HL, I think the geese can see the green where the red isn't as visible to them. In looking for a night light for predator hunting, predators are more "twitchy" with a green light than with a red light. Hogs aren't bothered with a green light or a red light.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).