The hooded merganser is a diving duck with a distinctive fan-like hood on the back of the head. It lives on freshwater lakes, wooded wetlands and tidal shallows throughout the Chesapeake Bay watershed from autumn through spring.
Male and female mergansers have different patterns and coloring. Males are mostly black with rusty brown sides. They have a white, fan-like hood; a white wing patch; small, yellow eyes; and a white breast with two black bars on either side. Females are dark gray or brown with a dusky brown head and chest. Their hood is cinnamon-colored. Immature males look similar to females. Bills are long and serrated; males have a black bill and females have a brownish bill. The hooded merganser can raise or lower its hood. They grows to 13 to 19 inches with a wingspan of about 26 inches; emales are smaller than males.
These ducks live on freshwater ponds, lakes and wooded swamps in autumn and spring. In winter, they can also be found on shallow fresh and brackish waters on the Chesapeake Bay and its tidal creeks and rivers.
Mergansers visit the Bay watershed mostly in spring and autumn. There are some local winter and summer populations in the region.
The hooded merganser eats a variety of aquatic creatures, including fish, insects, crabs and crayfish. It usually feeds during the day. It dives underwater to look for and reach its prey, which it captures with its serrated bill. Its extremely muscular gizzard allows it to digest the hard exoskeletons of some shellfish.
Humans hunt hooded mergansers.
This duck takes off by running across the water’s surface and flapping its wings. In flight, all mergansers hold their bill, head, body and tail straight. They land on the water by “skiing” across the surface to slow down.
The merganser's call is a low, croaking grunt.
Breeding occurs mostly in Canada and the Midwest. Some hooded mergansers breed locally in parts of Maryland in March and April. They nest in tree cavities or artificial nest boxes near water. Females lay 5 to 10 glossy, white eggs that hatch in about 33 days. The male abandons the female after she has finished laying her eggs. If the female is disturbed while incubating her eggs, she will abandon her nest. Females can often lay a new clutch if predators eat her first one. One day after her ducklings hatch, the female leads them out of the nest to the nearest water body. The ducklings are able to dive for food and feed themselves. Ducklings fledge by the time they are 10 weeks old.