Archive for the 'Birds of Prey' Category

Oct 26 2015

Up Close With Saw-whet Owls

Northern Saw-whet Owl at Project OwlNet Banding, 21 Oct 2015 (photo by Doug Cunzolo)

Northern Saw-whet Owl at Project OwlNet Banding, 21 Oct 2015 (photo by Doug Cunzolo)

Did you know that tiny owls are passing through Pittsburgh right now?

Northern saw-whet owls are 7-8″ long, weigh little more than a robin, and have big yellow eyes.  They live in wooded habitats where they’re fierce predators of white-footed and deer mice.  Though small (and cute) they have “attitude.”

Close up of northern saw-whet owl (photo by Bob Mulvihill)

Close up of northern saw-whet owl (photo by Bob Mulvihill)

From mid October to December saw-whet owls migrate at night from their breeding grounds in southern Canada and the northern U.S. to points south.  Each one travels alone but not very fast.  Individual owls average 10km (6.2 miles) per night and tend to reuse the same route year after year.  Every four years the species irrupts in large numbers.

We know this because of Project Owlnet, a continental network of researchers investigating owl migration, founded by owl researcher David Brinker in 1994.  In 2011 Brinker analyzed 10 years of fall banding data (81,584 owls banded!) and published his findings in The Wilson Journal of Ornithology.   Click here to read the fascinating results.

Pittsburgh joined Project Owlnet in Fall 2013 thanks to ornithologist Bob Mulvihill of the National Aviary.  Each Tuesday, Thursday and Saturday night from mid October to early December — weather permitting — Bob and his volunteers set up mist nets and play the owl’s call from dusk to midnight at Sewickley Heights Borough Park.

Bob Mulvihill holds a saw-whet owl for banding (photo by June Bernard)

Bob Mulvihill holds a saw-whet owl for banding (photo by June Bernard)

Pittsburgh’s not a main migration corridor so there are nights when no owls show up but it’s exciting when they do.  Thursday October 21 was quite a success as Bob wrote on Facebook,

Our second night of owl banding produced our second owl of the season! And lots of folks on hand to be delighted by it! A few Orionid shooting stars, a continually calling Barred Owl, and a couple of coyotes howling in the distance made for another “Who knew urban ecology could be so wild!?” kind of night.

You’re welcome to attend Pittsburgh’s Project Owlnet. Dress warmly (bring a blanket!) and show up any time.  Be sure to read more here before you go!

Now’s the time to see saw-whet owls up close.


p.s. If you can’t make it out to the park you can still support the project by “adopting” a saw-whet owl on the National Aviary website.  Click here to read more.

(photo of owl in hand by Doug Cunzolo, photo of owl face by Bob Mulvihill, photo of Bob Mulvihill with owl by June Bernard)

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Oct 16 2015

Young Eagles Eat Junk Food

Juvenile bald eagle hunting in Florida (photo by Chuck Tague)

Juvenile bald eagle hunting for fish (photo by Chuck Tague)

For juvenile bald eagles the first year of life is the hardest.  Fresh from the nest where their parents fed them, they’re off on their own hunting for food with almost no practical experience.  Every day is a new challenge.

The first order of business is Learn To Fish, but that’s easier said than done. Fortunately they have other options. They can munch down on carrion, grab food from others, or even eat junk food.

Junk food?

In the September issue of The Journal of Raptor Research the Center for Conservation Biology (CCB) analyzed the daily movements of 64 satellite-tagged bald eagles in the Chesapeake Bay region with an eye on their use of landfills.  With five years of data and 72 landfills the study found some interesting stuff.

A flock "Down in the dumps" at a Florida landfill (photo by Chuck Tague)

“Down in the dumps” at the landfill (photo by Chuck Tague)

For starters, 10% of the landfills were really popular and garnered 75% of the bald eagles’ use.  The landfills closest to eagle roosts were the favorites.  I imagine eagles like the convenience of a breakfast or bedtime snack.

Landfill use was much more common among the young.  Compared to adults, hatch year bald eagles visited 6 times as often, second year birds 4 times as often, and third/fourth year birds 3 times as often as adults.  Even so, there were individuals in various age groups who were obviously hooked.

It appears that bald eagles give up the landfill habit as they get better at fishing.

