Yearly Archives: 2012

They’re Here Somewhere

Peregrines
View of Pittsburgh from Mt. Washington tower (photo by Shane Cooper)
View of Pittsburgh from Mt. Washington radio tower (photo by Shane Cooper)

Pittsburgh’s downtown peregrines have not courted at the Gulf Tower nest since March 1.  Even then they were largely absent in January and February when they should have been visiting the site more often.

What happened?

Peregrines are extremely faithful to successful nest sites but they will leave if they feel the location is no longer safe for raising their young.  In a city, humans walking above them, construction on the floors above or near their nest, or faces peering at them from indoors will send them away.

Construction had been going on at the Gulf Tower until quite recently.  Perhaps that’s why the peregrines are missing, though we will never know.

We do know Dori and Louie have not left Pittsburgh.  One of them flew past the Gulf Tower yesterday and they’ve been seen on the Monongahela River side of town.

For peregrines, biology rules in March.  In our area there’s a three week window when they typically begin laying eggs:  March 10 to April 2.  By April 2 the first clutch has begun.

So where are Dori and Louie now?

Downtown is their territory.  They’re here somewhere.

(photo by Shane Cooper.  Click on the photo to see the original.)

 

Eye Ring

Beyond Bounds
Silvereye in Tasmania (photo from Wikimedia Commons)

Here’s a very small bird with a very large eye ring.

Native to Australia and New Zealand, he’s a migratory bird called a silvereye (Zosterops lateralis).   He’s only the size of a kinglet.

This month in the southern hemisphere silvereyes are gathering in flocks because winter is coming.  They’ll fly north to warmer climates eating fruit along the way.

Here’s a video of them preening after a bath.

The eye ring is amazing…

(This photo by JJ Harrison was Picture of the Day on Wikimedia Commons 23 March 2009)

Juxtaposition: Too Early Spring

Phenology, Plants & Fungi
Bloodroot, Barking Slopes, 25 March 2012 (photo by Kate St. John)

26 March 2012

Yesterday I hiked at Barking Slopes to see what was blooming after 11 days of June-like weather.

So many flowers had opened that the ground was carpeted with them. Squirrel Corn (Dicentra canadensis), Dutchman’s Breeches (Dicentra cucullaria), Spring Beauties (Claytonia virginica) and Cut-leaved Toothwort (Cardamine concatenata) were all at their peak.

So were Bloodroot (Sanguinaria canadensis, above) that normally blooms in late March and Large-flowered Trillium (Trillium grandiflorum, below) that normally blooms in late April.

It was an odd juxtaposition of two flowers that never bloom at the same time.

Large-flowered Trillium in bloom, Barking Slopes, 25 March 2012 (photo by Kate St. John)

Tonight we’ll have a killing frost. The March flowers may be able to cope but I doubt the April flowers will survive.

(photos by Kate St. John)

More Eggs To Come

Nesting & Courtship, Peregrines

It’s an hour before dawn and Dorothy is sleeping on the perch in front of her nest.  (See her at the left edge of the photo.)

The fact that she isn’t incubating her eggs indicates she will lay at least one more, possibly two.

Peregrines don’t begin incubation until their clutch is nearly complete.

So we’ll have a couple more days of egg-watching …  and then she’ll begin The Big Sit.

Update, March 25, 10:00am:
Looks like Dorothy and E2 have begun incubation. One more egg? Two?

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

Feats of Engineering

Birds of Prey, Nesting & Courtship

If you look up at the corner of Fifth and Craig these days it’s hard not to notice a pair of red-tailed hawks swooping around St. Paul Cathedral.

After two weeks of testing other sites the local red-tails have chosen the west steeple of St. Paul for their 2012 nest.

They have a thing for buildings.  Though most red-tailed hawks nest in trees this pair has nested on buildings for years, most notably on the roofs at Central Catholic High School and Carnegie-Mellon Fine Arts.  Their “kids” are often rescued.  I recognize the female by her light brown head and her crazy love for bad nest sites.

