Category Archives: Birds of Prey

Near Threatened Eagles: A Life Story

The amazing photo below of an eagle’s claw and a human hand left me wondering, Who is this bird and why are his claws so big? Today I’ll tell you a bit of his life story.

Juvenile crowned eagle in captivity (image from r/pics on Reddit)

Shaped like a giant goshawk with a feather crest, the crowned eagle (Stephanoaetus coronatus) lives in the riparian forests of sub-Saharan Africa where it eats monkeys, small forest antelopes (duikers), “mouse-deer” (chevrotains) and “rock rabbits” (rock hyrax). Click on the links to see photos of these unusual animals.

Crowned eagles weigh only 6-10 pounds, smaller than bald eagles, yet they routinely capture mammals twice as heavy as they are. Reports say they can fly with prey that outweighs them, but they normally rip it apart on the ground and cache pieces in the trees. For this lifestyle they need large talons.

Deforestation in Africa is destroying the crowned eagles’ high-canopy habitat and their population is declining. They are listed as Near Threatened by the IUCN.

African crowned eagle in flight (photo from Wikimedia Commons)

Fortunately they nest in safety at Zimbali Coastal Resort near Durban, South Africa. Watch them at the nest in Zimbali’s 8-minute video.

(photos from Wikimedia Commons, embedded Reddit post; click on the captions to see the originals)

Best Bird Of The First Day

Turkey vulture (photo by Melissa McMasters via Wikimedia Commons)

For many years now my First Bird of the Year is always the American crow because hundreds fly over my house before dawn, cawing as they disperse from the roost. The only way a different species could win “First Bird” is if I cheated and ignored the obvious.

This year I decided to change the challenge to Best Bird of the First Day. My 2020 winner is the turkey vulture that used to be absent on January 1.

Turkey vultures (Cathartes aura) are South American birds who’ve expanded their range into North America, year-round residents in the southern U.S. but only summer visitors up north.

Vultures migrate because they can’t eat our winter food supply. Though carrion is available year-round their beaks aren’t strong enough to rip open frozen food.

However climate change is doing them a favor. Last month in Pittsburgh most days were barely below freezing and five recent days were as much as 20 degrees above normal. Nothing was frozen.

Turkey vultures used to leave Pittsburgh for the winter but in this century a few began to linger here. The most reliable group roosted within sight of Dashields Dam on the Ohio River. Last month additional vultures were reported during the Pittsburgh Christmas Bird Count. Even so, I was surprised to see two of them soaring over McKnight Road on the first day of the year.

As more turkey vultures become year-round residents of Pittsburgh we can sing “Here to stay is the new bird” for yet another species.

(photo and map from Wikimedia Commons; click on the captions to see the original)

Eagles vs Drones? Golden Eagles Win

Golden eagle captures a drone in midair in France (screenshot from AFP video)

In 2015, when drones flew over sensitive urban spaces in France, the government passed new laws to restrict the airspace. However some places are so sensitive that rogue drones must be removed if they attempt a flyover. How can they be downed in mid-air without hurting anyone? The French military came up with an effective solution.

In 2016 France’s Army Air Force began a falconry program with four golden eagle chicks, named for the four Musketeers. Golden eagles are the only bird large enough to safely bring down a 4.5 to 9 pound drone (2-4 kilograms). The eagles were trained to view drones as prey and learned to catch them in mid air.

The eagles did so well that the Air Force made plans to add four more eagles the following year.

Click here or on the screenshots to watch a 2017 video of the eagles in training.

Golden eagle on glove in France (screenshot from AFP video)

Gold eagles versus drones? The eagles win!

(screenshots from AFP News video on YouTube; click here to watch the video)

Eagle-Sized Roaming Charges

Steppe eagle (photo from Wikimedia Commons)

In case you missed it …

Steppe eagles (Aquila nipalensis), pictured above, breed on the steppes of Eurasia and spend the winter in Africa, the Middle East, Pakistan, India or Southeast Asia, passing through Central Asia on their way south.

Range of steppe eagle (map from Wikimedia Commons)

Steppe eagles are endangered in Russia and Central Asia, threatened by persecution and power lines which they encounter on migration so the Russian Raptor Research and Conservation Network has fitted 13 of them with cell-enabled backpacks to track their paths. They plan to mitigate the most dangerous locations frequented by eagles.

