Archive for the 'Nesting & Courtship' Category

Apr 03 2014

Three Eaglets … For Now

Third bald eagle egg hatches at the Hays nest (snapshot from the Pittsburgh Hays eaglecam)

Yesterday afternoon around 5:00pm the third and final egg hatched at the Pittsburgh Hays bald eagle nest.  This happened during rush hour so a lot of us missed it … or did you stay late at work to watch?

Click on the photo above to watch the eaglet emerge from his egg.

An hour later all the eaglets are visible as Mom feeds the oldest chick.

Her actions reminded me that we will soon see a characteristic of bald eagle family life that’s quite different from peregrines’ –  the tendency for the oldest eaglets to thrive and the youngest to die, sometimes killed by their siblings.

Bald eagle eggs hatch asynchronously so each new eaglet is two days smaller than the previous chick.  Bald eagle parents feed the chick that asks for food, and since the oldest is bigger and more active he’s fed more than his siblings.  Eagle chicks are aggressive toward their siblings and the parents don’t breakup the fights.  The third chick often starves.  Cornell’s Birds of North America Online describes it this way, referring to a study in Saskatchewan:

Hatching asynchrony and differential growth leads to differential mass in siblings, facilitating competition and fratricide. Sibling competition and mortality is greatest early in nestling period, when size differences are greatest. Third-hatched chicks in Saskatchewan nests received little food and usually starved.

This behavior is quite different from the peregrines’ lifestyle.  Peregrine falcon eggs hatch almost simultaneously so all the chicks are close in age and size.  The last chick may be smaller at first because he hatches two days later, but peregrine chicks are not aggressive and their parents make sure everyone eats at every feeding.   Mother peregrines “chup” to their babies to encourage them to stand up and be fed.  Click here see how effective (and cute) this is.

For now there are three eaglets at the Pittsburgh Hays eaglecam … but be prepared for the day when there might be only two.

 

(videos and snapshots from the Pittsburgh Hays eaglecam)

30 responses so far

Apr 01 2014

A Threat To Bald Eagle Nests

Aerial photo taken after a logging operation along the Rappahannock River cut an eagle nest tree. This forest block supported a bald eagle nest for ten years prior to the harvest. Photo by Bryan Watts. (linked from The Center for Conservation Biology)

 

The Internet is captivated by the Hays bald eagle family nesting on a wooded hillside in Pittsburgh.  Their nest is protected by the Pennsylvania Game Commission and worldwide media attention, but what happens to nests that aren’t so famous?  Here’s the story of an unexpected consequence of removing bald eagles from the federal endangered list.

For 40 years bald eagles were completely protected by the Endangered Species Act (ESA) and everyone understood not to harm them.  By 2007 the birds made such a great recovery that they were removed from the federal ESA listing. Fortunately they are still protected by a law of their own, the Bald and Golden Eagle Protection Act that protects eagles, their eggs and their nests.

The Center For Conservation Biology (CCB) in Williamsburg, Virginia monitors bald eagle nests in the Chesapeake Bay area where 75% of the nests are on private land.  Each spring they fly over the watershed twice: once to count occupied nests, later to count chicks.  Last month CCB reported what they’ve found after 6+ years without ESA protection:  a real increase in the number of eagle nest trees cut down.

Bald eagles use same the nest for many years so when CCB flies over the area in early March, they look for known as well as new nests.  Increasingly they find former nest trees are gone, cut down when an area is wiped out by a large logging operation like the one above.

Private landowners apparently don’t realize the Eagle Act protects the nest, so the well-publicized de-listing of the bald eagle has lead to an unintended consequence:  disregard for the eagles’ habitat and nest trees.  CCB points out that education of landowners is sorely needed.

Click on the photo above to read the full story at The Center For Conservation Biology.

 

(photo of a clearcut along the Rappahannock River in Virginia, linked from The Center For Conservation Biology blog.  Click on the image to read the article)

2 responses so far

Mar 31 2014

Four Celebrities

Pittsburgh's Hays Bald Eagle family, 30 March 2014, 2 parents, 2 chicks, 1 remaining egg (photo from the Hays eaglecam)

Yesterday was a big day for the Pittsburgh Hays bald eagle family.  Their second eaglet hatched just after dawn, and the whole family was featured on ABC World News with David Muir.

