At the Gulf Tower peregrine nest, Dori laid her first egg last night, Friday April 2, at 10:45pm.  She laid it in the same scrape where Tasha, the former resident female, had laid her two eggs before she lost the site to Dori.

According to Birds of North America Online, for peregrines “completed copulations begin at least 2 wk prior to egg-laying.”  Dori won the site on March 20 so my mental calculation had her first egg arriving two weeks later.  This first egg is right on time — even a little early.   

In the top photo, Dori is guarding the eggs.  In the bottom photo, a close-up:  two of the eggs are Tasha’s, one is Dori’s new one.  Thanks to all who sent me snapshots.

And thanks to Jennie and Michelle for posting comments when they saw Dori lay her egg last night.  Click here for a nighttime screenshot from Michelline, taken just after Dori laid her first egg.

(photo from the National Aviary webcam at the Gulf Tower)

Yesterday at lunchtime Karen Lang and I saw a brief peregrine encounter at the University of Pittsburgh.

It started when I saw a peregrine circling very high above the Cathedral of Learning almost invisible against the bright blue sky.  Based on size I guessed it was a male.  I assumed it was E2 — except it didn’t act like him.

The bird dove obliquely toward Heinz Chapel without losing much altitude.  Dorothy came off the Cathedral and made a large, sweeping circle but didn’t fly with the other falcon.  This was odd.

Was this bird E2?  Or was he on the eggs?  A quick check of the snapshot camera using my cell phone showed E2 still incubating. 

This peregrine was a third bird.

Peregrine falcons don’t always fight when they encounter each other.  They can signal their status by the way they fly. 

The third bird stayed very high and made another small circle above campus.  At this point E2 came off the eggs — he wasn’t in a rush, he paused to stretch first — and circled with Dorothy.  The third bird could see this territory was claimed.

E2 returned to the eggs and Dorothy to the top of the Cathedral of Learning.  The third bird circled once more, then set its wings and sailed toward Downtown Pittsburgh.  There was no sound during this encounter.  Later, Dorothy creaked a few times from her distant perch (heard on the video archives).  All was calm.

Who was this third peregrine?  Was it someone they knew?  A youngster from a prior year?  Or was it a visitor, checking the scene.

We’ll never know.

(photo by Kim Steininger)

That’s the question all the peregrine watchers are asking.

It’s been ten days since Dori won the Gulf Tower site from the previous female resident, Tasha, and eleven days since Tasha laid her last egg.

For a while neither Louie nor Dori did anything with the old eggs except court and bow over them.  Sometimes Dori pushed them out of the scrape.  Later Louie would push them back in.

Then over the weekend Louie started incubating Tasha’s eggs for an hour or two at a time.  As is typical for male peregrines, he didn’t incubate them overnight but he showed up when expected — at dawn and early afternoon — as if he was taking his normal incubation duty shift.  Dori didn’t participate.

This puzzled everyone.  Are Louie and Dori disagreeing about the eggs?  Will Dori refuse to lay her own if the old ones are present?  Are the old eggs viable?  Will Louie eventually give up on them?  Will Dori eventually adopt them?

As much as this seems a drama to us, something very simple is going on.  Louie and Dori are at different stages in the nesting sequence.  He has eggs, she doesn’t.  When she lays eggs she’ll catch up to him.

Keep in mind this couple has known each other for only ten days.  If their courtship goes well — and that appears to be the case — Dori’s hormones will trigger egg laying.  She can’t “refuse” to lay eggs.  She won’t have any choice about it, and she’ll have to put them somewhere.  The only thing she could possibly refuse is the ledge where her rival nested, but she hasn’t done that.  She courts at the nestbox, she rearranges the gravel and she digs at the scrape where the old eggs were laid.  Dori will lay eggs when she’s ready.

Humans are impatient during a slow drama like this one.  Watching the webcams is a lot like watching television so we expect the action to unfold a lot faster.  But remember, the nature programs leave out all the boring bits.  They have only an hour to show you a whole year of a bird’s life.