The tracking backpacks send four text messages a day with date, time and the eagles’ GPS coordinates. If the bird is far from the cell network, the tracker stores the data until the eagle gets near a tower.

Steppe eagle in flight (photo from Wikimedia Commons)

This method worked well in 2018 because most of the eagles traveled near the Russian cell network. This year, however, an eagle named Min spent the summer far from the network in a remote part of Kazakhstan. Her backpack stored months of data that it couldn’t transmit until she flew near a cell tower in Iran (map below).

Approximate route of Min in Fall 2019, inexpertly drawn by Kate St. John on a map from Pinterest

In October the researchers were stunned to receive a cellphone invoice with eagle-sized roaming charges. They’d budgeted 15 roubles/message but roaming in Iran is 49 roubles/message. In just one texting session Min used up the entire year’s budget for all the eagles!

What to do? They set up a crowd-funding appeal that raised more than enough to cover this year’s charges (100,000 roubles) and Russia’s Megafon network offered to cover the cost, too. So the project is saved.

Learn more about the steppe eagles’ migration and roaming charges here on the BBC. Follow the steppe eagles’ saga at the Russian Raptor Research and Conservation Network.

Click on the map below to see where the eagles have migrated in the past two years.

p.s. What is 100,000 worth in U.S. dollars? About $1,560.

(photos and range map from Wikimedia Commons, Min’s hand-drawn route on map from Pinterest, steppe eagles’ migration map from Russian Raptor Research and Conservation Network. Click on the captions to see the originals)

NOTES: Steppes are prairies or scrubland similar to the Great Plains and Great Basin of North America. Steppe eagles face an additional threat: Because they eat carrion they are dying of diclofenac, just as vultures are.

Vigilant Against Red-Tails

Morela scans the sky, 8 Nov 2019, 1:09pm (photo from the National Aviary falconcam at Univ of Pittsburgh)

November is a busy time for raptors on the University of Pittsburgh campus. Migrating red-tailed and Cooper’s hawks pass overhead while the Cathedral of Learning peregrine pair, Terzo and Morela, watch the skies and defend their territory.

Morela is especially vigilant against red-tailed hawks. Months before we knew she was on campus, @PittPeregrines noticed a peregrine kept chasing red-tailed hawks away from the Cathedral of Learning.

  • Aug 26, 2:40pm — Red-tailed hawk hovering over the 20th Century club is chased north and hit repeatedly by a Pitt peregrine.
  • Sep 13, dusk — A peregrine leaps off the Oaklander Hotel and chases a red-tailed hawk, grounding it on the lawn at William Pitt Union.

Hope and Terzo didn’t bother with red-tails so something had changed. It was Morela.

Was she involved in this incident? On Friday Nov 8, Pitt Police and a PA Game Commission Game Warden rescued an injured red-tailed hawk from the patio at Tower B. (The tweet says “falcon” but don’t worry, it’s a hawk. No news on its injury.)

In their photo tweet you can see the Barco Law Building in the background. Kim Getz works there and has been keeping track of the red-tailed hawks that hang out at the Law School. She hopes the injured bird wasn’t this adult that keeps the rodent population under control …

Adult red-tailed hawk dining at the Barco Building (photo by Kim Getz)

… or this curious youngster.

Immature red-tailed hawk at the Barco Building (photo by Kim Getz)

By 3pm Saturday afternoon, 9 November 2019, I was sure that at least one adult red-tailed hawk was doing just fine. I watched it glide low just below tree height on its way to Frick Fine Arts while Terzo and Morela performed a courtship flight at the Cathedral of Learning.

At 4:12pm Morela made a round of her territory from Schenley Plaza to Heinz Chapel and the Cathedral of Learning.

All is calm. Morela rules.

(photos from the National Aviary falconcam at Univ of Pittsburgh, @PittPolice and Kim Getz)

The Whining Is Over

By the end of September the whining is over. Juvenile raptors, like this young red-tailed hawk, have left home to start life on their own. Now they hunt in silence. Loud begging scares their prey.

I miss the begging sounds of summer because they helped me find songbirds. The whining juvenile red-tailed hawk in the linked video below has attracted songbird attention.

