Greetings Beachbms!
Looks a lot like a cattle egret, which we have a ton of along the Delaware Bay and Intercoastal Waterway wetlands (aka salt marsh.) The beak and leg coloration are different, but I'd guess the same family. Maybe an immature white heron? Blue herons are rapidly expanding around Philadelphia area -- maybe why I hardly ever hear frogs when fishing anymore... (We call the blue herons "dinosaur birds" because of their impressive size and massive bills!)