Archive for the 'Nesting & Courtship' Category

Apr 03 2016

Has Incubation Begun?

Terzo on four eggs at Pitt (photo from the National Aviary snapshot cam at Univ of Pittsburgh)

Terzo on four eggs at Pitt (photo from the National Aviary snapshot cam at Univ of Pittsburgh)

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)

 

12 responses so far

Apr 02 2016

Four Peregrine Eggs at Pitt!

Hope with 4 eggs at the Cathedral of Learning nest, 2 April 2016 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Hope with 4 eggs at the Cathedral of Learning nest, 2 April 2016 (photo from the National Aviary falconcam 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)

8 responses so far

Apr 01 2016

What About Egg #3?

Two nestlings watch as parent bald eagle returns to the Hays nest (photo from Hays eaglecam)

Two nestlings watch as parent bald eagle returns to the Hays nest (photo from Hays eaglecam)

 

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.

ASWP_logo

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.

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Mar 31 2016

A Tale of Two Owls

Great horned owl on nest under the Homestead Grays Bridge, 27 March 2016 (photo by John English)

Great horned owl on nest under the Homestead Grays Bridge, 27 March 2016 (photo by John English)

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.

Location of nest under Homestead Grays Bridge (photo by John English)

Location of nest under Homestead Grays Bridge (formerly called the Homestead High Level Bridge) as seen from Red Robin at The Waterfront. Duck Hollow is on right, across the river (photo by John English)

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.

Great horned owl on nest under the Homestead Grays Bridge, 30 March 2016 (photo by Dana Nesiti)

Great horned owl on nest under the Homestead Grays Bridge, 30 March 2016 (photo by Dana Nesiti)

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.

Great horned owlet in nest under Homestead Grays Bridge, 30 March 2016 (photo by Dana Nesiti)

Great horned owlet in nest under Homestead Grays Bridge, 30 March 2016 (photo by Dana Nesiti)

 

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!

Great horned owl fledgling, Schenley Park, 29 Mar 2016 (photo by Cathy Bubash)

Great horned owl fledgling, Schenley Park, 29 Mar 2016 (photo by Cathy Bubash)

He’s old enough to fly, though he isn’t very good at it. He appears to be about 8 weeks old.

Great horned owl fledgling in flight, Schenley Park, 29 Mar 2016 (photo by Cathy Bubash)

Great horned owl fledgling in flight, Schenley Park, 29 Mar 2016 (photo by Cathy Bubash)

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.

Great horned owl fledgling rescued at Schenley Park by PGC, 29 March 2016 (photo by Kevin Wilford)

Great horned owl fledgling rescued at Schenley Park by PGC, 29 March 2016 (photo by Kevin Wilford)

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.

9 responses so far

Mar 25 2016

Exciting Peregrine Courtship At Pitt

Hope perches at the front of the nest, pre-dawn, Fri 25 March 2016 (photo from the National Aviary snapshot camera at Univ.of Pittsburgh)

Hope perches at the nest, pre-dawn, Fri 25 March 2016 (photo from the National Aviary snapshot camera at Univ.of Pittsburgh)

What an exciting day we had yesterday, the first full day of a new male peregrine at Pitt!

Many of you watched the falconcam but all the action was in the air.  Of course!  Peregrines are famous for top speed flight so naturally they show off their talents in courtship.

Six (and more) of us watched from vantage points in Oakland throughout the day and kept each other up to date on the latest activity.  The male’s flight displays were breath taking.

A male peregrine’s first priority is to claim and secure the territory. The new guy made all the right moves: kiting above the Cathedral of Learning, racing across and around the “cliff” face, ostentatiously stooping on prey, and attacking other predators.  The local red-tailed hawks took the brunt of his ire. They may have to reconsider their nest location in a tree next to the Cathedral!

Hope and her new mate were conspicuous when they perched.  They even mated on the lightning rod, something I hadn’t seen since the days when Dorothy was a younger bird and E2 was new to the site.  It’s the ultimate signal that “This cliff is ours!”

The male rarely perched but when he landed above the nest, Hope bowed and ee-chupped.  Here’s where he is when she does that:

New male perched above the nest at the Cathedral of Learning, 25 March 2016 (photo by John English)

New male perched above the nest at the Cathedral of Learning, 25 March 2016 (photo by John English)

And … when you hear Hope shouting before dawn (above) she’s making a sound like the begging call.  Peregrine males must provide food for their mates during egg-laying, incubation and brooding. The first food delivery is usually at dawn.  By calling like this Hope is reminding him of his obligations.  She is one loud bird!

