On take off the attitude of the plane may be such (nose high) that the birds flying level are never seen. Furthermore the plane will likely be slow and heavy.
I didn't think about the first part, that makes a lot of sense - thanks for the reply
There are still such things as accidents. Not everything in the world is avoidable
I so agree. I wish people realized this in other areas as well, like heart surgery. I am glad that the airline industry/pilots train extensively on prevention and avoidance. Simple things like checklists would help a lot more in surgery, for instance (proven by tests).
Thanks again for the answer