Small duck; feeds by diving to catch mainly fish with thin, serrated bill. Breeding males have showy black and white crest, a couple zebra stripes on their white breast, and chestnut sides. Females and immature males are brown overall with a puffy crest and a thin orange stripe along the bottom of the bill. Nests in cavities. Usually found on calm bodies of water including ponds, rivers, and lakes; rarely on ocean.