Outside My Window

…say this pair of ospreys from their nest at Shenango Lake in late May.  They already had babies and were wary of anything that might harm them.  Something overhead made them nervous.

Osprey nesting season varies across North America based on climate.  Osprey eat fish so they nest near lakes, bays, deep rivers and sheltered salt-water.  As with all birds, they migrate if their food supply is seasonal.  Fish migration (salmon and shad) and ice (which makes fish inaccessible) are determining factors.

Osprey reuse the same nest year after year by adding to the top of it, but they won’t return to the site until the ice is out.  In South Florida osprey don’t need to migrate so they begin nesting in November and December.  In southern New England, they nest in mid-to-late April because the ice doesn’t break until March.  Timing in Western Pennsylvania is similar to southern New England’s.

No matter where osprey nest, the process takes the same length of time:  37 days from egg-laying to hatch, 50-55 days from hatch to fledge, and 10-20 more days until the young are independent of their parents.   

By now, the babies from this Shenango Lake nest have flown and they’re learning the ropes of adulthood.  When the cold weather comes it’ll be their turn to go away.

(photo by Cris Hamilton)

Look closely under this mother’s breast feathers and you’ll see two babies, one of whom is yawning.

This common nighthawk is nesting on a roof and was found by Paul Leverington who owns a roofing business in Euclid, Ohio.  He’s also a fine photographer. 

Last month I wrote about the decline of common nighthawks, so I know how lucky Paul was to see one nesting.  A rare sight indeed!

(photo by Paul Leverington)

That’s a pretty good translation of what this bird is saying.

He’s 5-11 days old and spends a lot of time shouting for food. 

His noise would be a life-threatening disadvantage except that his nest is part of a community, so even if his parents are away collecting food there are other adults around to keep the colony safe.

At this age he looks wild and crazy.  His juvenal pin feathers are tipped with white down and his head is covered with rusty feathers.  At 24 days he’ll look a little less crazy and be walking so well that he won’t stay in his nest at all.  At that point he’ll be a few days away from fledging – and he’ll still be shouting.  

Fledging doesn’t shut him up.  He has to learn how to feed himself and will be almost 60 days old before he can do that on his own.  Two and a half months from egg to independence is a long time in the bird world.  Compare that to 25 days for a robin and his parents’ commitment is truly amazing.

So what bird is this?  He’s a tricolored heron. 

You won’t see this chick in Pennsylvania – they nest in Florida and along the Gulf Coast – but after the breeding season some birds fly north as far as Canada.  Tricolored herons hunt small fish by stealth so they have to leave before the ice comes. 

Pennsylvania is just a lark for a kid like him.  Yo!

(photo by Kim Steininger)

True to their name, tree swallows nest in hollow trees – or in the next best thing, bluebird boxes.

When they arrive in early spring, their first and most important activity is to find a nest hole.  Suitable nest sites are scarce, so tree swallows are aggressive about claiming them and will fight – even kill – another tree swallow of the same sex who dares to claim their nest hole.  At this stage it can get gruesome.  If a site has nestlings and the male dies, the new male may kill the widow’s young.  Females have been known to kill the young of others to make the site become available.  So much drama!

But there are other challengers who want nest holes.  House wrens, house sparrows and northern flickers will destroy tree swallow eggs and nestlings if they can.  Eastern bluebirds also want nest holes but they get along with tree swallows if two boxes are provided near each other, one for each species. 

Aside from nest site competition, tree swallows are very social creatures and tend to nest near each other if enough sites exist.  Once a site is selected the female builds a nest inside it and adorns it with feathers.  Even if she arrived weeks earlier, she waits to lay her eggs in May so the babies will hatch around June 1.  Both parents feed the young, making 10-20 trips per hour to keep those yellow mouths filled! 

Now it’s July and all the tree swallows are about to fledge.  Next month they’ll be on the move in large flocks, headed for Florida and the Gulf of Mexico. 

Watch them while you can.

(photo by Kim Steininger)

Last week I discovered an American robin nest outside my study window. 

As I sit here and type, Mother Robin is making food deliveries to her tiny babies who are slightly older than the chicks pictured here.  This is probably her second brood this season.  If her first nest was very early or if it failed, this could be her third.

