I believe this to be a white morph of the Pacific Reef Heron because on few occasions it was perched beside the dark morph... it could be Intermediate egret... Possibly!!! But if I am right then another lifer!!! The Pacific Reef Egret displays non-sexual dimorphism, with the majority being dark/charcoal grey, and a minority being white. I am open to suggestions and corrections so please be free to give your opinions!!!