Hawks vs crow calls: keeping my pigeons safe??

Putting my hypothesis about crow calls warding off hawks to the test. Will my racing pigeons be safe? Does it actually help keep pigeons safe?
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By Rene Grayson
#pigeons #kalapati #kobutor #racingpigeons #pigeonracing #paloma #kalapatids #pigeonlover #حمامة #pigeonhobby