Junk food is for the young. 😉

Read more about the eagle study here at the Center for Conservation Biology.


(photos by Chuck Tague)

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Sep 25 2015

Bald Eagle Takes Selfie on Stolen Camera

Bald eagle screenshot from Mason Colby's video on YouTube

More than a year ago Mason Colby decided to film bald eagles in Craig, Alaska by setting up his Go Pro camera next to some salmon heads.

Things were going well until an immature bald eagle stole the camera!  Mason wrote on YouTube:

Set up my go pro next to some salmon heads from the days catch to film the eagles eating and next thing I know, one of them swoops down and snags the camera right off the ground. It carried it up to a mile away and I lost sight of it. For four hours we searched in the rain until I finally found it and the camera was still intact. So glad I got the footage!

Click on the screenshot to see what happened.


(screenshot from Mason Colby on YouTube. This video was featured by JunkinVideo on 3 Sept 2015)

p.s. Bald eagles are more plentiful and gregarious in Alaska than in Pennsylvania except for this once-a-year exception: They congregate at Conowingo Dam on the Susquehanna in November, just south of PA in Maryland.

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Sep 24 2015

Just Plain Ornery

Sharp-shinned hawk atCrooked Creek, October 2014 (photo by Steve Gosser)

Sharp-shinned hawk at Crooked Creek, fall 2014 (photo by Steve Gosser)

Throw Back Thursday (TBT):

Broad-winged hawk migration is about to peak in Pennsylvania. Perhaps it already has.

Next on the Hawk Watch docket will be lots of sharp-shinned hawks, showing off their attitude as they fly.  The peaceful camaraderie of the broad-winged kettle is not for them.  Sharpies are just plain ornery!

Read about their attitude in this September 2008 article –>  Ornery


(photo by Steve Gosser)

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Sep 14 2015

In Powered Flight

Merlin, eastern US (photo by Wm.H. Majoros via Wikimedia Commons)

Merlin, eastern USA (photo by William H. Majoros via Wikimedia Commons)

This year in Maine I was lucky to see two merlins (Falco columbarius), each one a fleeting glance as the bird zoomed by on a mission.

The first one zipped past the Cadillac Mountain Hawk Watch, pumping his wings the entire time.  We watchers had to think quickly.  His shape said “Falcon,” his size and dark color said “Not kestrel,” his powerful flapping said “Merlin!”  He was gone before we could say his name.

Merlins rarely pause and almost never soar.  Their flight style is a constant powerful flapping and they’re always very fast.  Compared to merlins, peregrines seem laid back and almost lazy.  Peregrines conserve energy for the split second when they need it.  Merlins burn energy all the time except for the moments they perch.

My second merlin offered a good comparison to a peregrine.  At low tide I visited the South Lubec sand flats to watch shorebirds.  A peregrine and merlin showed up to eat them.

The peregrine hazed the sand bar until all the flocks were airborne in tight evasive circles.  Then he flew through the flocks until he separated a bird alone and grabbed his dinner on the wing. He stopped to eat it on an island in the bay.

The merlin came out of nowhere.  Using the grass and goldenrods as a blind he pumped fast, low, and straight along the water’s edge.  The shorebirds were so surprised that most had no time to fly.  The merlin caught a slow bird and just kept going.  In powered flight, he didn’t stop to eat.


(photo by William H. Majoros, Creative Commons license via Wikimedia Commons. Click on the image to see the original)

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Sep 05 2015

Today Is International Vulture Awareness Day

Turkey vulture in flight (photo by Chuck Tague)

Turkey vulture in flight (photo by Chuck Tague)

Today is International Vulture Awareness Day, the day when we remember vultures under threat and thank them for saving us from disease.

International Vulture Awareness Day, 2015 logo

Originally founded by Birds of Prey Programme in South Africa and the Hawk Conservancy Trust in England this annual event teaches the benefits of vultures and our actions that threaten them.

The most famous vulture crisis happened at the turn of this century when public health officials, conservationists, and birders became alarmed that 95% of the vultures in India, Pakistan and Nepal had died-off in only 15 years.  It was the fastest bird decline in history and became painfully obvious when the landscape was swamped by decaying animal carcasses.  Research revealed that the solution was rather simple: Ban diclofenac, a painkiller given to cattle that’s deadly to vultures.  The drug was banned in 2006 but vulture populations are severely damaged — down 99.9% — perhaps irretrievably.

