Monthly Archives: April 2013

Peregrines at the Water Tower!

Peregrine at the Greentree Water Tower (photo by Shannon Thompson)

There’s a new pair of peregrines in town and they’ve already made the news.

“Nesting Falcons halt Green Tree water tank work,” read the headline in the Post-Gazette yesterday.  “Pennsylvania American Water has delayed a project to sandblast and repair the interior of its 2.5-million-gallon water storage tank in Green Tree after spotting a nest of peregrine falcons.”

The nest would have failed but for a handful of dedicated observers.

Back in March a former Aviary volunteer spotted peregrines at the Green Tree water tower.  Her report made its way to me but without a contact name her information languished.

In mid-April Chuck Dinsmore heard kakking and saw a peregrine flying around the water tower during his morning commute.  His wife Vicki went there with binoculars and found a lot of workmen banging away and a peregrine perched on a ledge under the bulb of the water tower (pictured below).  No wonder the peregrine was upset.

Water tower ledge (photo by Vicki Dinsmore)

The banging phase was short-lived but in subsequent visits Vicki and Chuck learned of plans to sandblast and paint the tower.  Vicki called WQED to let me know.

Her concern was infectious.  I notified the PA Game Commission (PGC) of a possible nest near imminent construction and called for more observers on PABIRDS.  Could someone check the water tower?

Shannon Thompson took up the challenge and photographed a peregrine perched beneath the Green Tree “G” on April 21.  The vertical striping on his breast indicates he’s a one-year-old bird so when I sent her photos to Art McMorris (PGC’s Peregrine Coordinator) I said, “Oh well, a juvenile bird,” but Art cautioned that one-year-old’s can breed so we couldn’t rule out a nest.

A few hours later Mary Jo Peden — the former Aviary volunteer! — contacted WQED to tell me that she’d seen a pair of peregrines courting at the water tower and mating as recently as the week of April 8.  She described their ledge and said she was worried about the coming construction project.  I quickly sent this news to Art with contact information for Pennsylvania American Water.

Everything was quiet for a week.  Could the Game Commission get through to the water company in time?  Then yesterday the Post-Gazette set my fears to rest.  Hooray!

Welcome to the neighborhood, new birds, and a big thank you to everyone involved!

If you’d like to see where they live their observers (and rescuers) suggest visiting the park behind the Green Tree Borough City Office.  Look beneath the G.

Vantage point for watching the Greentree peregrine (photo by Shannon Thompson)


(peregrine and tower photos by Shannon Thompson.  Ledge photo by Vicki Dinsmore)

p.s.  Based on Mary Jo’s observations you’ll probably see only one bird until mid-May when the eggs hatch.  My hunch is that this juvenile is the male, standing guard.

Things Are Getting Back to Normal

E2 removes the dead chick from the nest (photo from the National Aviary falconcam at Univ of Pittsburgh)

In this morning’s blog I mentioned that Dorothy was still brooding the dead chick but that E2 would eventually take it away for disposal.

Today at 4:00pm he did just that.   E2 distracted Dorothy by bringing supper for Baby so she left the nest to prepare the meal.

In three minutes Dorothy returned with the very large meal.

Baby seems to be saying, “Is all that for ME?”

Dorothy brings baby's supper (photo from the National Aviary falconcam at Univ of Pittsburgh)


So cute!

Dorothy feeds baby, 29 Apr 2013 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Things are getting back to normal.

(photo from the National Aviary falconcam at the University of Pittsburgh)

What happened?

Dorothy, 1 chick, 3 eggs, 28 April 2013 (photo from the National Aviary falconcam at Univ of Pittsburgh)

Since the news yesterday that one of the Pitt peregrine chicks died and that the three remaining eggs won’t hatch, many of you have asked questions in email, Facebook and blog comments.   Here are some answers, collected in one place.

After consistently raising three to five chicks every season, this year Dorothy has one healthy chick, one handicapped and now dead chick, and three unhatched eggs.  It isn’t the cold weather or poor parental care.  It’s because Dorothy’s getting old.   She’s 14.

Older female peregrines become less fertile.  History at other nest sites bears this out.  In the last two years of Tasha’s reign at the Gulf Tower she hatched 2 of 4 eggs and 2 of 5 eggs.  In 2010, in what was probably her 14th year, Tasha laid two eggs and then was displaced by Dori.   At the Terminal Tower in Cleveland, Tasha’s daughter SW is now 14 and has hatched only 2 of 4 eggs.  A similar pattern occurred at the Harrisburg site when their female aged a few years ago.

