oh boy. Does this bring back memories. I think it's crows. I remember my aunt
was talking about something like that. She said that crows can sense death and
that when a crow is around, that means death is near. She told me the story of
when she kept seeing a crow around her house and she was getting scared. A few
days later, her neighbor died. I dunno, but that could hold some relations to
what you're asking. Or perhaps my aunt is just kooky...

Mo Po