Hatching at the Cathedral of Learning peregrine nest begins next week (or sooner!) but we don’t know what day it will be. Since a chick can take as long as 72 hours from hammering to hatch, today is not too soon to start Pip Watch at the Pitt peregrine nest.
We will not be the first to learn that a chick’s been busy. His parents can hear his hammering and his vocalizations inside the egg. When Morela traded incubation duties with Ecco recently, I saw her fidget over the eggs for longer than usual and vocalize softly. If she heard a chick “peeping” inside the egg her own chip calls would stimulate the chick to vocalize in return. They can have a “conversation” through the shell.
Want to know more about the process? Check out this vintage article. Watch for a pip at the links above.
On 12 April my friend Charity and I saw a Cooper’s hawk building a nest. Yesterday we saw an adult in the nest, incubating. We wondered about the process: When did nest building end? When did incubation begin? Does the male share incubation duties? How long before the eggs hatch?
The answers are fascinating because Cooper’s hawks don’t follow the expected rules. In the quotes from Birds of the World, below, did you know? …
Cooper’s hawks are a “common backyard breeding bird in cities of all sizes.”
Male Cooper’s hawks do most of the nest building. The female stops by occasionally to check on his progress and helps a bit, especially at the end.
Nest-mates have multiple genetic fathers. “Cooper’s Hawks exhibit high rates of extra-pair paternity involving both territorial and especially non-territorial floaters.”
Only the female has a brood patch. She does most of the incubation. The male takes over for short periods while she eats.
The female broods the chicks for two weeks, about twice as long as peregrines do.
Further details from Birds of the World help answer our questions about the nest:
Nest building takes 2 weeks.
Eggs are usually laid in the morning at 2 day intervals (occasionally 3 days) for a total of 3-5 eggs.
Incubation begins after the 3rd egg and lasts 34 days. The first 3 eggs hatch on the same day; the 4th and 5th eggs laid usually hatch 1 day later, occasionally up to 3 days later.
The young leave the nest at about 30 days (males) to 34 days (females), although able to clamber short distance in nest tree 4–5 days earlier.
The earliest schedule would be: Nest completion on 12 April, female laid 3 eggs 12-16 April, incubation began 16 April, hatching on 20 May, young leave the nest 19-23 June.
The latest schedule would be: Female began incubation 19 April, hatching on 23 May, young leave the nest 22-26 June.
I plan to stop by occasionally to see what’s up. The excitement will start in late May.
Meanwhile, see photos of a Cooper’s hawk family nesting in a backyard in this vintage article from 2017.
In the spring starlings sing their wiry scratchy songs, punctuated with puttering sounds and embellished with mimicry of other birds. They usually copy their neighbors but like to add the coolest sounds of migrating birds. Starlings tell us what they heard in the past few days and nights.
Have you heard a killdeer call from a city housetop? It’s a starling telling you he heard a killdeer recently. Other examples include.
Mimicking an eastern meadowlark.
Mimicking the Eurasian oystercatcher in Scotland, the starling “calls from a roost in a building after a night of heavy passage of migrant oystercatchers.”
Mimicking his neighbors in Toronto, including American goldfinch and red-tailed hawk at 0:53 – 1:07. He’s so good at it that he fooled my Merlin Bird ID app.
The Future as told by Starlings
“You will see a raptor overhead.”
Starlings make a wiry spitting alarm-call that means “Danger From The Air!” If you hear this call, look up to see a raptor. The starling tells your future. (Note: In this recording from Colorado, the robin-like song in the background is a black-headed grosbeak.)
Bonus Bird ID: The Virtuoso For those of you familiar with birdsong in southern California, this starling in San Diego County will give you a run for your money! It even fooled the Merlin Bird ID app. The recording’s description says. “Much mimicry including Northern Flicker, Nuttall’s Woodpecker, Mountain Quail, Mountain Chickadee, California Towhee, Acorn Woodpecker, Killdeer, and perhaps American Kestrel and Common Poorwill.
(photo from Wikimedia Commons, audio embedded from Xeno Canto. Click on the caption links to see the originals)
Incubation is boring, but hatching begins next week!