Read more here about the details of peregrine courtship in this article:  All The Right Moves.

 

Your Questions:  I love to answer your questions but I cannot respond to redundant ones.  Questions about Hope’s eggs are answered at this blog post and in the comments which follow it.  Please click the link and read the entries before posting a redundant question.

Hope’s loose feather:  The feather is not a problem. It will fall out eventually.  In the meantime we’ve found it useful for telling the difference between Hope and the male in flight.  (Hays bald eagle observers can tell you they use a similar feather trait to identify the eagles at Hays.)

 

(top photo from the National Aviary snapshot camera at Univ of Pittsburgh. photo of male by John English)

UPDATE: The male came to the nest this morning, March 25, and we captured photos of his bands: Black/Red N/29.  Art McMorris, PA Game Commission Peregrine Coordinator, is researching the bird’s origin.  He says it will take some time (maybe days) because the band is not in the databases. Art is making phone calls.  Please be patient!  (Remember, this is Easter weekend so the person who knows the answer may be on vacation.)

39 responses so far

Mar 24 2016

High Hopes!

Last night after sunset, viewers of the Cathedral of Learning falconcam heard a peregrine calling off camera and Hope began to “ee-chup” and bow at the nest.  This is courtship behavior! Hope has found a potential mate.

In the video excerpt above you’ll hear a peregrine wailing off camera as Hope bows and calls, asking him to join her at the nest.

The episode began at 7:53pm and lasted at least 6 minutes.

We don’t know if her potential mate spent the night on the Cathedral of Learning. If he isn’t yet comfortable with the building he may have roosted elsewhere. (Remember, the place is all new to him. He will be cautious at first.)

This morning Hope called very loudly from 6:47 to 6:51am, “Hey! Where are you?”  Then she left the nest.

Don’t worry if Hope is not at the nest much in the coming days.  Peregrine courtship requires many spectacular aerial displays.  That’s how the two birds get to know each other.

Watch and listen to the falconcam for more peregrine “conversations.”  We’ll know their courtship has reached a deeper level when we see both peregrines bowing at the nest.

We have high hopes that she’s found a mate.  🙂

 

p.s. Click here and scroll down to the Courtship section to learn more about peregrine courtship displays.

(video from the National Aviary falconcam at Univ. of Pittsburgh captured from WildEarth.tv archives)

p.s. Since I posted this article Hope and the new male have been seen mating three times! Woo hoo!

IF YOU ARE AT PITT, DO NOT ATTEMPT TO GET CLOSE TO THESE BIRDS. Peregrines view humans as their enemies & will leave the area if they think we are too close. Hope & her mate are so new to Pitt that they may be frightened away by seeing you staring at a window.

54 responses so far

Mar 23 2016

Second Egg Hatched at Hays Eagle Nest


Second egg hatches at Hays bald eagle nest, 22 March 2016, 9:40pm

 

Peregrine news has been so intense lately that I missed telling you about Pittsburgh’s first eaglet of 2016 … and now there are two nestlings at the Hays bald eagle nest.

Here’s a roundup of Hays nest news from first hatch on Monday to last night’s second hatch.  There’s one egg still in the nest.

1. First egg hatched on Monday March 21 at 12:37 am (just after midnight).  See video below

News reports of 1st egg:

2. Second egg hatched 45 hours later on Tuesday March 22 at 9:40pm. See video at top.

News reports of 2nd egg:

 

The last egg in the nest, Egg #3, is expected to hatch on Friday.

Watch the nestlings and chat about them at eagles.aswp.org.

Visit Audubon of Western PA’s eagle Facebook page for more information.

 

(YouTube videos captured by PixController from the Hays eaglecam. Watch Pittsburgh’s eaglecam sat eagles.aswp.org)

4 responses so far

Mar 21 2016

Questions About Eggs And Food

Hope at the nest, 20 March 2016 (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

Hope at the nest, 20 March 2016 (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

(You may have seen a bit of this on Facebook. Here’s more information.)

Since E2’s death many of you worry that Hope’s eggs at the Cathedral of Learning peregrine nest will not survive.

Some of you have even asked that we intervene to rescue and incubate the eggs ourselves, or that we leave food for Hope so she doesn’t have to leave the eggs.

Here’s why intervention is unnecessary, why “feeding” her will not work, and why either one of those attempts will wreck your viewing of Hope’s activities.

