27 June 2025
Ravens are omnivores whose varied diet includes roadkill, rodents, grasshoppers and the nestlings of smaller birds. Since ravens are the largest “songbird” all the smaller birds mob ravens. Ravens in turn mob hawks.
Watch how adult ravens keep the world safe for their youngsters in this video by Vance Crofoot.
p.s. Ravens also attack bald eagles. This photo is from Orcas Island, Washington. I’ve seen the same thing at Hays Woods.
20 May 2025
What is the easiest way to find an owl? Listen for angry birds.
Songbirds always view owls as dangerous but during the nesting season they loudly mob owls to drive them away from their nests and fledglings. This attracts more birds to join the chase. What a ruckus! Here are some examples.
In this video blue jays mob a mother screech-owl who is taking a break near her nestbox in Florida. She isn’t going to leave the area so the mobbing isn’t going to work. Notice her reaction!
Her behavior is notable because:
Screech Owl uses newly documented scary daytime defensive posture against annoying Blue Jays and Mockingbirds consist of wide eyed blinking and open mouth snapping to look more intimidating.
— video description from MyBackyardBirding on YouTube
American crows bravely mob a great horned owlet, making it very easy to find this branching youngster.
Crows chase an adult great horned owl when it’s near their nest or fledglings. But there is real danger in this activity! The owl will eat the crow if he can catch him. There are moments in this video when the crow takes a big chance. (Watch for the cameo appearance of a mockingbird.)
RARE BIRDS! I could not resist starting this blog with a rare songbird chasing a rare owl. Both birds in the top photo — a Brewer’s blackbird and an American barn owl — are extremely rare in southwestern Pennsylvania. If I saw a barn owl being chased by a Brewer’s blackbird in the Pittsburgh area, no one would believe me. Both birds occur regularly in San Luis Obispo County, California where the photo was taken.
(photo embedded from Kristie Clarke-Rozsa on Flickr; click on the photo to see the original)
8 May 2025
Ravens (Corvus corax) are becoming more common in Pittsburgh so that I see them now about once a week. Never a flock, just one or two ravens at a time.
If Pittsburgh had a lot more raven pairs or even flocks of “teenage” ravens, we’d get to see them playing in the sky. Photographer Kristie Clarke-Rozsa captured a raven game in Chilliwack, BC, Canada, described below.
Two ravens tumbling down to the ground playing pass the stick, whoever lasts the longest before chickening out wins!
— description of photo at top by Kristie Clarke-Rozsa on Flickr
To see raven games in motion, visit this 2018 vintage article with my all-time favorite raven video.
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14 March 2025
I’ve seen a lot of ravens in the past two weeks — 11 in Minnesota, two as we landed at Pittsburgh airport, and one over Aspinwall on Tuesday. When I found Vance Crofoot’s 3-minute video explaining raven territories I was fascinated.
Here’s what we learned:
The first comment on the video points out how different ravens are from crows!
Very informative! It’s interesting that the intergenerational behaviour is different from crows whose juveniles hang around longer and actively assist their parents in raising the next chicks and fledglings. The ravens’ cooperative behaviours are very well adapted to their needs and types of threats.
— Comment on the video from @julieprior3126
And why are there so many ravens in this video? Southern California has a lot more ravens than we do in the East, as shown on this eBird map.
1 March 2025
Yesterday’s news was sobering for Pittsburgh’s winter crow flock when the Post-Gazette reported that 50 crows found dead in January tested positive for H5N1 highly pathogenic avian influenza. It was the first incidence of avian flu in Allegheny County in more than two years.
The Pittsburgh crows were collected on Jan. 24 and tested positive in preliminary tests for the deadly virus on Feb. 10, said Travis Lau, communications director for the Game Commission.
— Post-Gazette: First Pittsburgh cases of avian flu in years detected in American crows
It’s not hard to imagine how it happened. In January Pittsburgh’s winter flock of 15,000 crows roosts communally and fans out during the day as much as 50 miles to find food. The furthest travelers would have caught bird flu in an infected surrounding county and brought it to the roost. H5N1 is so contagious that it quickly spread to flock mates.
Apparently the crows knew what to do when death visited the roost. Crow watchers noticed that they changed the roost location a lot in January, perhaps avoiding sick birds and death locations. Maybe that’s why we haven’t heard of more crows deaths. Or maybe it simply takes weeks for the reports to reach us.
Meanwhile keep in mind that if you find a sick or dead bird you should not touch it!
Because of the highly contagious nature of the virus among birds, and the fact that, while rare, it can be transmitted to humans, the Allegheny County Health Department (ACHD), the Game Commission and other agencies urge the public not to touch sick or dead birds and report them to the Game Commission.
Anyone who sees a sick or dead wild bird should report it to the PA Game Commission at 833-742-9453.
Residents who suspect their poultry is infected with avian influenza should call the Pennsylvania Bureau of Animal Health and Diagnostic Services at 717-772-2852, option 1.
Residents who feel ill after contact with sick or dead birds should consult their primary care physician or the Pennsylvania Department of Health at 877-724-3258.
— Post-Gazette: First Pittsburgh cases of avian flu in years detected in American crows
Read more in the Post-Gazette: First Pittsburgh cases of avian flu in years detected in American crows.
See the 2021-2025 distribution of highly pathogenic (HPAI, H5N1) avian influenza in wild birds in the U.S. by county as of mid-February 2025 here at USDA.
20 February 2025
Ravens have moral standards, they understand fair play, and when someone breaks their trust they refuse to deal with them again. Ravens hate a cheater.
We know this because researchers conducted a trading experiment in 2017 in which they built trust with ravens (Corvus corax). When a raven offered bread, the human gave him his favorite food, cheese.
