Contrary to some of the new age "omens mean whatever rainbow sparkly feel good woo I want them to mean" claptrap, crows are a straight up an omen of death. Since they're proliferating in your town, it's possible Death is going to make a few extra visits to your town this year. Does it mean that death will visit you and your family soon? No, not necessarily. You should do your own divinations and meditations where that is concerned if you really want to know.

Good on you for actually noticing animal behavior patterns. I wouldn't worry about it -- because of the vaccines bringing up the rate of all-cause mortality, the Reaper has already started working overtime and will soon be putting in double shifts. The crows are a mere portent of the obvious.