Category Archives: Nesting & Courtship

Baby Doves Get Taken For A Ride

Juvenile mourning dove on a fence, 2008 (photo from Wikimedia Commons)

15 August 2023

Last Sunday while Bob Donnan was at the Pirates’ game, two young birds nestled in the windshield wiper well of his car.

Yesterday [13 August] when our Chevy Bolt was parked at the South Hills Village – Public Rapid Transit garage, two young [Mourning] Doves nestled into the lower windshield area. We didn’t even notice them until exiting the garage into brighter light! 

The car is so quiet that their short ride didn’t alarm them. After I stopped the car and waited for all traffic to pass, I waved my hand toward them and they flew off, back toward the parking garage.

— email from Bob Donnan, 14 August 2023
Immature mourning doves are surprised to take a ride (video by Bob Donnan)

I could tell by the birds’ appearance that they are juvenile mourning doves because they look spotty rather than smooth. Juvenile body feathers are so new that each one has a pale tip, giving the bird a scalloped look. Compare the top photo of a juvenile with this one of an adult.

Mourning dove adult (photo from Wikimedia Commons)

Why did the two birds hang out together?

Mourning doves (Zenaida macroura) nest multiple times per season and at each nesting the female lays two eggs that hatch in 14 days and fledge 12-15 days later. Just before they fledge the father completely takes over feeding duty so his mate can cycle and lay a new clutch.

The siblings are dependent on their father for 12-15 days after they fledge (26-30 days old). During this period they stay together in the same area during the day, never straying far, waiting for dad to show up. In the nest they learned to associate his voice with a feeding so if he calls they come.

Interestingly they have good homing skills even at this young age. If juveniles are forced from their “reference area” before they are 21 days old — i.e. while still dependent on their father — they always return within 24 hours.

Why at the parking garage?

Mourning doves nest in trees, shrubs and even on the ground but they have no problem nesting near humans and, according to Birds of the World, “may use unusual human-made substrates for nest sites, e.g. rain spouts, mops hanging on walls, immobile car accessories.”

Hmmm. “Immobile car accessories.” These two are probably not the only baby doves who’ve been taken for a ride.

(photos from Wikimedia Commons, video by Bob Donnan)

Listen For Merlins Nesting Near You

Merlin family at Chatham University, Pittsburgh, PA, July 2022 (photo by Malcolm Kurtz)

25 June 2023

Last year Malcolm Kurtz found the first recorded merlin nest in Allegheny County when he heard them on Chatham University’s campus. They were easy to find because merlins are extremely vocal during the breeding season, especially late June through July when their young beg loudly. If you recognize the sound you may discover merlins nesting near you. In Pennsylvania this is a very big deal and Don Nixon, who tracks Pennsylvania’s merlins, wants to know about it.

Merlins (Falco columbarius) are small, streaky, dark, very fast falcons about the size of pigeons who, after the DDT crash, did not nest in Pennsylvania for over 30 years. When they returned they chose old unmodified crow or hawk nests in conifers in forests, cities, residential areas, school yards, parks, cemeteries, and golf courses.

Don Nixon has seen merlin numbers grow quickly in recent years and writes:

  • We now have over 100 documented merlin nests across Pennsylvania since 2006.
  • Nest sites stretch from a repeatedly used area at Promised Land State Park in the Poconos to a golf course in Somerset.
  • Nests have been reported in 24 of Pennsylvania’s 67 counties.
  • Counties reporting nests for the first time in 2022 include Allegheny (Malcom’s nest), Blair, Cameron, Clarion, Columbiana and Somerset. 
  • This year Lackawanna County is already reporting its first nest.

Don publishes an annual PA merlin map after the breeding season, 2022 shown below. The dots appear clustered because there are few observers.

Pennsylvania merlin nests in 2022 (map from Don Nixon)

Since merlins don’t use the same nest site in consecutive years these dots don’t tell you where to find merlins this year. Instead you’ll have to listen for them. The two most common calls, described by Birds of the World, are:

  • Ki-Ki-Kee (Kek-Kek-Kek) given in courtship displays, territorial or other aggressive encounters,
  • Food Begging Whine: a monotonous call, given by female soliciting food transfers from male. Sometimes given after copulation. Also given by nestlings but softer and quicker.

