Long-bodied duck with a thin bill and shaggy crest. Breeding males have a dark green head, brown breast, and gray sides. Females and immature males have a brown head and gray body. Bill is dull red. Separated from Common Merganser by thinner bill, shaggier crest, and slimmer shape overall. Dives to catch fish on large bodies of water, including freshwater lakes and coastal regions. Favors saltwater more than Common Merganser.
Exotic species flags differentiate locally introduced species from native species.
Naturalized: Exotic population is self-sustaining, breeding in the wild, persisting for many years, and not maintained through ongoing releases (including vagrants from Naturalized populations). These count in official eBird totals and, where applicable, have been accepted by regional bird records committee(s).
Provisional: Either: 1) member of exotic population that is breeding in the wild, self-propagating, and has persisted for multiple years, but not yet Naturalized; 2) rarity of uncertain provenance, with natural vagrancy or captive provenance both considered plausible. When applicable, eBird generally defers to bird records committees for records formally considered to be of "uncertain provenance". Provisional species count in official eBird totals.
Escapee: Exotic species known or suspected to be escaped or released, including those that have bred but don't yet fulfill the criteria for Provisional. Escapee exotics do not count in official eBird totals.