Juvenile red-tailed hawk calling (click for the video by JustBirds)

How many songbirds can you identify in the background? (Hint: he was filmed in Michigan.)

(video from Cornell Lab Bird Cams, screenshot from JustBirds)

From Grief To Action

Red-winged blackbird, Point Pelee, Ontario, 2010 (photo from Wikimedia Commons)

Yesterday I shared a report on the stunning loss of North American birds. 29% have disappeared since 1970 with heavy losses in many of my favorite species including blackbirds, warblers and wood thrushes. We grieve as Silent Spring happens before our eyes.

Though the report was depressing there were two bright spots that provide hope and can guide us from grief to action. The report includes this happy news: Ducks increased 56% and raptors 200% thanks to our intervention.

Ring-necked ducks take off, March 2011 (photo by Steve Gosser)
Ring-necked ducks, March 2011 (photo by Steve Gosser)

Ducks were in such steep decline in the early 1900s that hunters banded together to reverse the trend. The main cause of decline was habitat loss — the disappearance of wetlands — so they worked to pass wetland protection laws in the U.S. and Canada and migratory duck protection in Mexico. People gave of their time and money to build wetland habitat for waterfowl, especially through Ducks Unlimited. Their effort paid off.

Female peregrine in flight, May 2016 (photo by Peter Bell)

Meanwhile, by 1970 peregrine falcons were extinct east of the Mississippi and bald eagle populations had crashed. The cause was a pesticide — DDT — that was outlawed in the U.S. in 1972. With Endangered Species Act protection and the work of recovery programs, peregrine falcons and bald eagles made a stunning come back.

The recent decline in North American birds has its root in the same problems we solved for ducks and raptors: habitat loss and pesticides. We solved it before, can do it again. We can turn our grief into action.

Our actions can be small scale or large — from our own backyards, to local schools and parks, to the national level.

On a personal scale, Cornell Lab of Ornithology suggests seven simple things. As part of their list, here are two questions to think about: Do you treat your lawn? Do you ‘fog’ your backyard to keep mosquitoes away? Reducing insects means birds and nestlings starve.

On a local and national scale we can work to restore habitat and reduce pesticides through conservation organizations and our local Audubon and birding clubs (see list at end).

And finally, we can work to change attitudes toward nature and we can vote. Wetland protection and pesticide laws were key to saving ducks and raptors. Every level of government — from school board to nation — makes decisions that affect birds.

After an interval of grief, we’ll have a lot to do. We can do it. We just have to try.

Red-winged blackbird flock, Kansas, 2006 (photo from Wikimedia Commons)

(red-winged blackbird photos from Wikimedia Commons; 7 Simple Things from Cornell Lab of Ornithology; click on the captions to see the originals. Ring-necked ducks by Steve Gosser, peregrine falcon by Peter Bell)

p.s. Pittsburghers, here are some land and bird conservation organizations, mostly local:

Bald Eagle Or Golden?

Juvenile bald eagle near the Harmar Twp nest, 1 July 2018 (photo by Annette Devinney)
First year juvenile bald eagle near the Harmar Twp nest, July 2018 (photo by Annette Devinney)

Young bald eagles can be hard to identify because they don’t have white heads and tails. To complicate matters, our field guides show a very similar bird, the golden eagle. How can you tell if a large dark bird in western Pennsylvania is a bald eagle? Here are some tips, plus a comparison to golden eagles.

First, make sure the bird is not a turkey vulture. See V Is For Vulture for details.

Second, the location, time of year, and habitat are your best clues to its identity.

  • Location and time of year:
    • Bald eagles are year round residents of Pennsylvania. Their population is booming.
    • Golden eagles are rare in eastern North America and only seen at Pennsylvania hawk watches during fall and spring migration.
  • Habitat:
    • Bald eagles eat fish and are found at rivers and lakes. They are tolerant of human settlements and will nest in suburbs or towns near water.
    • Golden eagles eat meat and are found in open country such as mountains, cliffs, tundra, grassland and deserts. They avoid human settlements.

Third, you’re ready to look at plumage with this caveat: I am not an expert at aging immature bald eagles. If you have tips, photos or corrections please leave a comment.