Here are three examples:

Alarm near the nest, Xeno Canto 666137:

Female calling after mating with male, Xeno Canto 642023:

Adults and begging juvenile, Xeno Canto 583041:

If you hear these sounds look for merlins. If you heard them in Pennsylvania, Don Nixon wants to hear from you. Add your own dot to the PA Merlin Map. Contact Don at:

Don Nixon
1009 Green Glen Drive, DuBois, PA  15801
814-661-5944 (cell)
pamerlins@gmail.com

Now’s the time to listen for merlins. Maybe you’ll find a nest!

(photo by Malcolm Kurtz, map from Don Nixon)

Both Hays Eaglets Have Fledged

Young bald eagle, H19, flies near the Hays bald eagle nest, 15 June 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

17 June 2023

I missed it! As of Thursday both young bald eagles, already as large as their parents, had fledged from the Hays bald eagle nest.

Dana Nesiti (Eagles of Hays PA on Facebook) photographed the first one in flight (H19) and the second perched in a tree (H20) on Thursday 15 June.

H19 fledged on Sunday 11 June and was flying really well by Thursday.

Young bald eagle, H19, flies near the Hays bald eagle nest, 15 June 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)
Young bald eagle, H19, flies near the Hays bald eagle nest, 15 June 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

H20 was new to flying and less ambitious.

Young bald eagle, H20, flew from the Hays bald eagle nest, 15 June 2023 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

Their names, H19 and H20, indicate they are the 19th and 20th eagles to fledge from the Hays nest since it began 10 years ago.

See a summary of this year’s nesting season at Eaglestreamer’s Hays Update page.

Stop by the Hays Bald Eagle Viewing Area on the Three Rivers Heritage Trail to see them fly near home. Click here for directions.

(photos by Dana Nesiti at Eagles of Hays PA on Facebook)

Watch Kestrel Family “Live”

Male kestrel incubates eggs in Yorkshire, UK (screenshot from Robert E Fuller video)

16 June 2023

In North America we call our smallest falcon a “kestrel” (Falco sparverius) because it resembles the well known Eurasian or common kestrel (Falco tinnunculus) in Europe. Both are cavity nesters that use holes in cliffs, trees or buildings.

Wildlife artist and blogger Robert E Fuller (@RobertEFuller) has live nest cameras at his farm in Yorkshire, England including two on common kestrel nests. When he tweeted this video three days ago the eggs in Jeff and Jenny’s nest were about to hatch. Yesterday the first three hatched. Today the chicks are growing fast and the last egg awaits.

Watch more nature videos on Robert E. Fuller’s channel on YouTube.

p.s. The Live stream is a composite of many nests. Jeff & Jenny’s is at top right, as highlighted below in the screenshot.

screenshot from Robert E Fuller Live Cams on YouTube

Who’s The Biggest Threat to a Nest?

Raccoon in a tree (photo from Wikimedia Commons)

13 June 2023

When I saw a blue jay eating a baby bird in Schenley Park last week I jumped to the conclusion that jays are a huge threat to nesting birds … but are they? A 2016 analysis of 53 North American nest-predator studies, comprising more than 4000 camera-monitored nests, found that the top predators are far different than I expected. The biggest threat to a nest varies by region, habitat, the size of nesting adults, and the height of the nest.

Across the North American continent about 37% of nest predation is done by mammals, a combination of “mesopredators” (raccoons, foxes, squirrels) and rodents.

The proportion of known-identity predation events attributed to each major nest-predator guild from 1917 nest-predation events (graph from DeGregorio et al, BioScience, Aug 2016, colors added)

The most likely predator varies by region. Hot colors on the maps below indicate the top category of predators.

The predicted predator-specific nest-predation probabilities across North America for (a) corvids, (b) mesopredators, (c) snakes, and (d) rodents (DeGregorio et al, BioScience, Aug 2016)

One of the 53 studies, published in 2007, listed predation counts by species in the continental U.S. Thompson et al’s top six nest predators are shown in the slides below.

  • #1. Rat Snake

Interestingly southwestern PA doesn’t have a single top predator because there are so many to choose from. Fortunately, even though predator richness is greatest at mid-latitudes (such as Pittsburgh), it is a poor predictor of predation probability.

So who’s one of the top nest predators in Pittsburgh? He’s looking at you (at top).

(photos from Wikimedia Commons, annotated maps and graphs from Nest Predators of North American Birds: Continental Patterns and Implications, DeGregorio et al, BioScience, August 2016)

(*) Perhaps this is The Revenge of the Mammals: When dinosaurs, birds’ ancestors, ruled the Earth they feasted on mammals, all of whom were tiny and hid underground. Now the tables are turned and small birds are at the mercy of mammals.

