Archive for the 'Nesting & Courtship' Category

Jan 27 2016

Eagle Season Starts With A Bang!

Harmar Bald Eagle carrying nesting material, March 2013 (photo by Steve Gosser)

Harmar bald eagle carrying nesting material in March 2013 (photo by Steve Gosser)

For one of Pittsburgh’s three bald eagle pairs, this year started off with a bang.

Since late 2013 the Harmar pair that nests along the Allegheny River have been hard to observe because PennDOT blocked off the nearest viewing area while building a replacement for the 107-year-old Hulton Bridge.  Steve Gosser took the photo above from that viewing location in March 2013. It’s been hard to get good photos for years.

Last October the new bridge was completed and dedicated but the eagle viewing area was still closed while PennDOT began to deconstruct the old bridge.  However …

Yesterday morning, in a flash of light and sound, the old Hulton Bridge was imploded into the river.  Here’s a video from Dave DiCello, posted at The Hulton Bridge Blog on Facebook. (Dave also filmed the Greenfield Bridge implosion last month.)


Staff from the Audubon Society of Western Pennsylvania were on hand to monitor the eagles just in case.  As ASWP reports below, the eagles weren’t affected at all. They were 3.4 miles away as the crow flies.  (The eagles would have flown along the river, which is even longer.)

The Harmar eagles were down river near the Fox Chapel Yacht Club at the time. Our staff member monitoring the eagles said that the birds “didn’t even flinch” at the sound of the implosion.

The eagle viewing zone at Harmar will be closed a while longer but you can watch this pair easily now on the Audubon Society of Western Pennsylvania website.  ASWP has both the Hays and Harmar eagles’ nests streaming live at Click here to watch.

And for more images of the Hulton Bridge coming down, check out The Hulton Bridge Blog on Facebook and this story with videos at KDKA.


(photo of Harmar female eagle, March 2013, by Steve Gosser. Video by Dave DiCello)

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Dec 11 2015

New Digs!

Gulf Tower peregrine nest with new digs! 10 Dec 2015 (photo by Kate St. John)

Gulf Tower peregrine nest with new gravel and ramp, 10 Dec 2015 (photo by Kate St. John)

The Downtown peregrines have new digs at the Gulf Tower.

Last month the weeds in the Gulf Tower nest indicated to Art McMorris (PA Game Commission Peregrine Coordinator) that the nest needed a makeover.  Fortunately the wooden box and hood were fine so …

Yesterday Art came to town with 10 bags of pea gravel, a new wooden ramp and lots of tools to refurbish the nest. At 80 pounds per bag that’s a lot of lugging.
10 bags of pea gravel for the nest (photo by Kate St.John)

Here, he makes note of the site conditions before he begins.  The edge behind him is a sheer 37-floor drop to the street.  No way! I stayed inside.

Art McMorris records the stats before beginning, 10 Dec 2015 (photo by Kate St. John)

First order of business: Shovel out the old gravel into many(!) garbage bags.  Art shoveled while Bob Mulvihill and Eric Fialkovich of the National Aviary hauled the bags over the transom and into the hall for later disposal.

Digging out the old gravel. No drainage! (photo by Kate St. John)

As soon as the old gravel was gone the problem was obvious. There were no drainage holes in the base so all the water stayed in the box. Peregrines don’t like wet gravel and neither do we. Art drilled 77 7/16″ holes.

Drilling holes so the gravel will drain (photo by Kate St. John)

Then he dumped in and smoothed the new gravel.

gulfnest_05_addinDumping in the new gravel, bag by bag (photo by Kate St. John)

He needed only six bags.

Art spreads the gravel (photo by Kate St. John)

Art added the new ramp and Ta Dah!  It’s as good as new (shown at top).

The new gravel is such a different color that I’m hoping the peregrines get curious and come to check it out.  When they do they’ll find clean, dry gravel to dig their toes into.

Fingers crossed that they like it well enough to nest here next spring.


(photos by Kate St. John)

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Nov 23 2015

Weedless And Waiting

Weed-free at the Gulf Tower nest, 20 Nov 2015

Weed-free at the Gulf Tower nest, 20 Nov 2015

Remember how I said the Gulf Tower peregrine nest needs a makeover?  Well, the makeover has begun but this new look is only an interim step.

