In the OP's case, I doubt that the game wardens would be obligated to do anything other than tell her she cannot shoot the hawk. Unless the hawk is causing huge financial loss to the poultry owner, they are not going to destroy the hawk. But, you are correct in suggesting that calling and requesting help "might" be worth her while.
Ginny, just so you know, it is illegal to bother a raptor in any manner. you can't squirt them with a hose, throw rocks at them, use a sling shot, or BB gun, traps on top of posts, bow & arrows....... A lot of people do what they think they need to do to protect their livestock, but there are times of several thousands of dollars and/or prison time if you get caught. It is even illegal to possess any body parts of a raptor, not even a feather. Also punishable by fines or jail time.