Crows Understand Death And Threat Of It From Predators
What do intellignet birds like crows unerstand about death and the threat of death? Those questions and other like it were what researchers from the University of Washington (UW) attempted to find out in a recent study that centered on crows. The inky black birds were used for the study because they are very intelligent animals that use tools, create, and learn how to solve puzzles – which inspired one of Aesop's Fables. And they never forget a threatening face.
For his study, doctoral researcher Kaeli N. Swift created a unique way of testing how crows respond to threats and death. To begin the experiment, Swift delivered food to a particular spot each day so the crows learned to congregate there. Next, volunteers confronted the birds using a taxidermy crow or pigeon that was arranged in a pose suggesting it was dead. They also used taxidermied red-tailed hawks – known for preying on crows – posing them branches. Volunteers were masked to ensure variations in their expressions would not affect the crows' alarm responses.
"I was always the friendly feeder, which was nice. I never made any crow enemies. I would put my food out, then this second person would show up," Swift told BBC. "They [the masked volunteers] would be holding a dead crow, not violently, not reenacting a death scene, just holding it like they were picking it up to throw it in rubbish, palms outstretched like you might hold a plate of hors d'oeuvre."
When the masked person first approached carrying a "dead" crow, the birds abandoned the food Swift laid out and mobbed or scolded what they thought was a potential predator. But the crows barely reacted when volunteers carried a "dead" pigeon. Researchers also found that if a "live" hawk was placed near the crows, the birds were even more likely to avoid the food, suggesting they associated the hawk with danger.
Following one of these encounters, the crows took more time surveying the area before approaching food. They even appeared to remember the masks because they continued to scold the person whenever they appeared for up a period of approximately six weeks.
The study, recently published in the journal Animal Behaviour, suggests crows not only react to their fallen brethren, but will avoid an area or thing deemed dangerous.
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