As regular CFZ-watchers will know, for some time Corinna has been doing a column for Animals & Men and a regular segment on On The Track... particularly about out-of-place birds and rare vagrants. There seem to be more and more bird stories from all over the world hitting the news these days so, to make room for them all - and to give them all equal and worthy coverage - she has set up this new blog to cover all things feathery and Fortean.

Sunday 8 July 2018

Crows Are Always Jerks to Ravens, Research Confirms

A new study shows that although crows are smaller than ravens, they are almost always the aggressors when the two species interact.


LIVING ALONGSIDE A group of crows can be murder for a raven.

Across North America, common ravens are regularly harassed by gangs of crows, according to a new study published Wednesday in The Auk: Ornithological Advances. In 97 percent of reported interactions between crows and ravens, scientists report, crows were the aggressors.

This grudge match goes way back. In North America, ravens are both competitors and predators of the crow. Given the chance, brazen, jet-black ravens will happily make a meal out of a crow’s clutch of eggs. And one on one, a crow doesn’t stand a chance against a raven, which can reach up to three times a crow’s size and weight. (Read more about how ravens hold grudges against humans.)

But what crows lack in size, they make up for in numbers. Ganging up “gives crows the upper hand,” says Ben Freeman, postdoctoral fellow at University of British Columbia and lead author of the study.

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