What will happen to Dorothy?   Dorothy is my very favorite peregrine in all the world.  I don’t like to think of it, but she is mortal just like the rest of us.  Frankly, it’s a good thing I can’t predict what will happen.  Time itself will tell.  Meanwhile I’m pleased as punch that she’s a mother again and has grandchildren, great-grandchildren and — if I only knew where — great-great grandchildren.  Go, Dorothy!

Brooding the dead chick:  After the handicapped chick died Dorothy drew it back into the nest and is brooding it along with the live chick and her 3 unhatched eggs.  I believe she knows the little one is dead but she’s doing what comes naturally — keeping everything warm until she’s absolutely sure.  I suspect E2 will remove it at some point when Dorothy is away as he did when one of the five chicks died in 2011.

What will happen to the unhatched eggs?  Dorothy will brood them along with Baby until he’s able to thermoregulate and moves off the nest.  Brooding lasts 8-12 days but can be shorter in warm weather.  When Baby is mobile, the parents will push aside the unhatched eggs where they will either desiccate or rot.  Last year’s unhatched egg rotted and smelled awful when it broke on WCO Beth Fife’s shirt during the banding.

Does the empty shell mean another egg has hatched?  No, this is an old shell that is swept from here to there by Dorothy’s tail.

Will the only chick do well?   If he’s healthy, yes.   Baby will get 100% attention from two very experienced parents.  Dorothy was an “only child” and is proof that only children can go far.


(photo from the National Aviary falconcam at University of Pittsburgh)

Just One Now

Dorothy feeds one chick, 27 April 2013 (photo from the National Aviary falconcam at Univ of Pittsburgh)

When you watch a feeding at the Cathedral of Learning peregrine nest you’ll see just one baby now.

As early as Friday morning, only 12 hours after he hatched, I could tell something was wrong with Chick#2.  He was noticeably weaker and his movements were odd and uncoordinated.  He seemed to have a developmental problem that caused spasms.

The big clue was that he left the nest.  This is abnormal and life-threatening behavior in a chick so young.  Peregrine nestlings must be brooded by their parents during their first week of life because they can’t thermoregulate yet.

On Friday afternoon Chick#2 literally rolled in a ball out from under Dorothy’s tail.
Chick#2 rolls in a ball out from under Dorothy (photo from the National Aviary falconcam at Univ of Pittsburgh)


And here he moved outside Dorothy’s wing in 41 degree weather on Saturday morning.  He must be twitching a lot considering the look on her face.
Chick#2 twitchy outside Dorothy's wing (photo from the National Aviary falconcam at Univ of Pittsburgh)


Midday Saturday he moved out of the nest scrape and did not return for feedings.  Here Dorothy and E2 seem to confer about him on Saturday afternoon.  (He is lying in the shade beyond them.)  There was nothing to be done. He was too handicapped to survive.
Dorothy and E2 confer about Chick#2 (photo from the National Aviary falconcam at Univ of Pittsburgh)

This leaves just one surviving baby out of five eggs.  Until this year Dorothy always raised three to five young per nesting season — but she is 14 years old now.

Her low hatch rate and handicapped chick are both normal outcomes considering her age.  Just as in humans, older mothers have fewer babies and are more likely to produce handicapped young.

I am sorry to see this happen because Dorothy is my very favorite peregrine.  But the reality is that Dorothy, like all of us, is aging.

The good news is that Chick#1 is healthy and vigorous.  He will get lots of attention and education from his very experienced parents.

One bright-eyed chick awaits breakfast, 28 Apr 2013 (photo from the National Aviary falconcam at Univ of Pittsburgh)

(photos from the National Aviary falconcam at the University of Pittsburgh)


Red trillium or Wake-robin (photo by Dianne Machesney)

Here’s a flower with a bird’s name.

Blooming now in western Pennsylvania, the red trillium (Trillium erectum) is sometimes called wake-robin, perhaps a reference to the robin’s red breast though their colors aren’t the same.

The flowers smell like rotting meat because they’re pollinated by flies. This gives the plant another name: Stinking Benjamin.  Have you ever noticed that fly-pollinated flowers are often this color?

Look for wake-robin in woodlands this weekend.   Dianne Machesney found these near Monroe Road on the Butler-Freeport Trail.

