Let’s take a break from birds of prey. Here’s a story about another species.
Great blue herons (Ardea herodias) are returning to Pennsylvania and gathering at their rookeries to court and nest.
This video from Florida shows their elegant gestures and courtship rituals as they build their pair bond.
An added bonus on the video are the bird sounds in the background. Listen and you’ll hear sandhill cranes, boat-tailed grackles and American coots.
(video by Filming Florida on YouTube)
Red-tailed hawks who live in the city are habituated to people. They go about their business hunting squirrels and eating pigeons — even on the ground — while we walk by or stand and gawk.
This spring a pair of red-tailed hawks is building a nest on Pitt’s campus. They experimented with a tree on the Cathedral of Learning lawn but by Tuesday it was clear they’d chosen the top of a large London plane tree next to the Student Union.
It’ll be interesting to see what happens next.
Will the hawks ultimately use this nest? Will Pitt’s peregrines forbid them from gaining altitude so close to the Cathedral of Learning? (I’ve already seen Terzo hammer one of the hawks.) Will people notice the nest at all?
If the nest was close to the ground, the red-tails would become nervous about us walking below it and might threaten us to chase us away. This rarely happens but it’s memorable, as in this incident at Fenway Park eight years ago –> Red-tails Close to Home.
The red-tail nest on Pitt’s campus is way too high up for that. The hawks and the peregrines will have to work out their boundaries but we ground-based humans are of little interest to them.
And that’s as it should be.
(photo by Bill Barron)
6 April 2016:
Now that we’ve had a complete changeover of adult peregrines at the Cathedral of Learning (as of 6 April 2016) we need new guidelines for telling apart the male and female.
Here are some clues for identifying Terzo and Hope when viewing them on the nestcam. The most reliable clues are listed first.
1. Faces: Examine the photos above for these clues. Terzo is at top, Hope on bottom.
Terzo: The area between Terzo’s malar stripe (moustache) and the dark gray of his nape (back of his neck) is bright white with a small black spot at the top. His “necklace” is long and thin and almost reaches the bottom of his malar stripe. Some people say the white area framed by gray looks like a heart.
Hope: The area between Hope’s malar stripe and nape is “muddy” with gray feathers. She has almost no “necklace.”
2. Band colors: Terzo’s color band is Black over Red, N/29. Hope’s is Black over Green, 69/Z.
3. Plumage contrast on back: Adult male peregrines usually have paler gray backs than the females. See the photos below: Terzo on top, Hope at bottom.
Terzo: His head and wingtips are darker than the feathers on his back.
Hope: Her feathers are more uniform in color.
4. Pale Stripes on flanks and legs versus Bold Stripes:
Terzo is a bright white bird and this shows on his legs and flanks. His striped feathers are more white than black.
Hope’s dark stripes are much more obvious.
And now, a quiz. Can you figure out who is who in this photo? Who’s at the back? Who’s in front? What clues did you use?
(photos from the National Aviary falconcam at Univ of Pittsburgh)
Spring started early but this week’s cold snap has put everything on “Pause.” From 22 degrees above normal on March 31 to 7 degrees below normal on April 3, we’ve seen it all.
Despite that, this phenology of What to Look For in Early April should be a good one.
How much of the list did you see in March?
So much is yet to come!
p.s. Friends of mine saw yellow-throated warblers (pictured above) last weekend in Morrow-Pontefract Park, Edgeworth.
(photo of a yellow-throated warbler by Chuck Tague)
(If you subscribe to PABIRDS you saw this news over the weekend.)
After the great horned owl fledgling was rescued in Schenley Park on Tuesday March 29 and an adult was seen nearby on Thursday morning, I made it my mission to find the nest. At first I came up empty. There were no big stick nests in any of the hillside trees.
Then, late Friday afternoon I took another look at the underside of the Anderson Bridge.
Faintly through the trees I saw two owlets walking on a girder!
