anas-superciliosa aquatic-birds bank birds black-eye-stripe brown-duck chroicocephalus-novaehollandiae color colour common differences diversity ducks edge fauna fowl grass grassy gray-and-white grey-and-white grey-duck gulls harmonious harmony lake lakeside Larus-novaehollandiae non-threatening not-threatened Pacific-black-duck quiet relaxed relaxing resting seabirds seagulls shadows silver-gull slope sunlight sunshine together waiting water waterbirds waterfowl widespread wild-ducks wild-life