(photo by Dianne Machesney)

Eggs’ Potential

Anatomy of an egg (illustration from Wikimedia Commons)

We’ve had eggs on our minds this week while we’re watching them hatch at the Cathedral of Learning peregrine nest.

Eggs start as the familiar objects we see every day in our refrigerators and miraculously become baby birds.  The process is so amazing that I’m devoting two Tenth Page articles to it.

Shown above is the un-incubated egg we know so well.  If fertilized before it’s laid — and then incubated — it becomes a bird.  Each component plays a part.

  • Blastodisc or germinal disc:  Potential embryo.  If fertilized and incubated this small circular spot on the yolk becomes a chick.
  • Yolk:  Food for the embryo.  The female’s ovary deposits layers on the yolk to increase its size before ovulation.  Yellow layers are laid on during the day, white ones at night, so the yolk has rings like a tree.  It’s housed in a yolk sac which is why you have to “break” the yolk when cooking.  The yolk is ovulated with the germinal disc attached (cradled by the yolk) so the food is next to the potential embryo even before fertilization.   As the embryo develops, the yolk shrinks.
  • Albumen = Egg White:  Food, water, shock absorber, and insulation from sudden temperature changes.  The albumen makes up 50% to 71% of the egg’s total weight.  It’s laid on after fertilization while the yolk-with-germinal-disc rotates gently in the oviduct.  As the embryo develops the albumen shrinks too.
  • Chalazae:  Because the yolk is rotating during albumen deposition, twists form in the albumen.  Chalazae act like springs and stabilizers to keep the yolk and embryo in place inside the egg.  They’re the white twisted bits in the egg white.  (Totally amazing!  Shock absorbers, insulation, springs and stabilizers!)
  • Inner Shell Membrane:  the first of two membranes that hold the embryo-yolk-albumen together
  • Air Space:  Between the inner and outer shell membranes the air space acts as a condenser for moisture exchange.  This is where the baby bird takes its first breath before hatching.
  • Outer Shell Membrane:  The final packaging before the shell is laid on.  It’s attached to the shell when you crack open an egg.
  • Shell: The female’s uterus deposits calcium on the outer shell membrane to make the hard enclosure for the egg.  The shell has microscopic pores to allow air exchange for the developing embryo.
  • Cuticle:  A thin layer on the shell that adds protection.  The cuticle has caps on top of the pores that close when necessary to protect the embryo.

Eggs have the tools and potential to become baby birds.  Next week I’ll show you how.

(illustration from Wikimedia Commons; click on the image to see the original. Today’s Tenth Page is inspired by page 420 of Ornithology by Frank B. Gill.)

Videos of First Hatchling at Pitt

Thanks to @PittPeregines we have video of the first peregrine hatchling at the Cathedral of Learning

The video above shows the time from first pip (hole) in the shell until the chick hatches and dries out, white and fluffy beneath Dorothy’s breast.

The video below shows the first feeding and E2 arriving to meet the chick and spend some time with it.

Follow @KStJBirdblog (me) and @PittPeregrines (Dorothy & E2) on Twitter for updates.


(videos by @PittPeregrines constructed from National Aviary falconcam snapshots)

First Egg Has Hatched at Pitt!

First egg hatched at Cathderal of Learning, 25 Apr, 6:25am (photo from the National Aviary Falconca)

Dorothy and E2’s first egg has hatched at the Cathedral of Learning (approximately 6:25am).

Good morning, Dorothy and baby!

Watch for the first feeding and E2’s moment to meet his first hatchling of 2013.



6:36am:  A peek at the tiny baby (white fluffy near the eggs; you can see his beak).  Also look at the dark egg with the white seam near Dorothy’s foot.  It’s getting ready to hatch.
First hatchling just visible among the eggs (photo from the National Aviary falconcam at Univ of Pittsburgh)


(photos from the National Aviary falconcam at University of Pittsburgh)

It Won’t Be Not Long Now

One egg will hatch very soon (photo from the National Aviary falconcam at the University of Pittsburgh)

Look at the big hole in the egg on the left (Wed, 7:10pm).  It won’t be long now.  That one may hatch tonight.

Hammer away, babies!

Update, Thursday April 25, 6:19am
Dorothy is covering all the eggs and I don’t see a discarded shell so the first one hasn’t hatched yet.  Except… what is she looking at below her?  It sure looks like a broken shell.

Is Dorothy looking at a cracked shell? (photo from the National Aviary falconcam at Univ of Pittsburgh


(photo from the National Aviary falconcam at University of Pittsburgh)