Above, both parents feed the chicks on Sunday afternoon.

Click here for the ABC news segment.

Their third and last egg is due to hatch April 1.

Watch them “live” on the eaglecam.

 

(photo from the Pittsburgh Hays eaglecam)

No responses yet

Mar 29 2014

Eaglet’s Parents Celebrate

First eaglet of 2014 at Pittsburgh's Hays bald eagle nest, 28 March (snapshot from the eaglecam)

There he is, the first eaglet of 2014 at the Pittsburgh Hays bald eagle nest.  He’s hard to see because he matches the nest, hence the arrow.  The two remaining eggs and his discarded eggshell (closest to Dad’s beak) stand out.

This tiny gray ball of fluff emerged on a warm and windy afternoon, March 28, under his mother’s gaze.  As soon as he was dry she brooded him until Dad returned with food.

Click on the snapshot above to watch “Hays Parents Celebrate Hatch.”  Dad has brought a fish to share.  While Mom eats, Dad studies the eaglet. “Is he hungry?” Not yet, so Dad rearranges the nest.  Mom leaves on a well-deserved break and Dad settles down to brood the chick.

Bald eagles brood their nestlings during cold and inclement weather until they’re about four weeks old.   In the first week the brooding is almost constant because the nestlings can’t regulate their own body temperature.  This also serves the dual purpose of incubating the unhatched eggs while keeping the eaglet(s) warm.

The next egg is slated to hatch on March 31.  Watch the eaglecam to see.

 

p.s. Don’t forget you can also see the eagles in person today (March 29) on the Three Rivers Heritage Trail with the National Aviary’s Bob Mulvihill, 9:00am to noon.  Click here for more information.

(snapshot from Pittsburgh Hays Eaglecam, broadcast by WildEarth)

No responses yet

Mar 28 2014

The Eaglet Has Landed!

The first eaglet of the season hatched today in the Pittsburgh’s Hays Bald Eagle nest at approximately 2:30pm.  In this YouTube video captured by PixController you can see the baby bird next to two eggs and his own eggshell.  Then mom comes over to help.

Watch him on camera here at PixController or here on the National Aviary website.

Media Attention:  He’s already a celebrity!

Festivities tomorrow!    March 29, 9:00am to noon, watch the nest at Hays — in person!

National Aviary Ornithologist Bob Mulvihill will be at the Hays Bald Eagle nest site tomorrow morning from 9 a.m. until noon with the spotting scope donated by Wild Birds Unlimited! Feel free to stop by for a really good look at the nest, maybe even catch a glimpse at what’s going on IN the nest!
Parking is available courtesy of Keystone Iron and Metal Co. in their employee parking lot at the end of Baldwin Road (see map), or use the address 4901 East Carson Street into your GPS!
The viewing site is a short distance from there: carefully cross the railroad tracks and turn left onto the trail. Bob will be about 200 feet down the trail with the spotting scope!
Click here for a map of how to get there.

Thanks to the PA Game Commission and PixController for bringing this eagle family up close.

 

3 responses so far

Mar 25 2014

Mad, Mad Mergs

Three male red-breasted mergansers pursue a female

Red-breasted mergansers already look a little crazy because of their wild head feathers.  Here you see they’ve really gone nuts.

In this photo by Pat Gaines three male red-breasted mergansers are courting one female. The guys zip around and churn the water like jet skis, abruptly halt and point their bills skyward, dip their necks and crowd around her.

The lady doesn’t look like she wants this much attention.  Pat wrote that she flew away pursued by all three males and concluded, “So this is what it must be like for a beautiful woman at a singles bar.”

Click on the photo for a closeup and here for a video of their courtship behavior.

 

(photo by Pat Gaines on Flickr, Creative Commons license. Click on the image to see the original)

p.s. Notice how the feathers around the female’s eye form a dark circle.  It looks like she hasn’t slept in weeks.  ;)

No responses yet

Mar 18 2014

Why Hooded Mergansers Have Hoods

March is the month for duck migration and a great time to watch them courting.

I mentioned last Thursday that common goldeneyes have an unusual courtship display.  So do hooded mergansers.

The males pump their heads, raise their crests, toss their heads forward as if to unfurl their hoods, and waggle their heads side to side.   “Look at my white crest!”