BALD EAGLE FIRST YEAR PLUMAGE: (“first year” and “juvenile” are synonymous)

In their first year of life juvenile bald eagles have dark gray beaks, dark brown feathers overall with variable white mottling under their wings and tails. The photo at top by Annette Devinney shows the white mottling seen in flight.

Hays juvenile bald eagles before they fledged, June 2014 (photo from that Hays Bald Eaglecam)
Hays juvenile bald eagle, H8, June 2018 (photo by Annette Devinney)
Harmar’s juvenile bald eagles playing in the sky, July 2018 (photo by Annette Devinney)

SECOND AND THIRD YEAR PLUMAGE: (called “immature” birds)

In their second year bald eagles turn whiter with additional mottling on their backs, bellies and wings. Still mottled in their third year, their bodies darken while their heads and tails turn whiter.

Second year birds may show uneven trailing edges on their wings because first-year flight feathers are longer than those of older birds. This bird shows a mix of old and new feathers.

Immature bald eagle, second year (photo by Steve Gosser)
Immature bald eagle (photo by Steve Gosser)

FOURTH YEAR PLUMAGE: (nearly “adult,” may nest at four years old)

Bald eagles complete their adult plumage in their fourth year. Their heads and tails have a slightly dirty appearance due to a few dark feathers. In 2013 the new Harmar female had some dark tail feathers, below. She was probably only four years old.

Harmar bald eagle, 2013 (photo by Steve Gosser)

FULL ADULT PLUMAGE: (fifth year and beyond)

Adult bald eagles with white heads and tails cannot be mistaken for any other North American bird. In the photo below, the Hays female carries a fish to her young.

Mother bald eagle carries a fish, apparently to entice H7 (photo by Annette Devinney)
Mother bald eagle carries a fish to H7 at Hays, 2017 (photo by Annette Devinney)

COMPARING GOLDEN AND BALD EAGLES:

Juvenile bald eagles resemble golden eagles in size and coloration. However …

Golden eagles are dark brown with golden feathers on the nape of the neck. Adults have completely dark underwings and tails. Immatures have a white band at the base of the tail and dark underwings, not mottled, with either a white line down the middle of the wing or a white half moon at the wrist (see below). Golden eagles’ heads look smaller than bald eagles’ because their beaks are smaller. Here are two photos of golden eagles in flight at the Allegheny Front by Steve Gosser.

Golden eagles at the Allegheny Front (photos by Steve Gosser)

Finally, golden eagles are extremely rare in Allegheny County, even as flyovers, while bald eagles are resident year round if the rivers don’t freeze. An all-dark eagle near Pittsburgh is most likely a juvenile bald eagle. It may have been born here.

Learn more about aging bald eagles and comparing them to goldens at these links:

(photos by Annette Devinney, Steve Gosser and the Hays Bald Eaglecam)

White Barn Owls Stun In Moonlight

Barn owl, Scotland (photo from Wikimedia Commons)

Most owl species have camouflage-colored bellies, but most barn owls (Tyto alba) do not. Though their backs blend into their surroundings, the majority have brilliant white faces, bellies, underwings and legs. The rest are better camouflaged in rusty red, below.

Barn owl with reddish belly (photo from Wikimedia Commons)

The white color stands out in moonlight but is this visibility a disadvantage? Does the white owl’s prey see it coming and escape? Are reddish owls more successful on moonlit nights? Researchers ran tests to find out.

Barn owl watching for prey (photo from Wikimedia Commons)

In a barn owl study in Switzerland, scientists have been tracking plumage, prey availability, moon phases and breeding success for over 20 years. When they correlated moon phase with hunting success, they found that reddish barn owls have lower success on full moon nights than white ones.

This seemed very odd so they set up an experiment with full moon lighting and two taxidermied owls posed in flight — one white, one reddish. When a vole was placed in the “moonlit” room and presented with a flying (stuffed) owl, it froze in place for an extra 5 seconds when it saw the white one. Those 5 seconds were just enough time for the white owl to pounce. The reddish owl was out of luck. Apparently the glowing white plumage has its advantages.

White barn owls are stunning in moonlight.

Barn owl in flight, glowing white (photo from Wikimedia Commons)

Read more at “Moonlight Helps White Barn Owls Stun Their Prey” in Smithsonian Magazine.

(photos from Wikimedia Commons; click on the captions to see the originals)