On Thursday I found another frequency for the US Fish and Wildlife Service's Savannah NWR Complex Radio System. While 172.450, 169.825, 171.650, and 172.650 were active, 171.750 was also active. Due to the very weak signal strength, I have to think that is probably one of the more southern transmitters, probably in the area of Blackbeard Island or Wolf Island (near the Darien area).
Mac McCormick, KF4LMT
kf4lmt@comcast.net