Of the eleven sites we’re monitoring in Southwestern PA, six of them are definitely or likely to be incubating. Right now it’s boring at all the sites but excitement is coming soon. Hatching begins next week at Pitt. The others can’t be far behind.
Morela and Ecco’s first three eggs have been incubating since 23 March and are due to hatch on/about 26 April, the 4th egg around 28 April, and the much later 5th egg (the whitish one) around 3 May.
All the dates are guesses. Watch the Cathedral of Learning nest on the National Aviary falconcam to see if I’m right.
Meanwhile, get a flavor of how boring incubation is in this Day-in-a-Minute video from 16 April. Can you tell when Morela and Ecco trade places? Morela is the bigger bird.
Peek-a-boo! Did you see that whitish egg make an appearance?
Downtown Pittsburgh:
Downtown peregrine incubating at nest on Third Avenue, 17 April 2022, 2:38pm (photo by Kate St. John)
I set up my scope on Mt. Washington near the Monongahela Incline on 17 April to look into the nest on Third Avenue. See that small black and white spot on the left? It moved. It’s a bird. The Downtown peregrines are incubating. I have no idea when the eggs will hatch.
Ambridge-Aliquippa Bridge, Ohio River: No news since 8 March 2022.
Sewickley Bridge, Ohio River:
Peregrines just after mating at the Sewickley Bridge, 17 April 2022 (photo by Jeff Cieslak)
Mystery at Sewickley! We thought this pair was incubating eggs but Jeff Cieslak saw them mating on 17 April. Was there a changeover in one of the pair? Did the nest fail? Were they not incubating after all? Jeff’s visits and pictures will solve the mystery some day.
Eckert Street / McKees Rocks Bridge area, Ohio River:
Peregrine at Eckert Street, 18 April 2022 (photo by Jeff Cieslak)
Jeff Cieslak continues to see the male and female trading off at the nest, most recently on 18 April. Incubation is definitely underway at Eckert Street.
Westinghouse Bridge, Turtle Creek:
Male peregrine takes off at Westinghouse Bridge, 10 April 2022 (photo by Dana Nesiti)
Incubation continues at the Westinghouse Bridge. Dana Nesiti saw a nest exchange on 16 April.
62nd Street Bridge / Aspinwall Riverfront Park, Allegheny River: No news since mid-March.
Tarentum Bridge, Allegheny River:
View of Tarentum Bridge nestbox area, June 2018 (photo by Amber Van Strien)
From a distance Dave Brooke can usually see the incubating adult in the nestbox at Tarentum Bridge, most recently on 10 April.
Graff Bridge, Rt 422, Kittanning, Allegheny River: No news since 16 March.
Speers Railroad Bridge, Washington County, Monongahela River: No news since February.
Trees and wildflowers are blooming. New birds come to Pittsburgh on every south wind. I expect gray catbirds (Dumetella carolinensis) will back in time for this outing. Will we hear one? Will we see him before he hides? I hope so.
Dress for the weather and wear comfortable walking shoes. Don’t forget your binoculars.
This event will be held rain or shine, but not in downpours or thunder. Check the Events page before you come in case of cancellation.
Hope to see you there.
p.s. If the birding is good I’ll give an option to continue until 11a.
(photo from Wikimedia Commons; click the caption to see the original)
Fancy daffodils at Phipps Conservatory’s Spring Flower Show, April 2022 (photo by Kate St. John)Serrated tulip petals, Phipps Conservatory’s Spring Flower Show, April 2022 (photo by Kate St. John)Spring wreath, daffodils and lilies, Phipps Conservatory’s Spring Flower Show, April 2022 (photo by Kate St. John)
Harbinger of spring, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
16 April 2022
Yesterday’s warm and sunny weather brought out woodland flowers that were waiting bloom. I found a good selection at Raccoon Creek State Park Wildflower Reserve in Beaver County, PA.
Four flowers were at their peak:
Harbinger of spring (Erigenia bulbosa), only 5-15 cm (2-6″) tall, is one of the first to bloom.
Spring beauty (Claytonia virginica) put on a show because the sun was shining.
Spring beauty, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
Chickweed (Stellaria sp.) was a puzzle without my Newcomb’s Guide. Which one is this? To me the petals look too long for common chickweed, too short for great/star chickweed but the lower leaves have long stalks which says “common” to me.