Vultures in Africa and Europe are declining as well and could face extinction within our lifetime.  In Africa the threats are complex; click here to learn more.

If you think our vultures are secure, think again.  The largest land bird in North America, the California condor (Gymnogyps californianus), is a vulture and is so critically endangered that they’ve been captive-bred since 1987.  Every California condor you see today comes from that program.

California condor in flight (photo from Wikimedia Commons)

California condor in flight (photo from Wikimedia Commons)

And in South America Andean condors are near-threatened.  You can see and learn about them at Pittsburgh’s National Aviary.

Thankfully our turkey and black vulture populations are stable, but we often don’t realize the good work they do for us.  They usually eat carcasses before we smell them and save us from the diseases harbored in rotting meat.  Did you know vultures can eat anthrax safely because their powerful stomachs protect them?  Thank you, vultures!

So when you see a vulture today give him a nod and thank him for his efforts.

Happy International Vulture Awareness Day!


(turkey vulture photo by Chuck Tague)

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Sep 04 2015

Well Over 1,000 Birds

Broad-winged hawks are on the move.  By the middle of this month their numbers will peak at Pennsylvania hawk watches.

In summer broad-winged hawks are secretive but by late August the birds have finished breeding and are ready to start their journeys to Central and South America.

Unlike most raptors, broad-wings travel in flocks, rising together in thermal updrafts, gliding out toward their destination.  At the bottom of the glide they find another thermal and rise again.  From a distance they look like rising bubbles so the flock is called a “kettle.”   The video above shows them gliding. Click here to read more about kettles.

Thermal updrafts are best over sun-heated land so the hawks avoid flying over lakes and oceans.  As they move south, the flocks grow in size and become concentrated at the northern edges of the Great Lakes and the Gulf of Mexico.  By the time they reach South Texas there are hundreds of birds per kettle and half a million broad-wing hawks per day.

To really see the sky filled with birds, visit the hawk watches at Corpus Christi, Texas or Veracruz, Mexico’s River of Raptors in the last week of September and the first week of October.

The video below shows broad-wings over Corpus Christi.  One kettle contains well over 1,000 birds!


(videos from YouTube. Click on the YouTube logo to see more information about the video)

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Aug 10 2015

Ospreys Getting Ready To Go

Immature osprey flying over the Duquesne nest (photo by Dana Nesiti)

Immature osprey flying over the Duquesne nest, 19 July 2015 (photo by Dana Nesiti)

The nesting season is over for most ospreys in Pennsylvania and some are already on the move.

In early August young ospreys stay close to home and practice their fishing skills under dad’s watchful eye, but it’s likely their mother has already left on migration.  This osprey family in Duquesne, PA is a case in point.

On July 19 Dana Nesiti photographed them when only two had fledged and their activity was still centered on the nest.

Immature osprey coming in for a landing at the Duquesne nest (photo by Dana Nesiti)

Immature osprey landing at the Duquesne nest while mom & siblings watch, 19 July 2015 (photo by Dana Nesiti)

When Dana returned on July 25, all three had fledged and competition had intensified for their parents’ handouts.  Below, the youngster at right has food while two others squabble over a fish. The bird on the far left grabbed his sibling by the wing to pull him away. “Give it to me!”

"Give it to me!" juvenile osprey grabs his sibling's wing to get the fish (photo by Dana Nesiti)

“Give it to me!” juvenile osprey grabs his sibling’s wing to get the fish, 25 July 2015 (photo by Dana Nesiti)

The winner flew off with the live fish.

Juvenile osprey flies off with the prize -- a live fish (photo by Dana Nesiti)

Juvenile osprey flies off with the prize: a live fish, 25 July 2015 (photo by Dana Nesiti)

But now more than two weeks later, the nest is not the focal point and the family will be hard to find.

Ospreys live in family groups during the breeding season but otherwise live alone.  The family starts to break up shortly after the young fledge.  Mom leaves before the kids are independent while dad stays behind to feed them for 10-20 days or more.  When the youngsters are self sufficient they leave, too.  Finally their father departs, 7 to 39 days after his lady left town.

