 They are all highly aquatic species with webbed feet and the capacity to stay submerged for long periods of time.The snake-necked species (genera "Chelus", "Chelodina", and "Hydromedusa") are largely strike-and-gape hunters or foragers feeding on fish, invertebrates, and gastropods.The short-necked forms are largely herbivorous or molluscivorous, but are also opportunistic, with several species having specialized to eating fruits.