Ravens pulling up potatoes

[james]

A friend of mine who grows potatoes in chilliwack is having problems with birds digging up and pecking chunks out of his crop. He says he has seen about a hundred ravens (not crows) in his field. Has anyone heard of ravens in such large numbers around here? My friend is wondering if they migrate at all and might disperse before the whole field is ruined, and if there is anything he can do to discourage them from flocking there in the first place. I did some googling but I thought I would ask here too.

[Ben]

Every year I do notice that they gather in fields with sometimes very large numbers. I've seen 140 in one group (https://ebird.org/checklist/S68523535)

As to migration, I don't think they move much, but my guess is that during the summer they spread out to nest but are otherwise always around.