Why intervention is unnecessary:

Peregrine falcons delay incubation of their eggs until the female has laid the next-to-last or last egg. If the eggs are not incubated, but are protected from freezing and overheating (in other words, covered by the adult when temperatures are low or high), the eggs can wait several weeks for delayed incubation to begin and can hatch successfully.  I do not know the longest amount of time they can delay, but it is long.

We’ve seen this happen in Pittsburgh.  In 2010 Tasha laid two eggs at the Gulf Tower in mid March but Dori displaced her and became Louie’s new mate.  Tasha’s eggs waited three weeks while Dori bonded with Louie and laid her own clutch of three.  In the end, all five eggs hatched in May.

If Hope is delaying incubation, these eggs can wait a very long time.

And if she is not delaying:  Within the breeding season, peregrines lay a replacement clutch when they find a new mate or if the first clutch fails early in the season.

The bottom line is, you don’t need to worry about eggs.

 

Why leaving food for Hope will not work:

At the end of the last century when peregrines were endangered throughout the U.S. and Canada, they were so rare that wildlife officials tried to offer supplemental food to widowed females. It doesn’t work. Peregrines are not scavengers (bald eagles are) and we humans are the peregrines’ #1 enemy. It doesn’t matter where you leave the food.  Wild peregrines refuse food left by humans.

 

Why intervention of any kind will wreck your viewing of Hope’s activities:

Hope is at a first class “cliff,” a very valuable territory, so a new mate will find her.  If we intervened in any way, Hope and her new mate would decide the area is unsafe (from humans!) and would leave the Cathedral of Learning forever.  Then there would be no peregrines on camera at all.  Intervention would wreck everything.

 

Wild peregrines’ lives are often very different than we assume. It is a privilege to watch and learn from them.

 

(photo from Wikimedia Commons. Click on the image to see the original)

p.s. It is against Federal law to take birds’ eggs.  In Pennsylvania, peregrine falcons are managed and protected by the PA Game Commission. They make the decisions on peregrines and their welfare based on peregrine falcon biology.


 

For more information about peregrine falcon biology and family life see my Peregrine FAQs.

Stay up to date on peregrine news by checking this link.

50 responses so far

Mar 14 2016

Mallards Make Ducklings

Mallards (Anas platyrhynchos) are common ducks in the northern hemisphere so their courtship behavior is easy to observe.  Here are tips on what you’ll see in March as they prepare for nesting next month.

Did you know that mallards are already paired up by now?  They start forming pair bonds in September and most have a mate by the end of the year.  This leaves some unattached bachelors however because their sex ratio is usually skewed — 1.33 males for every female.

Now that they’re paired up they get down to the serious business of making baby mallards.  The video above shows several characteristic moves and sounds of a paired couple:

  • Head bobbing: a pre-copulatory action that gets them in tune with each other.
  • Inciting:  The female (all brown) incites the male by dipping her bill in the water over her shoulder.
  • Leading: He turns back his head, then swims away from her to lead her away from the crowd; she follows.
  • Vocalizations: He whistles. She quacks loudly (only the females make the loud quacking sound).

The excitement went out of the pair shown above, but the video below shows head bobbing and copulation. Notice that the male always grabs the female by the back of the neck as he mounts her.  After mating the pair bridles (rears up) and steams (swims with head low).  Sometimes the male turns back his head and leads again.

Mallards are monogamous but Cornell Lab’s Birds of North America says that “paired males actively pursue forced extra pair copulations” — a polite name for what looks like gang rape.  Knowing this, the paired males stay close to their females to protect them during the egg laying period.

After egg laying their match falls apart.  Male mallards desert their mates during incubation and won’t pair up again until autumn.  They can afford to do this because the females incubate alone and the ducklings are precocious.

So it’s only once a year that wild mallards make ducklings.

 

(videos from YouTube. Click on the YouTube links to see the originals)

One response so far

Mar 13 2016

First Egg at Pitt for 2016

Peregrine, nicknamed Hope, with her first egg of 2016 (snasphot from the National Aviary falconcam at Univ of Pittsburgh)

Peregrine, nicknamed Hope, with her first egg of 2016 (snasphot from the National Aviary falconcam at Univ of Pittsburgh)

Hope laid her first egg of the season at 9:32am today, 13 March 2016.

Congratulations, Hope and E2!

Watch the falconcam by clicking here or on the photo.

 

(screenshot from the National Aviary falconcam at Univ. of Pittsburgh’s Cathedral of Learning)

p.s. Here’s why she isn’t sitting on the eggs yet: http://www.birdsoutsidemywindow.org/peregrine-faqs/question-sitting-on-eggs-or-not/

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