Now she pauses to brood her babies.  As she sits on the nest she makes a high-pitched “eeeeeeeeep” sound.  It’s a sound I wouldn’t associate with robins if I hadn’t seen one making it.  Is she calling her mate? 

Her chicks are silent, a good defense against predators at this age.  Even so, Mother Robin is wary.  My cat sits at the window as I blog and the robin is alert to Emmy’s pointy ears.  I don’t think Emmy’s noticed the robin’s nest because it’s far away and hidden by leaves.  (I use binoculars to see the babies.)  My cat is much more absorbed by the house sparrows sitting on the wire shouting at her. 

I hope all goes well for this robin family.  There are crows, grackles and blue jays on my street who would love to raid her nest.  Good luck, babies.

(photo by Chuck Tague)

In case you haven’t heard, the Cornell Lab of Ornithology is collecting photos and stories of unusual nest locations – and there are prizes!

The contest is called Funky Nests in Funky Places.  Here’s one of them from their contest entry page.  Imagine nesting on a tire.

When I heard about the contest I couldn’t resist signing up the Don’t Walk Robin from last April.  Remember her?  She was the one who nested on a Don’t Walk traffic signal.  Not only did I make her famous here on the blog but she’s now Entry #107 in the contest.

Last night I looked at the contest entries online and some of them made me laugh out loud.  The Don’t Walk Robin is a serious bird compared to Entry #5 who is nesting next to the words “Slam It.”  Check out Entries #38 and #50 while you’re at it on the Funky Nest Entries Directory.

(photo linked from Cornell University, Funky Nests in Funky Places)

If you’ve never seen one I’m sure you’re wondering… what the heck is this? 

It’s a Baltimore oriole’s nest, a bag of birds. 

If you look closely at the top of the nest you can see the tail and wing of the adult male.  His head and feet are inside the bag but his tail doesn’t fit.

Despite the leaf cover, these bags are noticable in western Pennsylvania right now because the baby birds are making a lot of noise inside.

Baltimore orioles are nothing if not noisy.  Only eight weeks ago the males came back to Pennsylvania, singing and chattering and claiming territory.  Soon the ladies arrived and the males displayed their beautiful orange feathers and made a lot of noise to attract their attention.  The females are impressed by this – and they’re noisy in return.  After they’ve chosen a mate, Baltimore oriole pairs stay in constant audio contact. 

Shortly after pairing up, the female Baltimore oriole builds her nest at the tip of a drooping tree branch.  It takes 5-8 days of weaving plant fibers, string, grape bark, grasses and pieces of old oriole nests to make this bag.  She doesn’t engage in skillful weaving but her random method works nonetheless. 

When she’s completed a hanging structure she lines it with feathers, soft grasses, wool, willow and dandelion fluff.  Her mate sings while she builds and she replies.  She then lays 4-6 eggs and incubates them alone for 12-14 days.  Her mate’s contribution is to sing nearby.  Lots of noise.

When the eggs hatch both parents feed the babies.  After about a week the nestlings take over in the noise department and become very vocal inside the bag.  I found three oriole nests at Schenley Park last week just by following the babies’ sound.  It’s usually a disadvantage for baby birds to give away their location but Baltimore orioles have always been noisy and it doesn’t seem to have to damaged their chance at survival.

As the nestlings get noisier their father sings less.  In 12-14 days they fledge and both parents feed them for about a week.  Then mom begins to molt and travels more widely.  Dad coaches the fledglings for a couple of weeks, then the youngsters disperse.  He stays on territory until he’s finished molting and leaves our area in late summer.

It all happens very fast.  From late April to mid-July there’s a lot of activity and then it’s over.  

Now’s the time to look for a noisy bag o’ birds.

(photo by Chuck Tague)

“What’s it like on the nestrail?” ask these peregrine sisters. “How come you can get up there and we haven’t been able to yet?” 

That’s what it looks like they’re saying as their brother comes down from the nestrail with his back to the webcam. (See that brown feathered back at the bottom of the picture?)

Today at lunch time Fledge Watch, Little Brother hopped up on the nestrail and walked all the way to the west end of it.  From Schenley Plaza we couldn’t see the nest but we had excellent views of Dorothy, his mother, making circles in the sky and Little Brother’s adventure. 

The sisters were watching too.  A co-worker who viewed the webcam while I was at Schenley Plaza said the sisters moved their heads as if they were at a tennis match. 