Because they eat live fish North American ospreys don’t dare to linger where the water will freeze.  They spend the winter in Central and South America and the Caribbean, each at his own favorite place.  The adults won’t meet again until they return to their breeding territory.  The juveniles will stay south for two to three years before they come north to breed for the first time.

After this family has left Duquense we’ll see other ospreys passing through but “our” birds will be gone until next spring.


(photos by Dana Nesiti)

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Jul 24 2015

Learn About Burrowing Owls

This week a cute video of burrowing owls in Florida went viral on the web and prompted some questions about these adorable raptors.

Where do burrowing owls live?  What do they eat?  Was the Florida video taken in the wild?

Burrowing owls (Athene cunicularia) range from North to South America in dry, open areas with short vegetation and no trees.  In the U.S. they live year-round in Florida, the Southwest and California and breed in the Western dry plains and high plateau.

These owls need wide open spaces but are not picky about humans nearby.  They’ll happily dig or take over an existing burrow in remote locations as well as parks, vacant lots, pastures and campuses (Florida Atlantic University).  So yes, that video in Florida with people in the background was taken in the wild.

Burrowing owls eat insects, rodents, snakes and whatever they can catch, but they are small so they are wary.  They look cute when they stand tall but they’re actually watching for large raptors and mammals that might eat them.

How small are they?  The video above shows a research project last summer at Boise State University in which the students learn to hold, measure and band the owls.  What a privilege to learn about burrowing owls up close!

Don’t miss the end of the video when the owlets are released near their burrow.  Yes, they really are cute.


p.s.  Click here if you haven’t seen the Florida video.

(YouTube video from Boise State University, Boise, Idaho)


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Jul 13 2015

Father-Daughter Pair in Norfolk

'Dad' and 'tHE Missus', Norfolk, Virginia (photos by Mike Inman, used by permission)

‘Dad’ and his mate ‘HE’ in Norfolk, Virginia, 2015 (photos by Mike Inman used by permission)

In a recent Peregrine FAQ I described how peregrine falcons are not social creatures like we are.  In fact most raptors don’t hang out with their relatives, so that siblings from different years and birds separated by more than one generation can’t know that they’re related.

Since they don’t know their relatives, how do raptors avoid interbreeding?  By traveling.

Young raptors naturally disperse far from home and females typically travel twice as far as males, thereby mixing the gene pool.  Here’s how far some of Pittsburgh’s peregrines traveled from where they were born:

  • Downtown Pittsburgh: Louie dispersed 2.3 miles, Dori traveled 93 miles from Akron, Ohio
  • Cathedral of Learning: E2 dispersed 2.3 miles, Dorothy traveled 450 miles from Milwaukee, Wisconsin
  • Neville Island I-79: Beau dispersed 10.7 miles, Magnum traveled 79 miles from Canton, Ohio

Bald eagles are much more social than peregrines. They fish and roost together in early winter but when it comes time to breed they disperse far and wide.  Close interbreeding among bald eagles is rare.

That’s why it was such a surprise to discover that this year’s pair nesting near Norfolk Botanical Garden is father and daughter.

The male is not banded but he has a unique tiny black dot in his left iris, called an inclusion, that’s visible in good photographs. This identified him as the 25-year-old male that used to nest in the Garden.

His mate is banded with the code “HE,” a band she received six years ago when she was a nestling at Norfolk Botanical Garden.  Yes, she’s his daughter.

Their close relationship was reported this spring by the Center for Conservation Biology (CCB) that monitors bald eagles in Virginia and banded “HE” in 2009.   CCB’s blog article provides details and photos.

It’s unusual for a female to settle so close to her birthplace but this location has had many challenges.  After the old female was killed by an airplane at nearby Norfolk International Airport in 2011, eagles were no longer allowed to nest at the Garden.  The male and all his potential mates were harassed away.  Nine nests were destroyed.  All the females left. The male didn’t nest for three years.  (Click here for the story.)

Unusual as this pairing is, the good news is that he finally found a mate, they found a safe place to nest, and together they fledged one eaglet on May 29.

It all worked out in the end.


(photos of the NBG pair courtesy of Mike Inman,

p.s. As part of their monitoring efforts CCB recently identified a female bald eagle with an unusual story. Click here to read about ‘Dolly’, born at the Birmingham (Alabama) Zoo to injured, unreleasable parents, she now nests along the James River in Virginia.

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