flock

Multiple birds (near always the same species) behaving as a group. Distinct from too_many_birds in that the birds must be a grouping in some way (Eg, being clustered together or flying together), for instance a pet store featuring countless cages with a few birds each or a series of taxidermy animals would be not count as flock but could be too_many_birds.

Too_many_birds not flock: Danbooru post #6692857 Danbooru post #6949868 Danbooru post #114802
Flock and too_many_birds: Danbooru post #6709824 Danbooru post #5779985 Danbooru post #6626571 Danbooru post #6237359

In cases where a character is surrounded by birds that appear to have been startled Danbooru post #6244855 it is generally safe to tag flock.