Because peregrines are still endangered in Pennsylvania, they and their nests are directly managed by the Pennsylvania Game Commission, often aided by local volunteer monitors (me + others) and local organizations that sponsor the nests (in urban Pittsburgh, the National Aviary).

The original plan was that Art McMorris (PGC) would arrive on Friday, November 20 with new gravel and supplies. Bob Mulvihill was going to help him dig out the old and put in the new, and I planned to provide indoor support.

Fortunately Art asked an important question early last week:  What is the condition of the nest box structure?

Uh Oh!  The structure is 24 years old!  The wood that holds the gravel will probably fall apart when the gravel is removed.

So Art changed the plan.  As soon as he can he’ll install a new nest box that will resemble this highly recommended model, favored by peregrines for many years.

Standard peregrine nest box (photo courtesy Art McMorris, PGC)

Standard peregrine nest box (photo courtesy Art McMorris, PA Game Commission)

In the meantime, Friday didn’t go to waste. The National Aviary’s Bob Mulvihill and Eric Fialkovich removed the weeds and used a garden claw to loosen the gravel so the peregrines don’t lose interest in the site.  (Peregrines like gravel or dust, not weeds and sticks!)

Here are before and after photos from Bob Mulvihill’s cell phone.  That’s Eric on the right.

Gulf Tower nest -- before and after weeding (photos by Bob Mulvihill)

Gulf Tower nest, before and after weeding (photos by Bob Mulvihill)


So now the old box is weedless and waiting.

Stay tuned for the next step.


(photo of the nest from the National Aviary’s falconcam at Gulf Tower. Photo of new nest box model courtesy of Art McMorris, PGC. Before and after photos of the Gulf nest weeding by Bob Mulvihill.)

p.s. I provide “indoor support” because I am too afraid of heights to go out on the ledge. (!)

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Aug 06 2015

Save Time: Reuse, Recycle

Cordilleran flycatcher at the nest, Mount Lemmon, AZ (photo by Donna Memon)

Cordilleran flycatcher at the nest, Mount Lemmon, AZ, 3 August 2015 (photo by Donna Memon)

Last week, Karyn Delaney reported a northern cardinal using an old robin’s nest outside her window and we joked in email that the mother took this shortcut because it’s so late in the breeding season.

Cardinals rarely reuse nests but some songbirds do.  On Monday Donna Memon and I found a Cordillean flycatcher at her(*) nest at the summit of Mount Lemmon.  Because her nestlings were too tiny to see and the nest edges and “launch pad” had fecal evidence of active fledglings, we surmised she was reusing the nest.

Birds of North America Online (BNA) reports that Cordillerans in the Santa Catalina Mountains in Arizona — the location of Mount Lemmon — build a “cup of moss, sometimes mixed with bark strips or rootlets, [and] lined with fine grass or rootlets.” Cordillerans often reuse nests, sometimes in the same location for 20 years.  Perhaps this nest has been recycled many times because it’s much sloppier than a simple cup.

In the next three photos the flycatcher feeds and watches her tiny nestlings but she has to hurry because …

Cordilleran flycatcher feeding young, Mount Lemmon, AZ (photo by Donna Memon)

Cordilleran flycatcher feeding young, Mount Lemmon, AZ, 3 August 2015 (photo by Donna Memon)

Cordilleran flycatcher at nest, Mount Lemmon, AZ (photo by Donna Memon)

Cordilleran flycatcher at nest, Mount Lemmon, AZ (photo by Donna Memon)

… this is a late nesting.  Winter comes early to Mount Lemmon and Cordilleran migration begins in mid-August so she’ll have to hurry.

It looks like she’s already saved time by reusing the nest.


(*) A NOTE ABOUT “Cordilleran and “she”:  Empidonax flycatchers are notoriously hard to identify but the Cordilleran flycatcher is the Empid species that nests on the summit of Mount Lemmon, a sky island in southeastern Arizona.  The Cordilleran’s look-alike relative, the Pacific slope flycatcher, is a low elevation bird. Also, for convenience I’ve called this bird a “she” but the males help feed the nestlings so we may have been watching a “he.”  On the subject of “he/she” I am borrowing my husband’s Poetic License.  😉


(photos by Donna Memon)

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Jul 14 2015

Find The Whimbrel

Whimbrel with eggs (photo by Dr. Matthew Perry, USGS)

Whimbrel with eggs at Churchill, Manitoba, Canada (photo by Dr. Matthew Perry, USGS)

Can you see the whimbrel and four eggs?