The Intriguing Mystery of Downtown’s Dark Bird

Dark brown female at Third Avenue Downtown, perched on Lawrence Hall, 5 June 2023 (photo by Jeff Cieslak)

11 June 2023

This spring Downtown Pittsburgh’s peregrines were so confusing that for two months we weren’t even sure of their age and sex. By now we know that the male at Third Avenue is Terzo and the dark brown bird is female. Why is this bird so dark? The mystery is intriguing.

Wrong ID for the dark bird:
In early April Jeff Cieslak and I were both convinced the dark brown bird was a one-year-old male because we saw it enter the Third Avenue nest carrying prey even though the eggs had not hatched yet. After all, male peregrines bring prey to incubating females and immature birds have brown plumage … don’t they?

Solve the easy ID first: Who is the banded white-chested bird?
Jeff Cieslak’s April and May photos show that the gray-and-white adult has black/red bands. Also, several viewers remarked that the bird’s face is like Terzo in other photos. This bird is the male, Terzo.

Terzo at Third Avenue Downtown perched on Lawrence Hall, 5 June 2023 (photo by Jeff Cieslak)

Is the dark bird immature?
No. Adult plumage has horizontal stripes on the flanks and belly, immature plumage has vertical stripes. Compare these side-by-side adult and juvenile peregrines photographed at Third Avenue.

Comparing peregrine adult vs juvenile plumage: Adult plumage has horizontal stripes, juvie plumage has vertical stripes (photos digiscoped by Kate St. John)

Is the female completely dark brown? No. This photo of her back shows it is grayer in color than her belly.

Dark brown female is grayer on her back, 3 June 2023 (photo by Kate St. John)

Why is this bird so dark?
I sent photos to Art McMorris, retired PA Game Commission Peregrine Coordinator, and asked: “This adult at the Third Ave nest site Downtown is very brown and not banded as far as we can see. It doesn’t have juvenile vertical stripes on flanks and chest. I don’t know what to make of this coloration.”

Art’s reply includes a Peregrine Reintroduction discussion in the third paragraph:

This is indeed a very puzzling-looking bird. I’m looking at these 3 photos and the photo Jeff Cieslak took on 4/14. All show the horizontal banding typical of adult peregrines, not juveniles. But it is very brown, atypical of adults. It is much grayer in the third photo you sent; nowhere near as brown but still very dark.

Structurally, it looks like a typical peregrine to me.

Taking all of this together, I’d say it is reminiscent of pealei [Pacific Northwest subspecies]. Pealei is non-migratory, so I wouldn’t suggest that it might be a bird from the Pacific Northwest, but pealei is also one of the 7 subspecies used for captive breeding and release. And occasionally genetic recombination in the wild population results in birds with unusual coloration. I know of 2 cases of peregrines that looked exactly like pure tundrius, but their parents had the typical appearance of the re-introduced population, which strongly resembles eastern anatum (but is not anatum; it’s an intergrade of the 7 subspecies). One of those tundrius look-alikes was from the Gulf Tower, quite a few years ago when the population was still small.

So, my best guess is that this bird is an adult peregrine in which recombination has resulted in homozygosity of some alleles from its pealei ancestors. And the downtown bird is fertile, inconsistent with it being any kind of hybrid.

It will be interesting to see what this year’s young look like when they molt into adult plumage. But unfortunately, we’ll never know.

— Paraphrased email from Art McMorris, 4 June 2023

What other clues do we have about this bird?
Art has so much experience with peregrines that he also said: “Earlier the brown bird was called the male, but the feet look female to me.”

Yo! Big feet?!

Dark adult peregrine at Third Avenue, 28 May 2023 (photo digiscoped by Kate St. John)

Just when I think I’ve got it all figured out, peregrines surprise me again.

(photos by Jeff Cieslak and Kate St. John)

Take Me To The Rescue Porch

Fledgling peregrine on the dog park windowsill (only 2 feet up), 5 June 2023 (photo by Leslie Mcilroy via Mark Catalano)

7 June 2023

At 6:30pm on Monday 6 June, Mark Catalano of Wildlife In Need Emergency Response was working dispatch in Central PA, making phone calls and sending texts and emails on behalf of a juvenile peregrine in a tiny dog park in Downtown Pittsburgh. The juvie needed assistance to be placed up high to start over on his first flight. Meanwhile Leslie McIlroy was in the dog park, protecting the bird from the visiting dogs.

