Green Group discussion

This very nice article shows that although the alala or Hawaiian crow went extinct in the wild, a careful breeding programme has produced enough birds to start returning them to the wild. I particularly like the video clips which include predator training.

My cat heard the caws from across the room and came to investigate; she started watching the birds on the screen.

https://www.care2.com/causes/endanger...

And the Caledonian crow is smart enough to make tools from memory.
https://gizmodo.com/neat-experiment-s...

A French theme park has trained crows picking up litter.
https://www.theguardian.com/world/201...

Crows picking up paper, plastic, inert materials maybe yes, but not really. People should be picking up after people. If this is a product of progress I don't need it, it's better off in the trash. Cigarette butts should be a big no no. The butts concentrate the stuff in the smoke.

I would worry that this might encourage kids to drop litter to watch the crows picking it up.

My brother who is a Scout leader (his kids are Scouts) put a pair of pictures on Facebook of the morning after two festivals - the music festival venue was strewn with all kinds of rubbish, from litter and bottles to tents. The Scout festival, you would never know anyone had been in the field.

Relevant book:
The Ravenmaster: My Life with the Ravens at the Tower of London

David Attenborough narrates as we watch crows in Japan adapting to city traffic.
2 mins YT.


https://www.youtube.com/watch?v=BGPGk...

Mystery involving the corvidae. First in a series about birds and crime.

A Rant of Ravens

Research article about how crows and other corvids managed to spread everywhere.

"In the work led by first-author Joan Garcia-Porta, a postdoctoral research associate in biology in Arts & Sciences and now a fellow in the Department of Genetics at the University of Barcelona, the authors show that crows' and ravens' incredible ability to rapidly expand and diversify across the planet was driven by a specific combination of traits.

Using specimens housed in museums across Europe and the U.S., the scientists found that they have longer wing lengths, bigger body sizes and bigger relative brain sizes compared with other Corvids.

"We hypothesize that these three very convenient combinations of traits are what allowed this group of birds to colonize and diversify across the world," Garcia-Porta said.

Longer wings means higher flying capacities that allowed the birds to disperse across the world. Big brains relative to their bodies suggest that ancestral crows and ravens were behaviorally flexible. They were smarter than other Corvids and, therefore, able to figure out how to live in a new environment, increasing their chances of survival. Their bigger body size also gave them a competitive advantage over smaller species, helping them establish in a new place."

https://phys.org/news/2022-04-brains-...

More information: Niche expansion and adaptive divergence in the global radiation of crows and ravens, Nature Communications (2022). DOI: 10.1038/s41467-022-29707-5
Journal information: Nature Communications
Provided by Washington University in St. Louis

Thanks to observant Estelle Richards for this tale.


"Yesterday I had an interesting wildlife encounter. I was looking out the window at the Vitex tree outside -- this tree has a number of dead branches, which I've left there because birds like perching on dead branches and I like watching the birds -- and saw a bird with a blue back and gray belly.

It was sitting next to a fork in the branches, and it wedged some kind of nut into the fork and was hitting it with its beak. Once the nut fell out and the bird flew down and retrieved it to continue battering at it.

When it got the shell open, it sang a little bit (in triumph I suppose), took the meat and flew away. I wanted to know what kind of bird I'd just seen, so I went to the computer to search for it.

I searched by color, size, and location, then looked at pictures and listened to audio clips of birdsong to identify it. Every time I played some birdsong, Shadow came to my desk to look for the bird. That cat has bird-murder in her heart.

The bird I saw was a Woodhouse's Scrub Jay, which is a member of the corvid family. They're supposed to be highly intelligent, and after watching the bird use the forking branch as a tool to hold the nut, I sure believe it."

The crow family includes the highly smart jay.

Some jays pass the Stanford marshmallow test with ease.

https://phys.org/news/2022-10-humans-...