These ground-nesting shorebirds have natural camouflage but I’ll bet you can see the one above because the eggs have shadows and the bird’s mouth is open.  If you were holding the camera you’d hear the whimbrel shouting like this.

Whimbrels (Numenius phaeopus) nest in the northern tundra around the world.  In North America they lay eggs in the first week of June that hatch in the first week of July.  Mom stays with the family 3-14 days after the chicks hatch.  Then she leaves on migration while dad stays with the kids until they fledge in August.  The kids don’t leave until September.  This means that some sort of whimbrel is on the move in North America from July through September.

Successful mothers and birds whose nests have failed arrive on northern coasts in July on the first stage of their long migration.  Mary Birdsong saw this one yesterday at Presque Isle on Lake Erie’s shore (video below).

Their early stops are only way stations where the whimbrels fatten up for their transoceanic trips.  Some North American whimbrels fly non-stop 2,500 miles to South America.  (Others save time by wintering on the southern U.S. coast.)

Asian whimbrels spend the winter as far south as Australia. Here’s a group in Singapore.

Whimbrels wintering in Singapore (photo by Lip Kee via Wikimedia Commons)

Whimbrels wintering in Singapore (photo by Lip Kee via Wikimedia Commons)

But on migration they travel alone.

This month, if you’re lucky, you might see a whimbrel on the shore.  You’ll see it when its long down-curved bill stands out. Woo hoo!


(photo of whimbrel at nest by Dr. Matthew Perry, USGS. Video of whimbrel at Presque Isle State Park 13 July 2015 by Mary Birdsong. Photo of whimbrels in Singapore by Lip Kee via Wikimedia Commons.)


p.s. I often go to Conneaut Harbor, Ohio to find shorebirds but the sandspit is inundated right now because the harbor water level is 20 inches higher than normal.  See this message at OhioBirds.

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Jul 13 2015

Father-Daughter Pair in Norfolk

'Dad' and 'tHE Missus', Norfolk, Virginia (photos by Mike Inman, used by permission)

‘Dad’ and his mate ‘HE’ in Norfolk, Virginia, 2015 (photos by Mike Inman used by permission)

In a recent Peregrine FAQ I described how peregrine falcons are not social creatures like we are.  In fact most raptors don’t hang out with their relatives, so that siblings from different years and birds separated by more than one generation can’t know that they’re related.

Since they don’t know their relatives, how do raptors avoid interbreeding?  By traveling.

Young raptors naturally disperse far from home and females typically travel twice as far as males, thereby mixing the gene pool.  Here’s how far some of Pittsburgh’s peregrines traveled from where they were born:

  • Downtown Pittsburgh: Louie dispersed 2.3 miles, Dori traveled 93 miles from Akron, Ohio
  • Cathedral of Learning: E2 dispersed 2.3 miles, Dorothy traveled 450 miles from Milwaukee, Wisconsin
  • Neville Island I-79: Beau dispersed 10.7 miles, Magnum traveled 79 miles from Canton, Ohio

Bald eagles are much more social than peregrines. They fish and roost together in early winter but when it comes time to breed they disperse far and wide.  Close interbreeding among bald eagles is rare.

That’s why it was such a surprise to discover that this year’s pair nesting near Norfolk Botanical Garden is father and daughter.

The male is not banded but he has a unique tiny black dot in his left iris, called an inclusion, that’s visible in good photographs. This identified him as the 25-year-old male that used to nest in the Garden.

His mate is banded with the code “HE,” a band she received six years ago when she was a nestling at Norfolk Botanical Garden.  Yes, she’s his daughter.

Their close relationship was reported this spring by the Center for Conservation Biology (CCB) that monitors bald eagles in Virginia and banded “HE” in 2009.   CCB’s blog article provides details and photos.

It’s unusual for a female to settle so close to her birthplace but this location has had many challenges.  After the old female was killed by an airplane at nearby Norfolk International Airport in 2011, eagles were no longer allowed to nest at the Garden.  The male and all his potential mates were harassed away.  Nine nests were destroyed.  All the females left. The male didn’t nest for three years.  (Click here for the story.)

Unusual as this pairing is, the good news is that he finally found a mate, they found a safe place to nest, and together they fledged one eaglet on May 29.

It all worked out in the end.