Peter Bell couldn’t help but notice this when he stopped by with his camera on Thursday afternoon.  He was looking for peregrines and instead found the hawks yanking branches off nearby trees and carrying them to the steeple.  His photo below shows a hawk standing with sticks (red arrow) on a very narrow ledge — probably too narrow for a red-tail nest.

 

What do Pitt’s peregrines think of this development?  St. Paul is close to Pitt and a favorite hang out of their newly fledged young but so far Dorothy and E2 are unphased.  They know this red-tail pair is harmless.  They’ve  been neighbors for at least five years.

And this is the second time the red-tails have tried to nest at St. Paul.  Last year the experiment failed in a matter of days when strong winds blew the sticks off the steeple.

It will be interesting to see if they can pull off this feat of engineering.

(photo by Peter Bell)

Uh Oh! Too Early Spring

Migration, Phenology, Schenley Park, Trees
Oak flowers blooming 22 March 2012 (photo by Kate St. John)

23 March 2012

Welcome to Day 11 of June-in-March.  The heat feels nice, huh?  What could go wrong? As it turns out many things could go wrong.

Yesterday I found red oaks starting to bloom in Schenley Park a month ahead of schedule (photo above).  This should be happy but something is missing.  The rose-breasted grosbeaks aren’t here to eat them.

Long ago I learned from Chuck Tague that rose-breasted grosbeaks move north as the oaks bloom, perfectly timing their arrival to coincide with their favorite migration food — oak flowers.

Rose-breasted grosbeak (photo by Chuck Tague)

But right now the grosbeaks are in Central and South America, waiting to fly across the Gulf of Mexico to arrive in Pennsylvania in late April or early May.  They don’t know our oaks are blooming.  The flowers will be gone.

What will the rose-breasted grosbeaks do when they get here?

Uh oh!

(photo of oak flowers by Kate St. John. Photo of rose-breasted grosbeak by Chuck Tague)

Second Egg at Pitt!

Peregrines


Dorothy laid her second egg at 10:00am today but she exposed it only briefly, captured at this link by @PittPeregrines.

For two and a half hours she panted while she sheltered her eggs from the scorching heat — probably more than 85 degrees at the nest in full sun.
 

 

Finally at 12:21pm she showed us both eggs.  Then at 12:30pm E2 brought food and took his turn at keeping the eggs cool. 

Whew!  When will this heat wave end??

(photos from the National Aviary falconcam at the Cathedral of Learning)

 

 

Bonnies On The Move

Water and Shore
Bonaparte’s gulls in winter by Chuck Tague.

Bonaparte’s gulls are on the move.  Yesterday on PABIRDS Mark Vass reported a migrating flock resting on the Ohio River at Monaca and Scott Kinsey saw some at North Park.

I’ve only seen Bonaparte’s gulls in fall and winter so I imagine they looked like the birds in Chuck Tague’s photo above  — pale gray backs, long white triangles on the leading upper side of their wings, black bills and white heads.

But maybe not.

In the summer Bonaparte’s gulls lead very different lives.  Having spent the winter at the ocean they fly northwest to their breeding grounds in the taiga (boreal forest) of interior Alaska, north-central and western Canada.  There they nest in conifers.

And they change their appearance.  In breeding plumage they have black heads.  Perhaps this camouflages them while they sit on their nests in the trees.

Bonaparte’s gull on nest by Dr. Matthew Perry, Pawtuxent Wildlife Research Center, USGS

So I wonder what yesterday’s “bonnies” looked like.  Were their heads turning black?  Would they look familiar?

I think so.  I can always recognize them on the move by their delicate moth-like flight and the white leading edge on their upper wings.

(photo of Bonaparte’s gull flock in winter by Chuck Tague. Photo of Bonaparte’s Gull on nest by Dr. Matthew Perry, Pawtuxent Wildlife Research Center, USGS)