"All the birds in the experiment managed to wait for the worm, but some could wait much longer than others. Top of the class was 'JayLo', who ignored a piece of cheese and waited five and a half minutes for a mealworm. The worst performers, 'Dolci' and 'Homer', could only wait a maximum of 20 seconds.

"It's just mind-boggling that some jays can wait so long for their favorite food. In multiple trials, I sat there watching JayLo ignore a piece of cheese for over five minutes—I was getting bored, but she was just patiently waiting for the worm," said Dr. Alex Schnell at the University of Cambridge's Department of Psychology, first author of the report.

The jays looked away from the bread or cheese when it was presented to them, as if to distract themselves from temptation. Similar behavior has been seen in chimpanzees and children.

The researchers also presented the jays with five cognitive tasks that are commonly used to measure general intelligence. The birds that performed better in these tasks also managed to wait longer for the mealworm reward. This suggests that self-control is linked with intelligence in jays.

"The birds' performance varied across individuals—some did really well in all the tasks and others were mediocre. What was most interesting was that if a bird was good at one of the tasks, it was good at all of them—which suggests that a general intelligence factor underlies their performance," said Schnell."

More information: Waiting for a better possibility: delay of gratification in corvids and its relationship to other cognitive capacities, Philosophical Transactions of the Royal Society B Biological Sciences (2022). DOI: 10.1098/rstb.2021.0348

This research was approved by the University of Cambridge Animal Ethics Review Committee, and performed in accordance with the Home Office Regulations and the ASAB Guidelines for the Treatment of Animals in Behavioural Research and Teaching.

Journal information: Philosophical Transactions of the Royal Society B

Provided by University of Cambridge

More on crows and their smartness.

"The experiments by both teams involved training test subjects to choose bracket pairs in a sentence made of symbols—choosing the parentheses in the sentence {()}, for example. Once the crows got the idea, the researchers then created longer sentences to see if the test subjects could still pick out the ones that were embedded. As with the monkeys, the researchers found that the test subjects could pick out the embedded characters in numbers that were greater than chance would allow."

https://phys.org/news/2022-11-crows-c...

More information: Diana A. Liao et al, Recursive sequence generation in crows, Science Advances (2022). DOI: 10.1126/sciadv.abq3356

Journal information: Science Advances

A crow and pigeon book for kids. And adults.

This Art Is for the Birds

Today I hung out a suet block with seeds stuck all around it, for my visiting wild birds. Generally this lasts a week for the starlings, tits and sparrows. I looked out a couple of hours later and the block was gone.
I went out and the string was still on the tree, tied.
I am pinning the crime on the magpies or hooded crows, which frequent the area and work in small flocks. Probably the magpies as the hoodies are not keen to come so near the house.

https://phys.org/news/2025-04-crows-g...

"Recognizing regularity in geometric shapes means being able to pick out one shape that is different from others in a group—picking out a plastic star, for example, when it is placed among several plastic moons. Testing for the ability to recognize geometric regularity has been done with many animals, including chimps and bonobos. Until now, this ability has never been observed in any creature except for humans.

Because of that, the team started with a bit of skepticism when they began testing carrion crows. In their work, the testing was done using computer screens—the birds were asked to peck the outlier in a group; if they chose correctly, they got a food treat. The team chose to test carrion crows because prior experiments have shown them to have exceptional intelligence and mathematical capabilities.

All the birds tested caught on right away. Each could pick out a star if it was placed within a group of rectangles, for example. To determine their level of skill, the researchers started showing them objects that were only slightly different: one box that was tilted slightly, for example, among others that were not. Their accuracy went down, but it was still much higher than chance."

More information: Philipp Schmidbauer et al, Crows recognize geometric regularity, Science Advances (2025).
https://www.science.org/doi/10.1126/s...
Journal information: Science Advances

I have booked to attend a book launch coming up, for Encounters With Corvids. There is a similarly named book about America but this one features the corvids in Ireland.
Neither book nor author Fionn O'Marcaigh are in the GR system yet, when they are I shall add the book.