6 December 2024

Since late October visiting crows have been pouring into town to join Pittsburgh’s enormous winter crow flock. Their numbers in Shadyside and Oakland grew from 3,600 in mid-October to over 8,000 in mid-November … and then I lost track of them because they moved the roost and changed their flight path.

Alas! The flock is still growing — perhaps to 20,000! — and just three weeks from now on Sat. 28 December will be the annual Pittsburgh Christmas Bird Count (CBC) when we’ll confirm the number of crows that come to town for the winter. If we can find them.

I had hopes last Saturday 30 November when Betty Rowland saw a huge flock staging at Schenley Park’s golf course, photo above. But when Betty checked again on Monday the crows were completely gone.

Our winter crows change or split their roost often in late December because they wear out their welcome so quickly. (See examples here.) So where are they now?

Please help. Let me know where you see lots of crows after sunset or at night in the city and/or Allegheny County. Tell me about …

• Huge flocks of crows
• After 4:00pm
• Where are they?
• If flying, what direction are they going?

Your sightings are especially important in the week before the CBC, December 22-27.

To get you in the mood, here’s a video from Winter Crow Roost in Lawrence, Massachusetts where they’ve ramped up crow counting with photography and videos. Woo hoo!

For more about counting crows in Lawrence, MA see their website at Winter Crow Roost.

20 November 2024

The number of crows in the East End increased recently after they began roosting at Pitt again. On Saturday night I saw hundreds of crows in the trees at Carnegie Library and the Cathedral of Learning so on Monday afternoon I did a walk-about to count “crow trees” that showed evidence of roosting. (A big tree holds 250 crows.)

My tree count was way too high so on my way home I paused at Fifth and Craig to count the huge flock passing overhead on their way to Pitt. 8,000 to 8,500 crows.

On Tuesday evening I could see crows staging in the trees above Morewood Ave so I counted again. 8,000 crows. … And this is just the East End flock.

The crows may be wondering why I’m counting(*), but crows can count too though not so high. A study of carrion crows (Corvus corone), published in Science last May, showed that this Eurasian equivalent of the American crow can count up to 4 out loud, similar to human toddlers.

Three carrion crows were trained to vocalize with one, two, three, or four caws depending on the number they saw in front of them. They were also taught to tap the screen when they were done counting.

The birds boasted a 100 percent accuracy rate at counting to one, a roughly 60 percent success rate at counting to two and about a 50 percent accuracy rate for three.

Crows particularly “disliked” the number four (40 percent accuracy), sometimes refusing to caw at all when prompted and pecking at the screen to end the trial immediately, [according to] study co-author Diana Liao, an animal physiologist at the University of Tübingen.

Additionally, the crows paused before cawing correctly, showing longer reaction times before producing higher totals of vocalizations.  This delay is consistent with mental planning.

— SMithsonian Magazine: Crows Can ‘Count’ Up to Four Like Human Toddlers, Study Suggests

The test reminds me of a story Chuck Tague told me many years ago. He and his wife Joan visited a bird blind to see an elusive bird that would not come out if a crow was watching. Unfortunately whenever he and Joan went to the blind a crow would follow them and wait for them to leave.

They decided to fool the crow. Both of them went into the blind but only Chuck came out. Surely the crow would leave and Joan would see that elusive bird. Nope. The crow counted two people going in and only one came out. They changed it up and Joan came out but it made no difference. The crow could certainly count two people.

Maybe I’ll have a chance to try this some day. Meanwhile, read more about the study in Audubon Magazine: Crows Can Count Aloud Much Like Toddlers, New Study Finds.

(*) p.s. I’m counting crows to get in practice for the Pittsburgh Christmas Bird Count on 28 December 2024, the Saturday after Christmas. Last year we counted 15,000!

4 November 2024

Pittsburgh’s winter crow flock is building as more birds from the north join the thousands already here. By the end of December at the Pittsburgh Christmas Bird Count, there will be as many as 20,000 crows on the move at sunset.

This month while the flock is growing, the roosts that were adequate in October are too small, so they move the entire roost or split into several locations. The moving or splitting happens every week, if not more often.

On Halloween they chose a favorite spot in the Hill District overlooking the Allegheny River, but those coming from the southeast had to change course to get to it. Thousands flew over my apartment building just after sunset on 1 November. On 2 November they found a shortcut and took a different route.

Tonight sunset is during rush hour at 5:12pm and for the first time this fall many people will be outdoors while the crows are on the move. Those who hadn’t noticed the flock before will think the crows suddenly showed up. Nope. Crows have been traveling at sunset all their lives. It’s the people who suddenly showed up.

p.s. Thank you to Sue Faust & Betty Rowland for alerting me to the crows’ whereabouts. It’s always a challenge to find the roost, especially in late December.