Category Archives: Bird Behavior

What Are Crows Saying? Listen to the Gaps

Crow cawing (photo by Bennilover via Flickr Creative Commons license)

5 December 2024

Crows are so vocal that we can’t help but think their caws are a language. So what are crows saying in their big boisterous flocks before they roost?

Dr. Douglas Wacker at University of Washington Bothell (UWB) wondered the same thing so in 2017 his team began recording and analyzing pre-roost aggregations on the UWB roofs. The rooftop recordings were not enough to crack the code so now the team has turned to spectrogram analysis.

Dr. Wacker presented information on crow vocalizations at the Olympic Peninsula Audubon Society in November 2024. To measure the calls they analyzed these components.

  • Syllable = a single caw
  • Gap = the length of silence between caws
  • Call = a series of caws
  • Pause = the length of silence between calls
screenshot from Dr. Douglas Wacker presentation to Olympic Peninsula Audubon, Nov 2024

The team recorded crow vocalizations in various contexts and compared the spectrograms. And they discovered an unusual thing. Crows appear to be “saying” things in the silence between their caws (gaps) and the pauses between their calls.

  • Gaps between caws: Are longer in pre-roost aggregations (evening) than in post-roost aggregations (morning).
  • Pauses between calls: Are shorter while mobbing an owl than in pre-roost aggregations.

If you want to know what a crow is saying, listen to their silences.

Crow cawing (photo by Jennifer Aitkens via Flickr Creative Commons license)

Learn more about crow language in this Olympic Peninsula Audubon Society’s video. I have set it to start nearly an hour into the meeting, beginning with spectrogram analysis of crow calls. I’ve included this 15 minute portion here because it is so interesting. Click here to see the entire 1.5 hour meeting.

video embedded from Olympic Peninsula Audubon Society on YouTube. (Starts at 58 mins into the recording)

Some day we might know what this crow is saying. In the meantime, listen to the gaps.

Crow cawing (photo by Jason Hopkins via Flickr Creative Commons license)

p.s. Dr. Wacker described an intriguing idea: The messages in human language come from our sounds. The messages in crow language appear to come from silences. Perhaps we can’t figure out what crows are saying because we aren’t used to listening to the silences.

It’s Time to Find the Crows!

Crows staging at Schenley Park golf course at sunset on 30 Nov 2024, 4:57pm (photo by Betty Rowland)

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!

video embedded from Winter Crow Roost on YouTube

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

Meet Me At The Ledge

Ecco calls from the ledge, 26 Nov 2024 (photo from the National Aviary snapshot camera)

4 December 2024

In just 17 days the winter solstice on 21 December will bring us the shortest day and longest night. Since peregrines cue on the amount of daylight to trigger their breeding season, they aren’t in the mood for courtship right now. But the Pitt peregrines stay at the Cathedral of Learning year round and occasionally visit the nest ledge anyway in the off season. Sometimes they call for their mate to join them in a bowing session.

In the snapshot above Ecco calls for Carla to join him last week. “Hey, Carla. Come here!” She didn’t show up then, but she stopped by on Sunday. However Ecco didn’t arrive. (Note: The sun’s low angle made white dirt-spots glow on the camera housing.)

Carla at the Pitt peregrine nest, 1 Dec 2024 (photo from the National Aviary snapshot camera)

Finally on Monday Ecco and Carla met at the ledge (slideshow from the National Aviary snapshot camera).

Always Turn Right

Wild budgerigar flock in Western Australia (photo from Wikimedia Commons)

2 December 2024

How do birds avoid midair collisions? In 2016 scientists learned that budgerigars flying head on toward each other avoid crashes by always turning right.

Wild budgerigars bathing in Karratha, Australia (photo from Wikimedia Commons)

Researchers in Australia trained 14 male budgies to fly in a narrow well lit tunnel, one at a time. After the birds were acclimated they positioned one bird at each end of the tunnel and let them fly straight at each other. Two set of cameras recorded the birds’ reactions.

Over the course of four days, seven budgie pairs made 102 flights with no mishaps. When the researchers reviewed the video, they saw that the birds avoided any aerial mishaps thanks to two evolutionary traits. About 85 percent of the time, the birds turned right upon approach. “This seems to be a simple, efficient and effective strategy for avoiding head-on collisions,” Srinivasan said. 

The budgies also seemed to decide whether to fly over or under an approaching bird, and the pairs rarely made the same choice. … The researchers speculate that either each budgie prefers one flying height over the other, or flock hierarchy determines who flies high and who flies low.

Audubon Magazine: Birds Avoid Mid-Air Collisions By Following These Two Simple Rules

Here’s what the tests looked like.

video embedded from New Scientist on YouTube

We use the same principle in traffic. “Stay on the right.”

Traffic in Yellowstone National Park, July 2014 (photo from Wikimedia Commons)

Well, actually, 70% of the world drives on the right, 30% on the left. Heaven help you when you drive in a country that does the opposite of what you’ve learned!

Fortunately budgies always use the same rule.

Nuthatch Says: I’m Warning You!

White-breasted nuthatch threat display (photo from Wikimedia Commons)

1 December 2024

White-breasted nuthatches (Sitta carolinensis) are small but spunky. When they have a good spot at the feeder they defend it by puffing up.

Sometimes it’s just a mild warning like this tail-fanning to a house sparrow.

White-breasted nuthatch shows a mild warning to an incoming house sparrow (photo from Wikimedia Commons)

Sometimes it’s an open wing display like this one to a tufted titmouse.

