Range/Habitat: Hooded Mergansers are found across North America in the US and Canada. They are found in small ponds and streams during the breeding season and in unfrozen lakes or shallow, protected saltwater bays in the fall/winter.
Behavior: Hooded Mergansers are diving ducks and have a very diverse diet including small crustaceans, amphibians, fish, mollusks, insects, and vegetation. Many other merganser species only eat fish. They can change the refractive properties of their eyes to find prey underwater and have an extra, transparent eyelid called a nictitating membrane that protects their eyes when underwater (like goggles).
Breeding: Like other cavity nesting duck species, Hooded Mergansers sometimes lay their eggs in the nests of other waterfowl (a practice called brood parasitism). Clutch size is between 5 and 13 eggs but nests have been found with up to 44 eggs in them! This forces non-biological mothers to raise the eggs of other females (from the same species and others). Ducklings are born precocial (well developed) and can start diving for food immediately after leaving the nest at 1 day old. They are found in pairs or small groups of up to 40 mergansers. Courtship practices include one or several females and a small group of males. Males court females by raising their crests, jerking their heads, and giving a hoarse cack. Females bob their heads and also make hoarse calls. Males abandon their mates as soon as she begins to incubate her eggs and it is not known if they meet again the following breeding season.
Conservation: Listing: Least Concern. These ducks used to be overhunted but now hunting pressure is low and their populations are stable.