Bird GuideDucks and GeeseCommon Merganser

At a Glance

This fish-eating duck is the typical merganser of freshwater lakes. Its flocks are usually small, but these may combine into big concentrations sometimes at large reservoirs. Common Mergansers living along rivers may spend hours resting on rocks or on shore. The British call this bird the 'Goosander.' In some parts of Europe, with artificial nesting sites provided, the species has become a common nesting bird along city waterfronts; this has not yet happened in North America.
Duck-like Birds, Mergansers
Low Concern
Coasts and Shorelines, Forests and Woodlands, Freshwater Wetlands, Lakes, Ponds, and Rivers, Saltwater Wetlands
Alaska and The North, California, Eastern Canada, Florida, Great Lakes, Mid Atlantic, New England, Northwest, Plains, Rocky Mountains, Southeast, Southwest, Texas, Western Canada
Direct Flight

Range & Identification

Migration & Range Maps

Migrates mostly in small groups. Adult males, on average, seem to winter farther north than females and young. Migration is late in fall and early in spring.


22-27" (56-69 cm). Male mostly white with black back, green head. Other green-headed ducks (Mallard, Shoveler) have different body pattern and shape. Red bill is thick at base, elongated and narrow toward tip. Female gray, with bright rusty head, sharp white throat. Compare to female Red-breasted Merganser.
About the size of a Heron, About the size of a Mallard or Herring Gull
Black, Gray, Green, Orange, Red, White
Wing Shape
Tail Shape
Pointed, Short, Wedge-shaped

Songs and Calls

Low rasping croaks.
Call Pattern
Flat, Simple
Call Type
Croak/Quack, Odd, Rattle


Wooded lakes, rivers; in winter, rarely coastal bays. Mainly around fresh water at all seasons. Summer: on shallow but clear rivers and lakes in forested country; avoids dense marshes and muddy waters. Winter: on lakes, large rivers; occasionally on bays along coast.



8-11, sometimes 6-13. Pale buff. Females often lay eggs in each others' nests. Incubation is by female only, 30-35 days.


May remain in nest a day or more after hatching; then they climb to cavity entrance and jump to ground. Female tends young birds for several weeks, but young feed themselves; they may survive even if abandoned quite early. Young are capable of flight about 65-70 days after hatching.

Feeding Behavior

forages by diving and swimming underwater, propelled by its feet, stroking with both feet in unison. Finds most food by sight; may swim along surface, dipping head underwater repeatedly until prey is spotted, then diving in pursuit.


mostly fish. Eats a wide variety of fish; also will eat mussels, shrimp, salamanders, rarely plant material. Adult males may swallow fish more than 1 foot long. Young ducklings eat mostly aquatic insects.


Courtship displays of male include swimming very rapidly in circles near female; suddenly stretching neck upward, pointing bill straight up, and giving soft call. Nest site is near water, usually in large tree cavity; also in crevices in rock, in holes under tree roots or undercut banks, or in nest boxes. Occasionally in buildings. Nest of wood chips or debris in cavity, plus lining of down.

Climate Vulnerability

Conservation Status

May be increasing in Europe; apparently stable in North America.

Climate Map

Audubon’s scientists have used 140 million bird observations and sophisticated climate models to project how climate change will affect the range of the Common Merganser. Learn even more in our Audubon’s Survival By Degrees project.

Climate Threats Facing the Common Merganser

Choose a temperature scenario below to see which threats will affect this species as warming increases. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.

Explore More