Bio Facts: Merganser, Hooded
North America: coastal Canada south to Mexico and the Gulf Coast
Adult length: 15.7–19.3 in (40–49 cm); wingspan: 23.6–26 in (60–66 cm); adult weight: 16–31 oz (453–879 g). Adults have a crest at the back of the head which can be expanded or contracted. In adult males, this crest has a large white patch, the head is black and the sides of the duck are reddish brown. The adult female has a reddish crest, with much of the rest of the head and body a grayish-brown. Immatures resemble adult females. First-year males are similar to females, with the following exceptions: crest is a dull brown with a white patch, some black feathers on head and sides, bill dark, and eyes yellow.
About 10 years
In the wild, they eat fish, aquatic insects, and crustaceans; in the Zoo, they are fed a scientifically developed, commercially available pelleted waterfowl diet with fish, insects and greens.
IUCN – Least Concern
Hooded Mergansers are clumsy, but quick, flyers. They take off by running on water, and they have a ceaseless and rapid wingbeats during flight. They land at high speeds and are often seen ‘skiing’ across the water to come to a stop. They dive well, holding their wings in close to their body and propelling themselves underwater with their feet. They have been seen gathering at roost sites in large groups during the non-breeding season. Little is known about their territoriality during the breeding season.
Hooded mergansers breed from southeastern Alaska, central British Columbia and southwestern Alberta to southwestern Oregon, central Idaho and northwestern Montana; and from central Saskatchewan to Nova Scotia, south to Kansas, northern Louisiana and northern Georgia. Pair formation has been observed from November through January. Only monogamous pairs have been documented.
Females select the nest site, which is usually a cavity in a dead or live tree. Nest boxes, along with already built and abandoned nest sites, are preferred. Cavities are usually 4-15 feet off the ground. Between 7 and 15 eggs are laid shortly after the nest is completed, from late February through early June, depending on latitude, although most breeding occurs in March and April. Incubation begins after all the eggs have been laid. The male abandons the female shortly after this point. The female incubates for nearly one month, during which time she loses 8-16% of her body weight. After the ducklings hatch they usually leave the nest within 24 hours and are able to feed and dive immediately upon emergence from the nest. There is little information on parental care after hatching.
Forested wetlands, brackish estuaries and tidal creeks are preferred wintering habitats. Hooded mergansers winter along the Pacific, Atlantic, and Gulf coasts, mainly from southeastern Alaska to northern Baja California, and New England to Florida and west to northern Mexico. Most wintering hooded mergansers occur in the Mississippi Flyway.
The merganser can actually change the refractive properties of its eyes to enhance its underwater vision. In addition, the nictitating membrane (third eyelid) is very transparent and probably acts to protect the eye during swimming, just like a pair of goggles.
Hooded mergansers are the second smallest species of merganser, with only the Smew of Europe and Asia being smaller. It is also the only merganser restricted to North America (naturally anyway).
Hooded mergansers are most common in the Great Lakes region and current information suggests a stable, possibly increasing population in some areas. However, data on population size and status are tenuous due to the secretive nature of this species. Historically, populations likely suffered from habitat loss.
Jacksonville Zoo History:
The hooded merganser was part of the Jacksonville Zoo’s animal inventory from 1984 to 1994 and from 2001 to 2003. It was brought back again in 2008. The Jacksonville Zoo has successfully bred this species.