The average adult raven is about 2.5 pounds and it’s hard to tell adults from juveniles. The below video shows a power struggle between ravens at a food source. At the very beginning you can see a raven on the far left grab another raven’s tail feathers with his beak and pull him or her away from the food. Another seems to join in. (By the way, if the video is blurry find the settings in the bottom right hand corner of the player and change it to a higher resolution. Youtube automatically chooses a low setting so it will download faster.)
After reading Ravens in Winter, a book by Bernd Heinrich, I’m inclined to believe that the commotion going on in the video has to do with a power struggle (to gain access to the food) between the juvenile birds and the adults. According to Heinrich, adults are usually silent at carcasses (dead animals in the wild), and juveniles are very noisy. The juveniles “yell” at kills and make a commotion, possibly to attract more juveniles to the kill, in order to compete with the adults and gain access to the food.
Heinrich “proves” through observation and careful note-taking that ravens actively recruit other ravens to food piles. He speculates, after studying raven behavior for many years, that this recruitment is not necessarily altruistic, or done in order to get the favor back some day. Instead, it is probably related more to “gaining or maintaining access to the food than to sharing the wealth.”
Juveniles actively recruit, in order to overwhelm by sheer numbers, the adults at the carcass, so that the adults will give up defending the carcass, which they do when they are just too outnumbered.
So if we can extend this power struggle at carcasses in the field to city food (trash) then it’s possible the squawking raven in the video, the one being pulled from the food by his or her tail feathers, is likely a juvenile, being bossed around by the adults, who are not as vocal.
I strongly encourage any bird lover to read Ravens in Winter. This bird that I see nearly every day of my life is actually quite mysterious and Heinrich helps us understand their possible and likely motivations.
Thanks for reading! Happy New Year!