Glenn Spencer noticed the fish in American Border Patrol's guest house pond were missing. Later he spotted a Great Blue Heron perched over the pond and put two and two together. Heron's do eat goldfish.
    Spencer had a dog in the yard, put apparently she did nothing frighten the bird off. So he put a male dog with her. That seems to have worked.
    The Heron in back, but there are still some fish in the pond - Spencer spotted them hiding in their Koi Castles - put there just for this kind of threat.