Fledgling peregrine at the dog park on Third Avenue, 5 June 2023 (photo by Leslie Mcilroy via Mark Catalano)

Mark called the PA Game Commission but he knew it would be a long wait for a Game Warden. Since Mark is from Northumberland, PA he didn’t know any local peregrine contacts so he asked his wife to search the Internet for “Pittsburgh peregrine.” She found me, Mark sent me photos, and I told him about the Rescue Porch.

The Rescue Porch is a high balcony across the street at Point Park University’s Lawrence Hall. Another juvie had already tried it out this week, as seen by Diane Walkowski and Lori Maggio at 1:30pm on Sunday 4 June. (White arrow points to the bird.)

Juvenile peregrine calls from the Rescue Porch at Third Avenue, 4 June 2023, 1:50pm (photo by Lori Maggio)

Every year one or more fledglings ends up on the Rescue Porch. The Third Avenue ledge is so low and tucked away that fledglings land on the ground on their first flight when they don’t yet have the upper body strength to fly up and away.

Monday’s bird was stuck in a place I’d never heard of. It turns out that this narrow space under construction in 2021 became a tiny dog park with a tiny patch of grass. The yellow arrow points to a 2021 juvie who eventually landed in here. This year’s juvie hopped up to the low windowsill on the righthand wall, only two feet off the ground (photo at top).

Future dog park under construction on Third Ave, June 2021 (photo by Kate St. John)

Many thanks to Mark Catalano for starting the rescue and to Leslie McIlroy for guarding the bird until the Game Warden arrived three hours later.

Meanwhile, no news is good news. Sunday’s bird is out and about. Monday’s bird probably flew on Tuesday. Will the third youngster need a rescue too? Time will tell.

Click here for photos of the nest site and all three youngsters about to fly on 3 June.

(photos by Leslie Mcilroy via Mark Catalano of Wildlife In Need Emergency Response, Lori Maggio and Kate St John)

About To Fly At Third Avenue

4 June 2023

Peregrine falcons have nested in Downtown Pittsburgh since 1991 and though the players have changed they are very loyal to the territory. From 1991-2011 they nested at the Gulf Tower but since 2012, with three exceptions, they have nested at the back of a building facing Third Avenue. 2023 is their ninth nesting season at this site.

Yesterday morning I stopped by Third Avenue to see if any peregrines were visible and was lucky to see the entire family. Three youngsters perched at the ledge opening (photos at top) while their parents watched from above on the crossbars. The brown youngsters are exercising their wings and will fledge this week.

Downtown peregrine nest area as seen from Third Ave. Locations of birds noted in white. 3 June 2023 (photo by Kate St. John)

The adults have been a mystery. On 3 March Jeff Cieslak photographed an adult-plumaged pair: an unbanded female (not 16-year-old Dori who was banded) and a male who did not show his legs. When Jeff returned on 14 April he saw a nest exchange that appeared to be a male (unbanded in dark brown immature plumage) bringing prey to a female (banded & in adult plumage). The behavior told us who was who. Or did it?

Here are photos of the adults.

Adult-plumage bird on 18 May and 3 June 2023. Jeff re-checked his photos and saw that this bird has black/red bands and several viewers have remarked that the bird’s face is like Terzo’s. This is the male, Terzo.

Adult plumage peregrine at Third Avenue, 18 May 2023 (photo by Jeff Cieslak)
Adult plumage peregrine at Third Ave, 3 June 2023 (photo by Kate St. John)

Photos of the dark brown bird on 28 May and 3 June 2023 are more of a mystery. The flank stripes are horizontal so this is adult plumage. This dark brown unbanded bird is the female. More on her color in a future article.

Dark plumaged peregrine at Third Avenue Downtown, 28 May 2023 (photo by Kate St. John)
Dark plumaged peregrine at Third Avenue Downtown, 3 June 2023 (photo by Kate St. John)

Stop by Third Avenue in the next few days to see the youngsters fledge.

(photos by Kate St. John and Jeff Cieslak)

About To Fly

3 chicks in red-tailed hawks’ nest, Schenley Park, 28 May 2023 (photo by Charity Kheshgi)

31 May 2023

Spring nesting season is continuing apace. The first batch of baby robins is learning to fly and some are old enough to forage on their own. Raptor fledglings are not far behind.