Give this pair some time.  Nature is taking its course.

p.s. The old eggs might not be viable.  If so, the adults will move them away if they don’t hatch.

(photo of Louie from the National Aviary webcam at Gulf Tower.  Thanks to Traci Darin for the screen capture.)

Something strange has been going on at Gulf Tower since last weekend.  Now we know why!

It began Friday night, March 19.  Tasha sat on the nest at 10:40pm and watched the sky.  Within minutes she stepped out of view and from that point onward we heard periodic wailing for most of the night, though no peregrine was visible.  Wailing can mean many things including “come here” and “stay away,” but it isn’t the sound of peregrines locked in combat. 

That night there was no evidence of a fight at the nest — no fight sounds, no birds on camera. 

An hour before dawn Tasha returned to the nest and slept.  Half an hour later Louie arrived and tried to bow with her but Tasha would not bow.  She looked at him, then left to tackle whatever was out there.  It was a young female peregrine challenging her for the site.

For three and a half hours nothing happened.  Silence.  Then Tasha arrived at the nest, all pumped up and running on adrenaline (if peregrines have adrenaline).  She was sleeked for battle and her left wing drooped, an old injury she hid most of the time.  She shouted excitedly to Louie and left quickly.  

Louie lingered at the nest for several minutes.  At one point he stood over Tasha’s two eggs, yipping softly, but something in the sky soon distracted him and he bounded off stage.  In half an hour Tasha appeared again very briefly.  That was 10:45am, the last time she appeared on camera.

Seven hours of silence.  Nothing except for two brief visits by Louie alone. 

Then at 5:45pm Louie arrived at the nest and called, “Come bow with me.”  His audience needed encouragement.  He called and called, bowed and bowed.  Finally his new lady arrived, a female peregrine with a pale back, no white wing feather and in top physical condition.  For the next several hours they repeatedly courted at the nest.  She was now his queen.

That was Saturday night, March 20.  There are no video archives for several days after that, but everyone watching the falconcam knew the situation was odd.  Why were two peregrines at the nest but no one incubating the eggs?  

Yesterday Dr. Todd Katzner of the National Aviary went to the Gulf Tower to solve the mystery.  He was able to observe the new female and read her bands as she courted with Louie: black/green M/93.  Born at the Landmark Building in Akron, Ohio in 2007, her back is paler than Tasha’s and her wings are normal.  She has no white wing feather. 

Since Monday the fervent peregrine watchers at Make-A-Wish, whose offices are near the nest, suspected Tasha was gone forever.  They’ve been Tasha’s fans for many years and were sad about this turn of events, so they wanted to honor the new female with a happy, hopeful name.  Even before they knew her identity they called her Dori, which means “wish” in Romanian. (*)

Dori has wanted to nest in Pittsburgh for quite a while.  She first tried the 62nd Street Bridge where she was identified last October by Dan Yagusic, but she kept a lonely vigil there, unable to attract a mate to the site.  In January Dan found her at the 40th Street Bridge, still alone.

As spring approached her hormones kicked in as they do for all peregrines.  Dori needed a nest and a mate.  The bridges were fruitless.  She flew downstream… and the rest is history.

Tasha was a very successful peregrine.  When she disappeared last weekend she was at least 14 years old and had raised 44 young at the Gulf Tower.   

We wish the same great success for Dori.  May she live long and have many babies!  

And, yes, we’re all watching for her first egg.

(two snapshots of Dori from the National Aviary webcam at the Gulf Tower)

p.s. Remember the video of two peregrines courting on Saturday evening?  I was wrong!  Tasha isn’t in that picture.  They’re Louie and Dori.  Click here to watch.

(*) Dori has many names.  Dori is her nest site name, Mary Cleo is her banding day name, and Louie has a special name for her that is unpronounceable by humans.