White-breasted nuthatch tells tufted titmouse to go away (photo from Wikimedia Commons)

And if it’s really important the nuthatch opens its wings and sways side to side in a mesmerizing display. The bluebird on the other side of this feeder stares for a while and decides not to stick around.

White-breasted nuthatch tells bluebird to go away (video embedded from Birder in VA on YouTube)

I’ve never seen this swaying threat display but I learned about it in BirdNote’s podcast: Nuthatches Sweeping the Nest after they described another unusual nuthatch behavior.

Did you know that white-breasted nuthatches use crushed bugs and other items to lay scent outside the entrance to their nests? Listen to BirdNote to find out more …

… and then watch a nuthatch sweep a bug around its nest hole.

video embedded from Athena Gubbe on YouTube

Now that winter is really here, fill your feeders and wait to see a nuthatch tell the other birds, “I’m warning you!”

Turkey Owns the Road

Wild turkey crossing a road in Rhode Island (photo from Wikimedia Commons)

29 November 2024

Now that Thanksgiving is over turkeys can own the road again.

It’s been a long time since I’ve seen a wild turkey cross the road in the City of Pittsburgh. Six years ago they were very common in Pittsburgh’s East End but there are gone now, perhaps because the City’s huge deer population eats all their winter food.

If you want to see a lot of turkeys visit Pittsburgh’s northern suburbs. In February I saw 20 cross the road near North Park.

Fortunately none of them wanted to challenge cars!

video embedded from The Dodo on YouTube

Counting Crows? Crows Can Count

Is this crow counting something? (photo from Wikimedia Commons)

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.)

Crows gathering at dusk in Schenley Park, 21 Jan 2017 (photo by Mike Fialkovich)

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!

Budgie On the Cell Phone

Budgerigars (photo from Wikimedia Commons, created by merging two photos)

15 November 2024

Budgerigars or budgies, Melopsittacus undulatus) are native to Australia but are so popular as pets that they have been bred in captivity since the 1800s, resulting in colors such as blue not found in the wild.

Part of the budgies’ charm is that they love to mimic human speech. They do it because …

In the wild, flocks of parrots develop distinct local dialects. Research indicates they use these to distinguish familiar members of their flock from unfamiliar birds of other flocks. Birds respond more to vocalizations that are familiar to their own, and they ostracize individuals that vocalize in a different way. Birds raised in captivity might mimic humans, particularly their owners, to gain acceptance as a member of the family (flock). If they hear a word or phrase repeatedly, they might interpret that as a vocalization distinct to their flock. They then attempt to make the vocalization themselves to maintain their membership of that flock. If the parrot gets no response when it squawks a natural parrot vocalization, but receives attention or food when it mimics human speech, it has an extra incentive to repeat human words and phrases.

Wikipedia: Talking bird

Budgies are active and very curious.

video embedded from Lost in the Wild Canada on YouTube

Did you notice the bird ran some apps on the cell phone by licking the screen?!?

And then there’s “Hey, Siri!”

video embedded from Kiwi and Pixel the Parakeets on YouTube

For more budgie videos, see Kiwi and Pixel the Parakeets on YouTube.


p.s. Paul Hess writes: I wanted to mention my experience with captive budgies in west-coastal Florida as far back as annual visits with my grandmother during the late 1950s — e.g., One of her cage birds learned my name and greeted me perfectly in subsequent visits a year apart. Bill Pranty, an old friend since his teen years in Pittsburgh and now a prominent ornithologist in FL, urged me to write about this budgie’s extraordinary long-term memory. I never got around to it.

Listen for the Warning: How Many Dees?

Black-capped chickadees, 2012 (photo by CheepShot via Wikimedia Commons)

13 November 2024

When chickadees are upset they say dee-dee-dee-dee-dee but their message is different depending on predator size. As reported in a 2005 study of black-capped chickadee alarm calls:

The larger a predator’s wingspan or body length, the fewer “dee” sounds the chickadees used in their alarm call, the study found. The opposite was true for smaller predators –– the songbirds would use more “dee” sounds if they encountered a smaller bird, which could be greater threats to chickadees since they are more agile.

CNN: Crows can count up to four, a new study finds

When chickadees see a red-tailed hawk they give a warning but these hawks are large, relatively slow, and unlikely to capture a chickadee.

Red-tailed hawk (photo by Steve Gosser)

So the chickadees slow down their warning dee’s … like this.

On the other hand, northern saw-whet owls are small and agile, just the right size to capture chickadees. You can see how small they are as I held one at an owl banding in 2016.

TWO northern saw-whet owls (photo by Donna Foyle)
TWO northern saw-whet owls, 26 Oct 2016 (photo by Donna Foyle)

So when a chickadee sees a saw-whet owl …

Northern saw-whet owl (photo Kameron Perensovich via Flickr Creative Commons license)

… his warning call is frantic … like this.

By the way, the chickadee warnings in this audio were recorded at State Game Land No 203 in Wexford, PA while the birds were alarming at an Eastern Screech-owl. Screech-owls are another dangerous predator of chickadees.

When you hear chickadees, listen for their warning calls to tell you how big the predator is.

If I could find some frantic chickadees, I might find an owl.

Suddenly You’ll See a Lot of Crows

Crows at the roost, 30 December 2023 (photo by Kate St. John)

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.

Winter crow flock flies to the roost, Pittsburgh, 1 Nov 2024 (video by Kate St. John)

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.