On Saturday I brought my scope and discovered that the “branching” owlets and their mother were quite visible from the Junction Hollow Bike Trail below the bridge. Here are two (lousy!) photographs I took through my scope.
Above, mother owl and one owlet pose on the girder. Below, the second owlet is perched just below the nest. Later he flew from girder to girder and landed near his mother. The blue box highlights him in the washed-out photo.
On Sunday I visited the trail again and Nathan Mallory used my scope to take this photo of the two owlets sleeping. You can see their stick nest above them on the lattice.
So there were three owlets in this nest. The first is in rehab. The other two will probably fly soon.
p.s. As you can see, the Anderson Bridge is very rusty! It will be completely replaced in a few years, after the Greenfield Bridge is done.
(photos by Kate St. John and Nathan Mallory)
This morning Terzo kept four eggs warm at the Cathedral of Learning peregrine nest while Hope left to eat breakfast.
Here he is showing off the sharp contrast between his gray back and his black head and wing tips. Hope’s feathers do not contrast as much.
Does this mean incubation has begun? Terzo’s action is a good indication that this may be the first day of incubation, but the pair’s activities will tell the tale. We’ll know for sure when they’re on the eggs nearly 24×7.
How long until the eggs hatch?
Incubation lasts about 33 days. If today is the first day of incubation, watch for hatching around May 6. (Note that hatch date predictions are never exact!)
(photo from the National Aviary snapshot camera at Univ of Pittsburgh)
This afternoon at about 4:35pm, Hope laid her fourth egg of the season.
Her first three eggs were fathered by her deceased mate, E2, whose body was found on March 16. This fourth egg arrived 15 days later and is undoubtedly fathered by her new mate Terzo.
Will she lay more eggs? We don’t know.
Will she begin incubation now? We’ll have to wait and see.
Only Hope knows the answers to these questions.
Stay tuned on the National Aviary falconcam at University of Pittsburgh to find out.
UPDATE:
Here’s a video captured by Peter Fullbrandt showing Hope laying the egg. Skip to the 5:00 mark and you will see her breathing with her beak open for about 30 seconds. When she raises her tail (at the 5:33 mark) it’s just after she’s laid the egg, though you cannot see it. We waited for an hour for her to move off the eggs so we could count four.
(photo from the National Aviary snapshot camera at Univ of Pittsburgh; video capture by Peter Fullbrandt)
The flowers are ahead of schedule and so are some migratory birds. This week in Schenley Park I found four new arrivals.
Brown creepers (Certhia americana) spend the winter in the central and southern U.S. so they know about our warm weather and can decide to migrate early. I saw several brown creepers and heard their high pitched, squeaky song along the Bridle Trail on Thursday.
Audio Player“Brown Creeper (Certhia americana nigrescens)” from xeno-canto by Mike Nelson. Genre: Certhiidae.
Two very tiny birds, smaller than chickadees, arrived on Tuesday. It’s unusual to see them together.
Golden-crowned kinglets (Regulus satrapa), at left below, have a winter range similar to the brown creeper’s and usually migrate through before their ruby-crowned cousins show up. I found both birds on March 29 when I heard the ruby-crowned kinglet singing “Stay away!” as the golden-crowned chased him. I’ve never seen these two species fighting!
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Ruby-crowned kinglets (Regulus calendula) spend the winter in the southern U.S. and even in eastern Pennsylvania but they’re a big deal here. An appearance on March 29 is two weeks earlier than I expect them.
Here’s the ruby’s song and, at the end, the “chack” he makes when annoyed.
Audio Player“Ruby-crowned Kinglet (Regulus calendula)” from xeno-canto by Hal Mitchell. Genre: Regulidae.
On Tuesday I heard a lone chipping sparrow (Spizella passerina) along the Bridle Trail but couldn’t find him for two days. He was hanging out with a flock of dark-eyed juncoes. Bob Machesney says that in the North Hills the dark-eyed juncoes are gone before the chipping sparrows arrive. This solo bird isn’t playing by the rules. 
