Double Crested Cormorant, Nannopterum auritum. Common and widespread, breeding in central North America, wintering in the south, and found year-round along the west coast and Florida. Their diet consists of fish, crustaceans, and invertebrates from fresh or salt water. Despite being water birds, and even diving for their prey, Cormorants' feathers are not fully water-proofed and have to frequently air out their feathers. Their numbers were once threatened by the use of DDT, a pesticide that is known to cause environmental damages, but have rebounded since the discontinuation of it. Double Crested Cormorants are not sexually dimorphic but do each express a breeding and non-breeding plumage.