in most cases ATC don't much care
Birdstrikes, and significant concentrations of birds
must be reported. Don't ask me to quote where it says so, it's one of those hazy memories from my theory exams. Might be worth getting the lowdown on this from the ATC forum.
My mate had a birdstrike on the left prop on his MEP skills test. He was too nervous to notice, but it sure caught the examiner's attention
From my mountain training, I'm told vultures spell
very bad news. They also tend to fold their wings and drop out of the sky if they see you coming, so diving not a good idea (plus in the mountains you'll probably hit the ground).