And get a load of the look on the face of sister #3 at the far left.  Apparently she doesn’t approve of ledge-walking.  Harumph! 

Come on down to Schenley Plaza and join us.

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

When peregrine nestlings are 33 days old what happens next? 

The things you see on the webcam might be confusing so here’s what to watch for as they get ready to fledge:

• They’re still babies and they still do ”baby” things.  Sometimes they sleep flat on their stomachs and throw their legs out to cool themselves.  They look like pancakes.  The adults don’t do this.
• Their parents are teaching them to feed themselves and will increasingly drop off food and let them tear it apart on their own.  The female chicks are 1/3 larger than their father by now so they dwarf him at feeding time.  No wonder he’s thinking of drop-offs!
• They flap their wings a lot without going anywhere.  This builds their wing muscles so they’ll be in good condition when they fly. 
• Sometimes they flap and run along the surface, just barely rising in the air.  It’s like using training wheels.
• They will WALK out of the picture.  They haven’t flown yet, they’re just exploring.  This is called “ledge walking.”  There’s a lot of territory near the nest and they need to learn about it.  When they’re ledge walking you won’t see them on camera but they are quite nearby. 
• They will perch right in front of – or on – the camera.  Incredibly cute.
• At the University of Pittsburgh there’s a perch on the building called “the keyhole” that their parents like to use.  It’s just to the left of the camera view.  Soon the youngsters will figure out how to jump the short distance from the green perch to the keyhole.  On the webcam it will look as if they leapt into thin air but from Schenley Plaza you’ll see that they’re in the keyhole.
• They will walk up the cement pillar at the back of the camera view or hop into the gully behind it.  When they do that they disappear from the cam but they still haven’t flown. 
• Soon they will find the perfect runway for flight practice which is up to the left of the camera view.  They will walk up the cement pillar or jump up to what we call “the nest rail.”  You won’t see them on camera but they’ll be easy to see from Schenley Plaza. 

Again, they haven’t flown yet.  This is “flying with the training wheels on.”

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

Here they are, cute as could be, on their banding day.  Now two of these peregrine chicks are dead and the third was found on the street.  What caused this chain of events?  Is the fourth chick in any danger?

Peregrine falcons have nested on the Brandywine building in Wilmington, Delaware since at least 2002.  My friend Kim Steininger, who works across the street, has followed their family life and taken pictures of them for years.  Her peregrine photos often appear on this blog.

Until last weekend it was a normal nesting season for the Wilmington peregrines.  They hatched four healthy chicks who were banded by US Fish and Wildlife Service (FWS) on May 18th.  At that time the family was in good health and so well fed that their crops bulged pink through their down.  There was no hint of what was to come.

After Memorial Day weekend two of the chicks were found dead at the nest.  The nest doesn’t have a web camera so no one knows what led up to it.  Were the deaths sudden?  Were the chicks sick for a while?  Were they harmed in a fight among rival adults?  Did they eat poisoned prey? 

Those who monitor the nest were saddened and determined to solve the mystery.  They wanted to retrieve the dead chicks and examine them for cause of death but the live chicks were too close to fledging and might jump to their deaths if people opened the access door.  The only thing to do was wait.

Then on Thursday the third chick was found on the street.  His flight feathers were not fully developed and he was clearly not ready to fledge so he must have fallen more than 200 feet to the ground.  He was taken to Tri-State Bird Rescue and given a complete medical exam including blood tests for disease and poison.  Maybe his condition would give a clue to the deaths of his siblings.

His test results were more than hopeful, they were excellent.  The blood tests came back negative, the bird is bright and alert and he had no injuries whatsoever – miraculous, considering his tumble to the street.  His adventure gave everyone hope and an opportunity to find out what happened to his siblings.

Today the team from Tri-State Bird Rescue will return this chick to the nest, collect the dead bodies and gather up prey remnants.  Craig Koppie of FWS advised them that the chick who remains at the nest is female and thinks she’s less likely to jump than her brother was.  Everyone will be very careful. 

The dead bodies and prey remnants will be tested for illness and poison. Soon, maybe soon, the mystery will be solved.

(photo of the Wilmington peregrine falcon chicks, 18 May 2009, by Kim Steininger.  Click on the picture or here to see her photos of their banding.)