(photos of the NBG pair courtesy of Mike Inman,

p.s. As part of their monitoring efforts CCB recently identified a female bald eagle with an unusual story. Click here to read about ‘Dolly’, born at the Birmingham (Alabama) Zoo to injured, unreleasable parents, she now nests along the James River in Virginia.

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Jul 04 2015

277 and Counting

Hays bald eagle carrying nesting material, March 2015 (photo by Dana Nesiti)

Hays bald eagle carrying nesting material, March 2015 (photo by Dana Nesiti)

277.  That’s how many bald eagle nests there are in Pennsylvania this year. What an improvement since the time when there were only 3 nests back in 1983!

As the PA Game Commission explains:

“So far this year, 277 bald-eagle nests have been documented in Pennsylvania, with nesting eagles present in at least 58 of the state’s 67 counties.  That shatters the 2014 preliminary number of 254 nests, which also was an all-time high. And more nests remain to be counted as the year goes on.”

The count will go up, not because bald eagles are building new nests in July, but because observers will report additional nests in the days ahead.

Many people don’t realize that the nest count starts over every year. Nests that are used year after year must be reported again to be included in the count.

Patti Barber, a biologist with the Game Commission’s Endangered and Nongame Birds section, says, “Even if nests are well known locally, please don’t hesitate to report them. You might be adding a new nest to the list, or making certain that one reported in a previous year is accurately counted this year.”

It’s easy to report a nest. Just email the Game Commission at with “Eagle Nest Information” in the subject line, or phone it in to your Game Commission Region Office or the Harrisburg headquarters.

Perhaps your report will help bald eagles break the 300 mark.


(photo of a bald eagle at Hays by Dana Nesiti)

p.s. Peregrine falcons are rare compared to bald eagles. There are only 45 peregrine nests statewide this year.

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Jun 16 2015

Nest Watching In The Sagebrush Sea

Watching raptor nests on the Internet may give you the impression that any nest can be monitored this way, but many species are too skittish or too remote for a webcam.

When Cornell Lab of Ornithology filmed The Sagebrush Sea they included footage of ferruginous hawks nesting in a remote sagebrush prairie.  No electricity.  No Internet.  No road.  How did they get that footage?

The video above shows Gerrit Vyn’s long hours of hiding alone in a very small space.  Thanks to his efforts we get a special view of ferruginous hawk family life that’s rarely seen on camera.

If you missed last month’s broadcast of The Sagebrush Sea, watch the complete program online here at PBS.

Nest watching can be a lot harder than sitting at a desk!


p.s.  The activity at this nest has a lot in common with other raptor nests.  I love the interactions among the chicks!

(video from Cornell Lab of Ornithology)

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Jun 10 2015

Below The Nest

The chick almost matches the nest, 8 June 2015 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Peregrine chick gazes toward the sky, 8 June 2015 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Some of you watching the Cathedral of Learning falconcam have worried that the chick is missing (sometimes) or that he will fall off the nest.  Here’s why neither of those things have happened and what you can expect in the future.

Peregrine falcon nestlings will not step off the edge until they are fully feathered and ready to learn to fly.  This inherited safeguard is hard-wired because all of today’s peregrines are descended from birds who would not step off the edge.

At 28 days peregrine nestlings move around the nest area but they’re speckled and hard to find.  If you don’t see them, they didn’t fall.  They’re hidden in plain sight.

At 35+ days they’re fully feathered and ready for wing practice.   At this point they have to move to nearby ledges (off camera) or they’ll never learn to fly.

Stepping out can be dangerous at bridge sites.  Bridges have water below, no lower ledges, the wind blows hard, and if a fledgling lands on the ground it may be killed by predators or vehicles.  Bridges have higher fledgling mortality rates than good cliffs.

None of these hazards apply to the Cathedral of Learning.  There is no water, there are many ledges for landing below the nest, and it’s impossible for a young bird to fall directly from the nest to the street.

The nest box stands on a floor surrounded by walls. A chick that jumps or bumps to the floor cannot get to the street. The front wall is so tall that Dorothy and E2 use it to perch above the nest (above the camera).  You see them arrive and depart from that direction.  Here’s an overhead diagram of the site.

The Cathedral of Learning nest is surrounded by high and low walls (diagram by Kate St. John)

The Cathedral of Learning nest is surrounded by high and low walls (diagram by Kate St. John)

The box itself is elevated with room to explore underneath it.  If a chick reaches the floor, Dorothy teaches him to come back to the surface by waiting for him to climb up on his own.  This is an important learning experience for the chick.  The explorer always resurfaces.

