Crows Can Hold a Grudge for Years (4 photos)

We've all heard that elephants don't forget who offended them, but some birds have long-term memories, too. New research shows that crows can hold a grudge for up to 17 years against those who angered or scared them. These birds are also very good at remembering faces.





The study began in 2006, when University of Washington ecologist John Marzluff covered his face with a scary mask and caught seven crows in a net.

Before releasing the birds unharmed into the wild, he placed identification rings on their feet.



In the following years, Professor Marzluff and his assistants periodically donned the mask and fed the crows around campus, recording their reactions.

One day, as the scientist recalls, he encountered aggressive behavior from the crows. Of the 53 birds he saw, 47 made loud croaking sounds, as if they were cursing at him.

Because the number of birds was much larger than the original group, the crows somehow learned to recognize people who posed a threat. They probably got this information from their parents and relatives.

After the peak of disgruntled croaking was recorded in 2013, its intensity gradually decreased. And now, in September 2023, 17 years after the beginning of the experiment, the researchers did not hear a single rude "caw" in their direction.





Dick Cheney

During the study, the team also used a neutral mask that resembled the face of then-US Vice President Dick Cheney.

Those wearing the Cheney mask fed the crows and were not violent.

In another part of the experiment, the students used a different set of masks to catch birds in the Seattle area.

Bill Pochmersky, who wore the "dangerous" mask, said, "The birds were very noisy, screaming, and it was clear that they were upset by my presence."



Previous studies have shown that crows have remarkable intelligence, including the ability to make tools and even count to four.