Juvenile and adult Cooper’s hawks, Frick Park, 14 July 2022 (photo by Charity Kheshgi)
25 July 2022
This April Charity Kheshgi and I noticed Cooper’s hawks nesting in Frick Park and wondered when their young would fledge. In “Cooper’s Hawk Nesting Questions” I concluded the young would fly by June 22-26 at the latest. They were even later than that because…
This month we checked on their progress every few days. On 3 July the pair had four thriving youngsters who were walking on branches and making short hops. (Not fledged yet?) By 8 July the young could fly but they refused to leave the vicinity of the nest.
All four were still there on 14 July, flying well and begging near the nest. “Feed me!” Their father baby-sat, above, while their mother was out hunting. The young were very alert, especially when they saw “mom” coming home.
Two of four juvenile Cooper’s hawks, Frick Park, 14 July 2022 (photo by Charity Kheshgi)Two juvenile Cooper’s hawks near their former nest in Frick Park, 14 July 2022 (photo by Charity Kheshgi)
July 14th was the last time we saw all six family members together. Five days later they had dispersed. The Cooper’s hawk family had grown up.
Merlins (Falco columbarius) are small fast falcons about the size of pigeons, though pigeons outweigh them. Like their peregrine cousins, merlins declined because of DDT and their population retracted into Canada’s boreal forest. After DDT was outlawed, they recovered slowly and in 1995-2014 began to take up residence further south. Some began nesting in towns and cities.
Four months later on 18 July Malcolm saw proof that they’d raised a family — a juvenile with parents at Chatham.
County record! Merlins are nesting in Pittsburgh!
Merlin family at Chatham University, juvenile in the center, 21 July 2022 (photo by Malcolm Kurtz)
Why Chatham?
Birds of the World, Merlin account explains: “Merlins do not build a nest and make few if any modifications to an old corvid or hawk nest. In cities, they nest in conifers in residential areas, school yards, parks, and cemeteries. High availability of safe nesting sites (corvid nests in spruces) and high prey abundance (house sparrows) appear to be two main reasons for urban populations of merlins.”
Yes, I’ve seen plenty of house sparrows in the merlins’ territory.
Merlin family at Chatham University, juvenile in the center, 21 July 2022 (photo by Malcolm Kurtz)
How long will the juvenile merlin hang around?
Again from Birds of the World, Merlin account, “Fledglings remain dependent upon adults and remain near nest sites for 1 to 4 weeks. They often hunt for dragonflies, which are abundant in July and August and may half-heartedly chase potential prey species or pigeons.”
Will the Chatham merlins be back next year? Perhaps nearby but not in the same nest. Merlins rarely use the same nest in two consecutive years.
There was excitement on Sunday 26 June when both eaglets at the USS Irvin bald eagle nest fledged at the same time. The eaglecam showed that when the first bird fledged, it knocked its sibling off the branch. Fortunately the second bird could still be seen on the eaglecam.
The article mentions that the eaglet will be unable to fly until next year. That’s because the flight feathers of bald eagles grow on a prescribed schedule rather than immediately upon feather loss.
In their first year of life eaglets grow their original flight feathers while in the nest, then wait until the following year to molt into Basic 1 plumage. The molt begins in the spring of their second calendar year and finishes with the tail feathers in late July–early August. This eaglet will have to wait a year to make its first flight.
(logo from USS Irvin Eaglecam, footage of the Double Fledge embedded from Pix)
Blackpoll warbler, Schenley Park, 22 May 2022 (photo by Charity Kheshgi)
23 May 2022
Six of us gathered at Schenley Park yesterday morning in perfect weather for a bird and nature walk. (The sixth is taking the picture.)
Great weather for an outing in Schenley Park, 22 May 2022 (photo by Charity Kheshgi)
First on the agenda was a look through my scope at the Pitt peregrines. Though we were half a mile from the Cathedral of Learning we could see one adult babysitting and two fluffy heads looking out the front of the nestbox. This is where the chicks were standing as we watched.
3 peregrine chicks at the Cathedral of Learning, 26 days old, 22 May 2022
Inside the park, a pair of red-tailed hawks is raising three chicks about the same age as the peregrines. We paused on our walk to watch them eat. Best views are from here.
Scroll through Charity Kheshgi’s Instagram photos to see our Best Birds including the blackpoll warbler pictured 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.
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.
Early yesterday morning the mother bald eagle at the USS Irvin nest in West Mifflin turned her eggs and revealed a pip. You can see the pip in the video below.
Les Leighton had his camera set up at Canada’s Vancouver harbor when a drama played out in front of him. A gull zipped by with both a bald eagle and peregrine falcon pursuing it in flight. What was it about that gull that attracted two predators at the same time?
Watch the chase and notice the difference between the eagle’s and peregrine’s hunting techniques. Why did both of them give up?
Six of us braved the drizzle yesterday morning at Duck Hollow and were rewarded with an exciting visit from one of the Hays bald eagles. Connie Gallagher captured part of the action in photos.
Five of 6 participants at the Duck Hollow outing, 20 March 2022 (photo by Kate St. John)
It all began with two herring gulls on the mud spit, manipulating a large fish.
Two herring gulls with a big fish, 20 March 2022, 8:45am (photo by Connie Gallagher)
The gulls hadn’t made much progress opening the fish when they saw the male Hays bald eagle flying upriver toward Duck Hollow. All the waterbirds could tell the eagle wanted that fish. The ducks stayed put, the gulls quickly stashed the fish and flew up calling and complaining.
The eagle made three dropped-talon passes at the fish but it was too hard to grab in flight. Meanwhile the gulls divebombed him and chased him every time. That fish was stashed so tightly that the eagle would have to land to get it. But the gulls were relentlessly annoying.
Finally the eagle left and the gulls resumed their meal, watched by a crow.
Herring gulls resume their meal, 20 March 2022, 10am (photo by Connie Gallagher)