md-100, that one's been thrashed to death before. The consesus is absolutely
NO!
I was interested to read
Canuckbirdstrike's contribution (as always) wherein he states that bird movements are observable on radar. I'm aware that our Wx radar transmissions are frequency optimised to detect water droplets, and return little else except highly reflective targets. Would a second radar optimised for bird density / reflectivity be feasible? If feasible, it could be a worth-while investment.
Failing that, the only way to use weather radar to avoid birds would be to seek active thunderstorms and fly through them deliberately. No self-respecting bird would fly there
Regards,
Old Smokey