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.
It’s not often that you see a raven’s nest in western Pennsylvania.
This spring Tim Vechter has been watching a family of ravens near Greensburg. He took their picture through his scope last week when the four young birds were just about to fledge. By now they’ve probably left the nest.
Saturday morning there was a mystery on my street.
Ten minutes before dawn a huge flock of crows flew over my neighborhood, then turned and wheeled over the ballfield, cawing loudly.
They were hard to see in the dark but they were easy to hear. They circled several times outside my window. It was so unusual that I reported them on PABIRDS.
At mid-morning I heard sirens. Six police cars, a firetruck and an ambulance roared up my street to the ballfield. The firemen carried their medical emergency kits to the bleachers, an area not visible from my side of the park. Soon they returned and drove away. The ambulance stayed longer but they left too without doing anything.
Meanwhile camera crews from all three TV news stations had set up their equipment across the ballfield and were pointing their cameras at the bleachers. A plain white car arrived in front of my house and three people emerged, pulling on purple latex gloves.
By now I had guessed that someone was dead. I couldn’t stand the suspense so I got my 10-power birding binoculars and walked around the ballfield to the vicinity of the TV crews.
With binoculars I could see that there was indeed a body on the cement bleachers. The police and detectives were taking pictures, checking the scene, examining, talking. The body was on its back, upside down, crumpled over itself as if it had fallen from the sky. It was in an unnatural position but its white face was up, easily seen from above in faint light.
So that’s why the crows wheeled and cawed.
The crows know. They saw it first. Now it’s up to the coroner and detectives to find out what happened.
p.s. Here and here are the news articles. The death was ruled a suicide.
If I was to place a bet on crows I’d wager they didn’t spend last night in the plane trees on University Place in Oakland. I’d win this bet because of what I found there less than 24 hours ago.
Yesterday morning I got a call from a Pitt employee who tracked me down out of concern for the peregrines. Marian had found a very large raptor standing on the ground near Soldiers and Sailors Hall on University Place. The bird would not fly away and there were feathers scattered on the ground beneath its feet. She was concerned that this was one of the peregrines and that it was injured and unable to fly away.
The situation sounded like a red-tailed hawk on a kill but you never know. I was happy to help and went over to check.
As I arrived at University Place I noticed a lot of crow poop on the sidewalk beneath the London plane trees. The closer I got to the site, the more poop there was.
When I reached the place Marian described I didn’t find a large bird on the ground but I could tell exactly where he’d been. Right next to the sidewalk was a big pile of crow feathers, a few crow bones and a crow’s skull and beak. Whoa! Someone had been eating crow!
I imagined the fear in the flock when that raptor arrived. I’m sure it scared the poop out of them and they left in a hurry. No wonder the sidewalk was gross.
Now there’s one less crow among the 10,000+ who roost in Pittsburgh and those still living can see how he died.
I can pretty much guarantee the crows won’t be back there soon.