It used to be easy to identify crows in Pittsburgh. Every crow was an American crow (Corvus brachyrhyncos). But not any more.
In recent years fish crows (Corvus ossifragus) have been expanding their range northward from the coastal Southeast. The first I’d heard of them in western Pennsylvania was when Marcy Cunkelman said they were common in Indiana, PA. I found this odd because Indiana is land-locked.
What was a fish crow doing without fish? They earned their name by scavenging on beaches but fish crows aren’t picky. They’ll eat anything. They must have made an easy transition from dead fish to discarded hamburgers. Perhaps one spring they followed some American crows to western Pennsylvania — and so they are here. This year, they’ve been reported nesting in the City of Pittsburgh.
Fish crows are smaller than American crows but they’re impossible to tell apart except by voice. As Birds of North America Online says, “The only reliable difference between the two is vocal. The Fish Crow sounds like an American Crow with a bad cold.”
I’m sure you can imagine an American crow’s call without listening but here’s a recording to prepare you for the difference. “Caw, Caw, Caw.”
Easy? Yes, except at this time of year. Baby American crows have nasal voices too (yikes!) so the call you hear could be a baby crow. There’s still a difference, though. Baby American crows call with a single note. (Click hear to hear.)
So, now that we have two kinds of crows, you’ll have to wait until they speak to be sure of them. “Uh oh!”
Three readers alerted me to this video that’s sweeping the Internet.
In Russia, a hooded crow repeatedly surfs down a snowy roof, riding something that looks like a Frisbee. When the video begins, there’s already a surf-track on the roof, evidence that he’s been doing this for a while.
Though they’ve moved away from residential neighborhoods and are keeping a relatively low profile, Pittsburgh’s East End crow roost has attracted some attention lately.
Perhaps it’s because sunset is later so we see them during rush hour(*). Perhaps it’s because they’re noisy. Perhaps it’s their sheer numbers.
Jack and Sue Solomon counted them on December 31 for Pittsburgh’s Christmas Bird Count. Knowing the crows gathered above Bigelow Boulevard, Jack and Sue waited at dusk in a parking lot opposite Liberty Ave. and 25th Street and watched the hillside above The Strip. Their estimate? More than 12,000 crows.
What does that look like?
Sharon Leadbitter filmed them at twilight last Friday. The first video (23 seconds) shows them flying overhead at Polish Hill. The video below (2:18) shows them filling the trees above Bigelow Boulevard near the French Fry sculpture.
The flock is raucous only at their staging area. After dark they fall silent and leave the trees to roost in parts unknown.
If you want to witness this for yourself, January is the time to do it. Next month the flock will begin to break up. By March they’ll be gone.
In Pittsburgh they really don’t want us to know. They’re loud and obvious at their pre-roost staging areas but that’s not where they’ll sleep. After the sky is dark they leave the staging area and fly silently to the roost. Black birds in a black sky.
Wednesday evening Karen Lang noticed them near the University of Pittsburgh’s Alumni Hall around 6:00pm. Though it was dark she could see their profiles against the city-lit sky and estimated 1,000 crows were on Soldiers and Sailors Memorial Hall roof and the nearby trees.
Peter Bell saw them, too, so he brought his camera Thursday evening. From his vantage point on the 12th floor of Chevron Science Center, the roof looked like this while the crows were still arriving.
There were also on the trees.
And perfectly lined up on the roof, a couple of crows per tile.
Last night I went to see for myself. Their dark profiles were visible from Fifth at Bigelow but when I moved up Bigelow for the same view as Peter’s pictures, the streetlights’ glare made the crows hard to see.
That’s how the crows like it. When things get too hot for them, they move their roost.
Some night we’ll discover that Soldiers and Sailors roof is missing its black ornaments.
Following their pattern of prior years they’ve begun their winter roost in Oakland and will slowly adjust its location until by December they’ll gather west of Polish Hill and roost in the Strip.
Or maybe not. It remains to be seen.
Right now they fly over Peter Bell’s apartment every night. On Sunday he shot this video of them flying southwest and pausing on the trees nearby.
