I recently had a thought, this in and of itself is reason for celebration, a funny thought. Its a good thing that birds know how to swoop. The alternative would be to fall out of the sky when they got to where they were going.
Imagine a flock of ducks flying south for the winter, Hey bob, this looks like a good place to stop for the night, Yah Fred it does. Ok everybody its time to stop for the night. Several ducks look at each other and one says "God I hate this part" and they all fall out of the sky. Down below a hunter takes aim and shoots, the whole flock falls out of the sky, his retriver wets himself and passes out. The game warden takes out his ticket book and says "Sir you do know we have a bag limit around here, this is definately not your day"
Im sure you can imagine even more ideas along these lines. If you want place them in the comments here.
Later days!