Then one of the researchers accepted the bread but ate the cheese she was supposed to give to the raven, in effect saying, “Hah Hah Hah! Fooled you!”
The ravens were outraged! Find out what happened next in this vintage article.
p.s. Are we humans as smart as ravens when it comes to trust? Alas, some are not and the cheaters become bold.
4 February 2025
Bald eagles are top predators who will eat crow nestlings, fledglings and unwary adults if the opportunity arises, so crows learn from a very young age to watch out for eagles.
Even in the nest young crows hear and see their parents drive off hawks and eagles. In their first year of life, which they spend with their parents, they learn the rules of harassment.
Ten years ago photographer Phoo Chan went to the shore at Seabeck, Washington to photograph the bald eagles who arrive in large number during the midshipman fish run (Porichthys sp). He was very lucky to capture photos of a lone crow riding on an eagle’s back. See more in his article below.
Crows keep the world safe for crows. 😉
18 January 2025
Crow news has been coming fast and furious in Pittsburgh this week.
On Wednesday I posted an update (Crow Update, mid-January) even though I didn’t know where they were roosting.
On Thursday many of you responded with your own sightings including this video from Lyndsay Krut on Mt. Washington.
Then Friday morning the crows became famous when Pittsburgh photographer Dave DiCello happened to run through their morning staging area and posted his video on Facebook and Twitter. Dave DiCello Photography has 160,000 followers on Facebook. His post went viral.
That was Friday morning.
Friday evening Crow Patrol member Carol Steytler followed crows to the roost and found out they are drawn to Science! — specifically to the roof of the Carnegie Science Center and nearby trees.
Notice them on the roof edge in Carol’s photo.
Watch Dave DiCello’s morning video again and you’ll see them silhouetted against the base of the glowing eMotion Cone. Dave also took a daylight photo.
So now we know the crow map looks like this. Pink is morning, orange is evening, and that circle of pink and orange is the roost.
Thank you, everyone, for your sightings.
I’ll be interested to see what the crows do this coming week as Pittsburgh experiences extreme cold with temperatures down to -9°F and wind chills as low as -25°F. And they have to sleep outside. Brrrr!
15 January 2025
After the big push to find Pittsburgh’s winter crow flock for the Christmas Bird Count in late December I took a break and merely enjoyed them. Searching and counting is hard work so I didn’t look for crows and if I saw them I certainly didn’t count them. Thankfully, you’ve been letting me know what you see.
Fred’s comment yesterday makes me wonder if crows are roosting on Downtown buildings.
Last Friday, 1/10/25, just before 7 am there were thousands of crows flying around and roosted in trees of the little park on First Ave downtown (across from PNC) and perched on all the buildings around. Their collective cawing would have made conversation at normal levels difficult. Having seen similar numbers in Oakland and Schenley in the early evening, made me wonder if they make the pre dawn rally to town.
— Comment from Fred, 14 Jan 2025
Frances and Sue indicate crows might be tucked in across the river at Southside.
In recent days I have noted them flying west to east over Southside Flats early in the morning (dawn).
— Comment from Frances, 13 Jan 2025
Lots of crows roosting on E Sycamore St in Mt. Washington, starting about 30 minutes ago (4:30pm).
— Comment from Sue Thompson on 8 Jan 2025
In the past two weeks I’ve noticed crows flying east to west toward Schenley Park and the Hill District and staging briefly in Schenley before dusk.
So I put these 5 observations on a map. Orange is dusk, pink is dawn, the dots are staging areas.
Pittsburgh’s crows may have split or moved their roost this month and I wouldn’t be surprised if they did. Bitter cold temperatures like last night’s 7°F prompt crows to spend the night on a warm rooftops rather than in bare trees.
UPDATE: check the comments for additional news on 15 Jan.
And here’s a treat for crow watchers: In Lawrence, Massachusetts the Crow Patrol sees crows after dark on roofs and trees using infrared cameras. Notice how crows’ eyes glow white in infrared light. 🙂
29 December 2024
We tried but it was daunting. Last evening Carol Steytler, Claire Staples, Lisa Kaufman and I counted crows coming into the roost near the VA Hospital in Oakland for the Pittsburgh Christmas Bird Count. 15,000 crows. More or less. Probably more.
For an accurate count we needed all these conditions to be met simultaneously and all of them are under the crows’ control. Last night the crows beat us with blobs and darkness.
Darkness: Here’s what I mean. You can’t see the crow until I alter the photo (from Wikimedia Commons). Nor could we.
Details of the count:
The crows used the same roost site (sort of) that we found on Friday: the VA Hospital roof + nearby buildings. Miraculously they didn’t change the roost. However, the roof itself is too high to see so we used flight-path counting from the OC Lot parking deck. I’m sure some were hidden by buildings as they came in and weren’t counted.
Flight paths change day to day but Saturday’s was better than Friday’s from their pre-roost staging site in the west, backlit by the glow of sunset as shown at top. Very soon it was too dark to see black birds in a black sky. And the crows were frequently diverted by Stat MedEvac helicopters flying back and forth from UPMC Presbyterian.
Crow flock flight density — the blobs — changed all the time of course. We saw 100 crows in long strings, in very tight balls, and everything in between. Hard to count.
I’ve been counting crows for the CBC since 2018. It is always a challenge.
15,000 crows? We will never know for sure.
The crows are probably laughing at us.
p.s. Lisa and I are thinking of practicing the blob-count next month while the crows are still in town. If you have a suggestion for counting you must first count with us this winter. (I’m not kidding!)
If you’re an experienced crow counter no need to join us; we welcome your tips.