Chickweed, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
Trout lilies (Erythronium americanum) are a challenge to photograph because they face the ground.
Trout lilies, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
Other plants had one or two representatives while the rest waited to flower soon:
Cutleaf toothwort, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
Small-flowered crowfoot (Ranunculus micranthus), with leaves shaped like crows’ feet, is a member of the Buttercup family. Its small flower can be inconspicuous.
Small-flower crowfoot, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
Virginia bluebells, Raccoon Wildflower Reserve, 15 April 2022 (photo by Kate St. John)
Unfortunately yesterday’s gusty winds presaged today’s rain and colder temperatures for the week ahead. (Snow in the sky on Tuesday?!) The flowers at Raccoon may be delayed again.
Meanwhile weeds will not be phased by the change in weather. Look at the sidewalk’s edge to find bird’s-eye speedwell (Veronica persica), a native of Eurasia. I found this one near the feeders at Frick Park. Bird’s eye indeed!
Bird’s eye speedwell, Frick Park, 13 April 2022 (photo by Kate St. John)
Meanwhile in southwestern Pennsylvania, great horned owls (Bubo virginianus) laid eggs in January/February and hatched young around the time of this video. Keep an eye out for activity above. As the owlets grow up their nests will become more obvious, even during the day.
American elm, flowers becoming seeds in April, Homewood Cemetery (photo by Kate St. John)
14 April 2022
Have you been sneezing this week in Pittsburgh? Are your eyes itchy and watery? Pollen season just began and I can tell you which trees started it.
Pittsburgh is a deciduous place so we’re not contending with pine pollen. Instead we have wind pollinated deciduous trees that bloom before leaf out so their pollen will move freely in the forest.
When our landscape looks like this there’s pollen in the air.
The first to bloom are elms and maples.
American elms (Ulmus americana) are 100% wind pollinated and insure they don’t self-pollinate by producing female flower parts before the male parts mature. By the time the flower dangles in the wind the female parts are hidden.
The structure of sugar maple flowers (Acer saccharum) shows they’re designed for wind pollination.
Red maple flowers (Acer rubrum) are more discrete, pollinated by both wind and bees.
Red maple flowers (photo by Kate St. John)
Yesterday the temperature was warmer outside than inside so I opened the windows to pull in warm air. This morning my husband’s eyes are itchy. Uh oh. I raised the indoor pollen count. Mistake!
Spring green? Tree flowers! Ahhhh cho!
Blooming deciduous trees, Schenley Park (photo by Kate St. John)
p.s. This spring is off to a slow start so we started sneezing later than last year. 😉
In spring a change occurs in mourning dove behavior as large flocks we see in winter disperse to nest. Some flocks move north while locals break up into couples and fan out to choose a territory.
It is hard to notice when the change occurs so I graphed my eBird count of mourning doves (Zenaida macroura) in Frick and Schenley Parks, January 2021 through 9 April 2022.
My eBird counts of mourning doves in Frick & Schenley, 1 Jan 2021 through 8 April 2022 (data from Kate St. John)
The change is pretty dramatic. Just 1-5 birds from March through September, then over 40 December through February. The largest flocks were at the Frick Environmental Education Center where they sunned in the trees above the feeders. 100 mourning doves in January!
This year the count dropped below 10 in early March as they paired up. Some pairs maintain their bonds throughout the winter. Others get to know each other in the spring.
On territory the male visits potential nest sites and calls to his mate to inspect them. She gets to choose. (His nest call is 3 notes like this).
According to Birds of the World: To build the nest he brings small twigs, etc. which he delivers to her while standing on her back(!) She arranges them around her while using her body to form a simple bowl. Nest building usually takes 7–10 hours spread over 2–4 days.
The loosely built nest looks messy. Sometimes you can see through it from below.
And in October mourning doves gather in flocks again. The process starts over from flocks to nests.
UPDATE 13 April 2022: Today at Frick Park I talked with someone who has a mourning dove nest in their yard while 16 mourning doves hung out near the feeders. Flocking and nesting were simultaneous today.
(photos from Wikimedia Commons; click on the captions to see the originals)