Here’s the chipping sparrow’s song:
Audio Player“Chipping Sparrow (Spizella passerina)” from xeno-canto by Martin St-Michel. Genre: Emberizidae.
Watch for the first three birds in the days ahead. Only the chipping sparrow will stay to nest in Schenley Park.
(all photos by Steve Gosser)
By now it’s clear that the two nestlings in the Hays bald eagle nest are doing well but many of you wonder about the third unhatched egg. What will happen to it? Why hasn’t it hatched?
One unhatched egg is a fairly common occurrence in the nests of many birds. Some eggs are not fertile, some have developmental issues. There are many reasons. Birds often lay more eggs than actually hatch, perhaps as insurance against this rather common eventuality.
Among bald eagles, the need to brood the young for a week allows ample opportunity for remaining eggs to continue incubation and eventually hatch. While the adults brood the nestlings they can hear if an egg has a live bird in it because baby birds make peeping and hammering sounds inside the egg a day or more before hatching. Eggs that aren’t going to hatch are silent.
What happens to unhatched eggs? Birds are not emotional about them. When it’s obvious an egg won’t hatch, the family moves it around the nest for their convenience. In bald eagles’ nests it may eventually become buried under debris along with the remains of dinner.
What if it hatches now, more than a week late? Here’s the answer from the Audubon Society of Western PA on their Bald Eagles of Western PA Facebook page on March 30, 9:39pm:
“We’ve gotten many questions about the last egg in the Hays nest. At this point there are no good options for what can happen with that egg. Perhaps the egg is just not viable and will not hatch. But if the egg should hatch (there is still a remote possibility) the newly-hatched eaglet would have a difficult time thriving. It would be more than a week younger than its siblings, meaning it would be much smaller and have a hard time competing for available food. While nobody likes to hear this, it is nature and if we didn’t have a webcam focused on the nest, we wouldn’t even know it was happening. All we can do now is wait and see how it plays out…and be thankful for the two vibrant eaglets that we do have in Hays.” — eagles.aswp.org
The text above gives you a hint.
Knowing bald eagle family life as I do, my hope is that the third egg never hatches.
UPDATE, 2 April 2016, 7:36am: See below for a press release about Egg#3 from the Audubon Society of Western PA.
Audubon Society of Western Pennsylvania Statement on the Remaining Egg in the Hays, PA Bald Eagle Nest
For immediate release, April 2, 2016.
There is one unhatched egg remaining in the Hays, PA Bald Eagle nest. The egg has gone one week past the typical 35 day incubation period and at this time, the adult eagles are no longer actively incubating the egg. Audubon believes that the egg is not viable and will not hatch.
While we will never know for certain why this egg did not hatch, it’s possible that it was not fertile from the start. An infertile egg cannot develop into an eaglet and the egg would thus be deemed non-viable. It’s also possible that something went wrong developmentally within the egg after it was laid.
Across the state in Hanover, it appears that their local Bald Eagles also have an egg that is not going to hatch. We do not believe that there is any connection between the non-hatchings in Hanover and Hays—it’s nothing more than a coincidence. Last year, both sides of Pennsylvania had abnormally cold winters, which we believe was one of the factors that led to an unsuccessful breeding season for our Pittsburgh Bald Eagles. But in 2015, the Hanover Bald Eagles raised and fledged young, while facing the same cold temperatures. Before webcams were pointed on these nests, we did not know what was happening inside of them. Today we can see nature at work—both the good and the hard, sometimes uncomfortable reality of it.
The positive news is that the Hays Bald Eagles have two healthy and vibrant eaglets in their nest—eaglets that are approaching two weeks old and growing every day. We look forward to watching their continued growth and development, and eventual fledging from the nest in early summer. The Hays Bald Eagles have successfully hatched six eaglets: one in 2013, three in 2015, and two in 2016. The unhatched egg will eventually be broken through activity in the nest—parents and eaglets moving around. The egg, like the shells of the hatched eaglets, will eventually become invisible within the nest. An image of the female Hays Bald Eagle and two eaglets is attached.