Peter wrote on YouTube, “Every fall thousands of crows gather in Pittsburgh. I was lucky enough to be in a spot they all decided to pass over as they decided on a place to roost for the evening. On this night, it took about 40 minutes from the first few I noticed until most had passed by. This night they weren’t being too noisy, so most of the recorded audio was buses and other traffic, so I swapped it out. Music: Schubert’s Serenade (Lied from Schwanengesang D.957) recorded by Anne Gastinel”
Inevitably a flock this large makes us wonder: How many crows are there? How do you even estimate their number? Here’s how.
Note the starting time. (For example: 5:45pm)
Pick a reference point in the scenery.
Use a timer and count the number of crows passing the reference point for 1 minute or 3 minutes, whichever is most useful. Make several of these timed counts so you can get a decent average of crows per minute.
Now relax and watch the crows passing by. If their concentration increases or decreases noticeably, redo the timed counts.
When the crows taper or stop coming, note the ending time. (For example: 6:30pm)
For how many minutes did the crows pass the reference point?
Use some easy algebra: minutes * crows/minute = crows.
You can try this while watching Peter’s video. Count the number of crows exiting the frame, then multiply by 40 minutes.
p.s. Dedicated crow watchers (like me) have been noticing the crows for a couple of weeks. I predict that everyone else will notice them for the first time on November 7. Why? Because we’ll change the clocks (“fall back”) on November 6 and suddenly, on Monday November 7, the crows’ rush hour will coincide with ours.
The trail follows Little Beaver Creek as it cuts through the surrounding hills. Along the way there are remnants of the channel and locks of the Sandy and Beaver Canal that ran for 73 miles through 90 locks and two tunnels from Bolivar, Ohio to the Ohio River at Glasgow, Pennsylvania.
Completed in 1848, 20 years after it was chartered, the canal operated for only four years. It closed in 1852 after the Cold Run Reservoir Dam broke and ruined much of the canal. By then competition from the Cleveland and Pittsburgh Railroad made it uneconomical to rebuild. The canal boom ended abruptly.
At Grey’s Lock I stopped to read the historic marker but I didn’t absorb what it said because my attention was snagged by the sound of crows. Just out of sight, they were flying my way. 150 passed overhead and congregated somewhere on the north side of the creek, still within earshot.
That flock is just the start of something big.
Right now the crows are gathering in the countryside. 150 here, 200 there. Some have made it to town, but no great numbers yet.
Soon, very soon, the crows will come to Pittsburgh. By winter we could have 10,000!
Fall is coming, school’s in session and in about eight weeks the crows will be back in town.
For now they’re in no rush to get to Pittsburgh. I don’t expect large numbers until October, but when they come will I see a difference in them? Did they learn new tricks this summer? Will they be even smarter than last year?
Perhaps they’ve learned to use tools!
Here’s a year-old video from Science Friday that shows just how smart crows can be. (Click on the image to get to the video website from September 2010.) The birds in the film are New Caledonian crows who live on a Pacific island and are famous for using tools.
Steve Valasek sent me this photo of a raven landing and said, “We visited Acoma Pueblo on Monday and saw many ravens riding the updrafts on the sides of the mesa. Our guide said that he’s actually seen them fly upside down.”
You bet they fly upside down!
Ravens are very acrobatic fliers. I’ve seen them tumble together many times as they launch over the cliffs at Acadia National Park in Maine. They seem to get a lot of joy from doing this and might even be competing to see who can make the best moves.
It’s so hard to describe how cool they are that I found a video of ravens sky-tumbling at Lundy Island, Great Britain. Watch carefully at 29, 40 and 44 seconds and you’ll see one of them completely flip over sideways. Awesome!
Ravens are cool, but for speed you can’t beat a peregrine. While searching for the first video, I found this one of a peregrine harrassing two ravens at Culver Cliff, Isle of Wight. The big soaring birds are ravens. The very fast, smaller, flapping bird that appears from above at 3 seconds and 13 seconds is the peregrine.