On Sunday 28 May we watched three red-tailed hawk chicks in a nest under the Panther Hollow Bridge in Schenley Park. This species hatches in the order the eggs are laid, each one two days younger than the last. The chicks clearly show their age difference in Charity Kheshgi’s video. One chick is getting ready to fly, one is still fluffy, and the middle one is halfway between.

Red-tailed hawks’ nest, Schenley Park, 28 May 2023 (video by Charity Kheshgi)

At the Tarentum Bridge on Sunday afternoon, John English and I watched three peregrine chicks lounging on top of the nestbox while an adult “babysat” nearby.

Adult female peregrine watches her ledge-walking chicks at the Tarentum Bridge, 28 May 2023 (photo by John English)

At first we saw only three chicks but after we moved to a better viewing location the fourth was on the top of the box as well, exercising his wings.

Four peregrine chicks at Tarentum Bridge, 28 May 2023 (photo by Kate St. John)
Four peregrine chicks at Tarentum Bridge, 28 May 2023 (photo by Kate St. John)
One chick concentrates on exercising his wings (photo by Kate St. John)

And suddenly I saw him fly the length of the pier to the other end and back again to the top of the box! I have no photos of this feat but you get the idea. By today he may have fledged from the bridge.

All these birds are about to fly.

(photos by Charity Kheshgi, John English and Kate St. John)

Newly Found Peregrines’ Nest Near Brownsville, PA

Female peregrine clutching prey and shouting, West Brownsville Lane Bane Bridge, 26 May 2023 (photo by Jeff Cieslak)

30 May 2023

Last Wednesday, 24 May, Mark Vass drove down the Monongahela River valley looking for birds and checking bridges. In West Brownsville he found a peregrine perched under the US Route 40 Lane Bane Bridge. Mark’s checklist and photo set off a quest to find the nest (https://ebird.org/checklist/S139102470)

Jeff Cieslak made the trip on Friday 26 May and found the nest hole and a pair of peregrines carrying food to it. The female is peachy with heavy dots, the male is whiter. Neither bird is banded. (My male-female assessment is based on the tendency of mid-latitude males to be paler than females. Notice that both have the adult plumage trait of horizontal stripes on their flanks.)

Male peregrine, West Brownsville Lane Bane Bridge, 26 May 2023 (photo by Jeff Cieslak)
Male peregrine, West Brownsville Lane Bane Bridge, 26 May 2023 (photo by Jeff Cieslak)

Alyssa Nees and Fred Kachmarik visited on Memorial Day, 29 May, and counted a family of five — two adults, three chicks. Alyssa’s photos show an adult in the nest hole …

Peregrine inside the nest area on the Lane Bane Bridge, West Brownsville, PA, 29 May 2023 (photo by Alyssa Nees)

… and a chick clearly visible (red circle) with fluffy white top of head, feathered face and brown back. The arrow points to the tail of an adult watching from above.

Adult peregrine (arrow) and fluffy white head, face & brown back of nestling (circle) at Lane Bane Bridge, 29 May 2023 (photo by Alyssa Nees)

Fred’s photos of the chicks include an older chick and a fluffy young one:

Where are these peregrines located?

The Lane Bane Bridge, carries US Route 40 over the Monongahela River from West Brownsville, Washington County, to Brownsville, Fayette County PA. Its construction is very similar to the Graff Bridge at Kittanning, PA, which has its own nesting peregrines.

A truss structure spans the river and ends at a pillar on each side. As far as I can tell from the photos, the nest appears to be close to the pillar. So these birds are nesting in Washington County, PA.

Interestingly, when Google Street View cameras drove by on the West Brownsville side this month, the cameras “saw” a bird perched on the superstructure near the pillar. I’ll bet this dot is a peregrine.

Bird (probably peregrine) perched near on the Lane Bane Bridge over West Brownsville (screenshot from Google Street View)

Thanks and congratulations to Mark Vass, Jeff Cieslak, Alyssa Nees and Fred Kachmarik for finding and documenting this peregrine family.

If you’d like to see the birds yourself, Jeff provides a map.

Location of West Brownsville “scrape” at Lane Bane Bridge (screenshot from Google maps annotated by Jeff Cieslak)

p.s. Could there be another peregrine nest at the next bridge three miles away? Nope. The Mon-Fayette Expressway bridge is solid concrete. Click here to see a screenshot of the Mon-Fay bridge in Google Street View.

(photos by Jeff Cieslak, Mark Vass via eBird, Alyssa Nees, Fred Kachmarik via eBird, Wikimedia Commons and screenshots from Google Street View)