They also throw their heads back and point their beaks to the sky.  As they bring their heads upright they say “Merg-merrrrrg!”  Listen to the video.  They sound like frogs!

So why does the hooded merganser have a hood?  Relentless female selection.  The ladies are so impressed by a good head toss that they pick the guys with the biggest, whitest hoods.  The guys with little hoods never have kids.

“The better to impress you, my dear.”

 

(video by Kathleen Fry on YouTube)

p.s. When they’re not courting hooded mergansers often keep their crests down. Click here to see what a difference the hood makes.

No responses yet

Mar 12 2014

Two Eggs At Gulf Tower

Dori with two eggs, 12 March 2014, 3:30pm (photo from the National Aviary falconcam at Gulf Tower)

Dori laid her second egg at the Gulf Tower in downtown Pittsburgh around 3:00pm EDT today.  She kept it sheltered because it’s been raining hard all day.

 

Above, Dori looks at her two eggs while Louie has gone to prepare a meal for her.  Below he shows her what he’s caught –  something small, dark and wet.

Louie brings food for Dori after she laid her second egg (photo from the National Aviary falconcam at Gulf Tower)

(photos from the National Aviary falconcam at the Gulf Tower)

 

——————————————————————————–
p.s.  Meanwhile at Pitt, Dorothy looks like she’ll lay an egg any minute now… except she didn’t…
Dorothy looks as if she'll lay an egg any minute now, 12 Mar 2014 (photo from the National Aviary falconcam at Univ of Pittsburgh)

5 responses so far

Mar 11 2014

Rubber Necks

 

This month while the ducks are stalled in Pennsylvania waiting for northern lakes to thaw, they spend their time courting.  Some species merely chase the ladies.  Others have elaborate displays.  My favorite is the common goldeneye who tosses his head so far back it looks as if he’ll hurt his neck.

In this video two male goldeneyes (blue-black iridescent heads with white face patches) show off for two females (brown heads).  The males raise or lower their head feathers to make their heads look round or flat.  When they toss their heads their feathers are raised and their heads look enormous.  The gesture is not enough.  They also make a rattling peent, “Look at me!”

If the lady likes what she sees she swims with head and neck outstretched as if she’s dipping her neck in the water.  This suggests her posture during copulation so if course it keeps the action going.

“Do that again,” she says, “Toss your head for me.”

I swear they have rubber necks.

(video by slpatt on YouTube)

No responses yet

Feb 20 2014

First Eagle Egg!

Spring is coming!  The bald eagles at Hays in the City of Pittsburgh laid their first egg yesterday at 4:45pm!

This the second year the eagles have nested in Hays but the first time we’ve been able to see inside the nest thanks to PixController’s streaming eaglecam and the PA Game Commission’s permission and site assistance.

The egg was immediately breaking news (no pun intended) at the Post-Gazette, Tribune Review, WPXI and KDKA to name just a few.

In this video of the egg’s first on-camera appearance notice the reactions of ‘Ma’ and ‘Pa’ eagle…

  • The video begins with the mother eagle standing over her egg, waiting for it to dry.  Her tail is spread and she’s holding her wings open to shelter the egg without touching it.
  • When the egg is dry, she gently rolls it with her beak and keeps her talons folded in as she steps near the egg. She is very careful.
  • Just before her mate arrives you can hear his “whee” call announcing his arrival.
  • Notice how much bigger the female is than her mate.  This size difference is normal in birds of prey.
  • Both eagle parents rearrange the sticks, mosses and grasses in the nest.  If you watch peregrine falconcams you’ll notice that peregrines don’t use sticks so there’s nothing to adjust. Watch closely and you’ll see peregrines rearrange the rocks.
  • Though the eagles are nesting on an extensive wooded hillside above the Monongahela River, the river banks hosts two active railroad tracks and a scrapyard.  That’s why you hear mechanical and industrial sounds on the camera.

You can watch the eaglecam at several websites. My two favorites are PixController and the National Aviary.  Click on a logo below to watch the Pittsburgh eaglecam.  PixController’s has a link to the video archives.

PixController logoNational Aviary logo

 

(video from Bill Powers at PixController)

No responses yet

« Prev - Next »

Bird Stories from OnQ