Nestbox looks like this if it stood alone (diagram by Kate St. John)

Nest box is elevated (diagram by Kate St. John)

Our most famous under-nest explorer was Green Boy in 2010.  One of five in an active crowded nest, his brother bumped him off the front perch.  Green Boy spent many hours exploring the gully and then came topside in this hotspot video footage.  (Read all about his adventure and see additional footage here.)

So, no worries about the gully.

The only First Flight hazard for a young peregrine at the Cathedral of Learning is this:  Curious People.

Curious people think “It won’t hurt if I sneak up close to take a look/picture.”  But it will.

Before a peregrine learns to fly it walks off the nest to nearby ledges and practices flapping its wings (off camera).  Adult peregrines teach their kids that humans are dangerous.  If a youngster sees a human near him while he’s ledge walking, he may try to fly away before he is able and crash below.

So, curb your curiosity.  Stay away from peregrine nests while youngsters are learning.

You don’t want to be the one who scared the chick and ended his life in a crash!


(photos from the National Aviary falconcam at University of Pittsburgh. Diagrams by Kate St. John)

p.s.  You cannot see the nest from inside the building nor can you see it from the street. To see the Pitt peregrines, come down to Schenley Plaza.

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Jun 02 2015

Pitt Peregrine Discovered at Neville Island

Male peregrine at Neville Island I-79 Bridge (photo by Peter Bell)

Male peregrine at Neville Island I-79 Bridge was born at Pitt (photo by Peter Bell)

Though all eyes were on the peregrine chick at the Cathedral of Learning last Friday, it was also Banding Day at a second Pittsburgh area nest.

After wrapping up in Oakland, I went with PGC’s Art McMorris and Dan Puhala to the Neville Island I-79 Bridge.

Neville Island I-79 Bridge (photo by Kate St. John)

Neville Island I-79 Bridge (photo by Kate St. John)

While Art and Dan climbed in the bridge structure with their PennDOT guide, I kept my feet firmly on the ground with nest monitors Anne Marie Bosnyak and Laura Marshall, and with three peregrine enthusiasts: Pitt follower Peter Bell, and Canton, Ohio peregrine monitors Chad Steele and Ray Glover.  Chad and Ray drove two hours to see this banding because the mother bird, Magnum, hatched in downtown Canton in 2010.

Magnum kaks a warning, 29 May 2015 (photo by Peter Bell)

Magnum defends her nest, 29 May 2015 (photo by Peter Bell)

Magnum kicked up a fuss(!) kakking, swooping, even running, always shouting at the top of her lungs.

Her nest is hidden in a box-like recess so the only way Art could retrieve the chicks was to perch over open water and reach in barehanded to feel for them one at a time.  Magnum positioned herself inside the nest between Art’s hand and the chicks and slashed at him with her talons every time he reached.  Ow!

Art McMorris of the PA Game Commission hands off a peregrine chick at the Neville Island I-79 bridge, 29 May 2015 (photo by Peter Bell)

Art McMorris of the PA Game Commission hands off a peregrine chick at the Neville Island I-79 bridge, 29 May 2015 (photo by Peter Bell)

While this was going on Magnum’s unidentified mate gave vocal support from a distance.  For years we’ve known he’s banded but couldn’t read his bands. In the excitement he perched above us and Peter got a clear photograph: Black/Green 05/S.

Male peregrine at Neville Island I-79 Bridge (photo by Peter Bell)

Male peregrine at Neville Island I-79 Bridge (photo by Peter Bell)

I whipped out my Pittsburgh peregrine genealogy (who else would carry this!) and scanned the band numbers.  Surprised to find a match, I learned this bird hadn’t traveled far.  He hatched at the Cathedral of Learning in 2010, son of Dorothy and E2 and the older brother of this year’s chick.  Unnamed at banding, (temporary name was White) Anne Marie and Laura can now give him a permanent name.

His four nestlings at Neville Island I-79 Bridge — three male, one female — are E2’s grandkids.  They’re due to fledge around June 11.

The Pitt Peregrine dynasty continues!


(bridge photo by Kate St. John.  All other photos by Peter Bell)

PGC = Pennsylvania Game Commission

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