo by Melissa McMaster via Flickr Creative Commons licnse)

Great-tailed grackles (Quiscalus mexicanus), found west of the Mississippi and in Central America, gather in noisy winter flocks.

Great-tailed grackle flock (photo by Phillip Cowan via Flickr Creative Commons license)

In the breeding season they don’t use leks and they aren’t monogamous.

Great-tailed grackle (photo by designwallah via Flickr Creative Commons license)

Birds of the World explains:

[Their] mating system can be described as non-faithful female frank polygyny, in which a territorial male has one or more social mates, each female has one social mate, and both sexes employ extra-pair copulation as a conditional mating tactic. Territorial males defend a small territory including from 1 to several trees, where one or more females nest. The male protects nestlings hatched on his territory, but not nestlings from other territories. He copulates with his social mates and may attempt to copulate with other females. 

— Birds of the World: Great-tailed grackle account

Frankly, all the great-tailed grackles mess around. Even the females swagger.

Female great-tailed grackle (photo by Charlie Jackson via Flickr Creative Commons license)

Though they’re all called “grackles” they don’t act the same.

(photos are Flickr Creative Commons licensed and credited in the captions, click on the captions to see the originals)

Preparing To Set Up His Harem

Bird Behavior, Nesting & Courtship
Male red-winged blackbird (photo from Wikimedia Commons)

15 March 2023

The guys are back in town! Male red-winged blackbirds returned to western Pennsylvania early this month to get a jump on the breeding season. Males arrive 2-4 weeks before the females in order to shake down who owns what territory before the ladies get here.

Male red-winged blackbird claiming territory (photo from Wikimedia Commons)

The best territories are in the middle of a marsh and claiming a good one is extremely important. When the females arrive they chose a mate based in part on the quality of his territory. If the male and his territory are exceptional, up to 15 females join his harem.

Female red-winged blackbird with nesting material (photo fro Wikimedia Commons)

According to Birds of the World, experiments have shown that females prefer a harem on good territory to being the lone mate of a male on poor territory. Female red-winged blackbirds would rather be one of many wives than alone with one male in a lousy home. With that in mind the males are getting ready to set up their harems.

Watch for the arrival of female red-winged blackbirds in late March or early April. You’ll hear the boisterous clamor of males when they see the flocks of females.

This 3-minute video shows red-winged blackbird behavior in the spring.

video from Cornell Lab of Ornithology on YouTube

(photo from Wikimedia Commons, video from Cornell Lab of Ornithology on YouTube; click on the captions to see the originals)