Watch Pittsburgh’s eagles at eagles.aswp.org. For additional information on the Hays and Harmar Bald Eagles, please visit our Facebook page, www.facebook.com/pittsburgheagles, where daily updates on both nests are posted. The Harmar Bald Eagles’ first egg is expected to hatch on our around April 13.
(photo from Hays eaglecam)
p.s. Celebrate bald eagles this weekend at Audubon Society of Western PA’s Beechwood (Allegheny County) and Succop (Butler County) locations with a free “Eagle Egg” Hunt and other activities.
On Saturday, April 2 at Beechwood: Egg hunts at 11 am, 12 pm, and 1 pm – bring a bag to collect eggs! Parking is at Fairview Elementary School, 738 Dorseyville Road. Shuttles will bring visitors to Beechwood Farms Nature Reserve. Please allow time for the shuttle to transport you to the event. The Pennsylvania Game Commission and PixController will be onsite, as well as a local chicken expert who will bring baby chickens! There will also be games, crafts, and activities. Register today for Beechwood!
On Sunday, April 3 at Succop: Egg hunt begins at 12 pm – bring a bag to collect eggs! Then participate in eagle-themed games, crafts, and activities. Register today for Succop!
Or call (412) 963-6100 to sign up.
For months we thought the old red-tailed hawks’ nest under the Homestead Grays Bridge was abandoned, but last Sunday John English discovered it is very much occupied — by a great horned owl. John posted the photo above in the Duck Hollow Facebook group with this diagram of its location.
Dana Nesiti (EaglesofHaysPA) stopped by yesterday and got this beautiful shot of the mother owl. In this species, only the females incubate and brood. Father owl perches nearby during the day.
Dana watched for 45 minutes and was rewarded with a glimpse of the tiny owlet — the round white head at center-right of the nest. I’m no expert but my guess is this owlet hatched 1-2 weeks ago.
Meanwhile, not far away….
At midday on Monday Cathy Bubash posted a comment on my blog that there was an injured owl on the road at Schenley Park’s Anderson Playground. We traded email addresses and Cathy sent photos. Oh my! It’s not an injured adult. It’s a fledgling great horned owl!
He’s old enough to fly, though he isn’t very good at it. He appears to be about 8 weeks old.
I visited the area at 4:30pm and found the owl safely perched on a hillside tree below the playground. His parents could find and feed him overnight … but where were they?
In all my visits to Schenley Park I’ve never encountered a great horned owl and never seen a nest. I rechecked two abandoned red-tailed nests on nearby bridges. Nothing.
On Tuesday morning the owl was back on the asphalt at Anderson Playground so Public Works employees wisely called the PA Game Commission who collected the owl and delivered it to ARL Wildlife Center for evaluation.
It’s a good thing this owl was rescued. He’s not injured but he is emaciated. Did he have parents in Schenley Park?
Based on his age — two months older than our local owlets — I had a theory that he hatched in the South, perhaps the Carolinas, and was brought to Pittsburgh by someone who dumped him at the secluded end of the playground when he got too big.
But my theory was wrong! After publishing this blog I learned that a Public Works employee saw a great horned owl this morning at 6:45am near the Anderson Bridge.
In any case, while this owl fattens up he will have a good foster mom at ARL. Martha the great horned owl will teach him everything he needs to know.
(photos by John English, Dana Nesiti, Cathy Bubash and Kevin Wilford)
Event: This Sunday, April 3, 4:00-6:00pm, you can meet owls from the ARL Wildlife Center at their fundraiser at the Galleria of Mount Lebanon. Click here to register.
p.s. Ravens are rare in the City of Pittsburgh but I saw a pair poke at the Homestead Grays Bridge nest on February 18. They were agitated. Now I know why. The owl was probably in the nest and just beginning incubation. Ravens hate great horned owls.