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BC Conservation Data Centre: Species Summary

Mergus merganser
Common Merganser

Scientific Name: Mergus merganser Linnaeus, 1758
English Name: Common Merganser
Classification / Taxonomy
Scientific Name - Concept Reference: American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online:
Classification Level: Species
Species Group: Vertebrate Animal
Species Code: B-COME
Kingdom Phylum Class Order Family
Animalia Craniata Aves Anseriformes Anatidae
Conservation Status / Legal Designation
Global Status: G5 (Apr 2016)
Provincial Status: S5 (Mar 2015)
BC List: Yellow
Provincial FRPA list:   
Provincial Wildlife Act:
SARA Schedule:
General Status Canada: 4 - Secure (2005)
Migratory Bird Convention Act: Y
Ecology & Life History
General Description: See Kaufman (1990, Am. Birds 44:1203-1205) for information on identification.
Global Reproduction Comments: Clutch size is 6-17 (usually 9-12). Incubation lasts 28-32 days, by female. Young first fly at 60-70 days. First breeds at end of second year (Terres 1980, Palmer 1976).
Migration Characteristics:
(Global / Provincial)
    Local Migrant:
    Distant Migrant:
    Within Borders Migrant:
N /
Y /
Y /
na /
Global Migration Comments: Migration to northern breeding areas occurs mainly in March-April. Southerly migration is relatively late, mainly October into December. Some birds remain in northern areas (e.g., Great Lakes, Maritimes, New England) in winter. (Palmer 1976).
(Type / Subtype / Dependence)
Forest / Conifer Forest - Moist/wet / Unknown
Forest / Deciduous/Broadleaf Forest / Unknown
Forest / Mixed Forest (deciduous/coniferous mix) / Unknown
Lakes / Lake / Unknown
Ocean / Intertidal Marine / Unknown
Other Unique Habitats / Estuary / Unknown
Riparian / Gravel Bar / Unknown
Riparian / Riparian Forest / Unknown
Riparian / Riparian Herbaceous / Unknown
Riparian / Riparian Shrub / Unknown
Stream/River / Stream/River / Unknown
Wetland / Bog / Unknown
Wetland / Fen / Unknown
Wetland / Marsh / Unknown
Wetland / Swamp / Unknown
Global Habitat Comments: Mostly lakes and rivers; winters primarily on open lakes and rivers and brackish lagoons, rarely in marine coastal situations (AOU 1983).

Nests usually in tree cavities, also on ground and in nest boxes and cliff crevices; generally near clear waters of lakes and rivers in forested regions and mountainous terrain (AOU 1983, Terres 1980).
Food Habits: Herbivore: Adult, Immature
Invertivore: Adult, Immature
Piscivore: Adult, Immature
Global Food Habits Comments: Eats mainly fishes obtained by diving underwater; also amphibians, crustaceans, mollusks, and other invertebrates. Young initially feed on insects, caught mostly underwater. (Palmer 1976).
Global Phenology: Crepuscular: Adult, Immature
Diurnal: Adult, Immature
Provincial Phenology:
(1st half of month/
2nd half of month)
Colonial Breeder: N
Length(cm)/width(cm)/Weight(g): 64/ / 1709
Elevation (m) (min / max): Global: 
Endemic: N
Global Range Comment: BREEDS: Alaska, southern Yukon, Labrador, and Newfoundland south to central California, Arizona, New Mexico, southern Chihuahua (Brown 1990), and, east of Rockies, Minnesota, Michigan, New York, New England, and Nova Scotia. WINTERS: Alaska and southern Canada to Mexico and Florida. Also in Old World.
Authors / Contributors
Global Information Author: HAMMERSON, G.
Last Updated: Jan 20, 1995
Provincial Information Author:
Last Updated:
References and Related Literature
American Ornithologists' Union (AOU). 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, Kansas. 877 pp.
Bellrose, F. C. 1980. Ducks, geese and swans of North America. 3rd edition. Stackpole Books, Harrisburg, Pennsylvania. 540 pp.
Brown, B. T. 1990. Nesting common mergansers in Chihuahua, Mexico. Southwest Nat. 35:88-89.
Campbell, R.W., N.K. Dawe, I.McT. Cowan, J.M. Cooper, G. Kaiser, and M.C.E. McNall. 1990. The Birds of British Columbia, Vol. 1. Nonpasserines: Introduction, Loons through Waterfowl. Royal B.C. Mus. in association with Environ. Can., Can. Wildl. Serv. 514pp.
Palmer, R. S., editor. 1976. Handbook of North American birds. Vol. 3. Waterfowl (concluded). Eiders, wood ducks,diving ducks, mergansers, stifftails. Yale Univ. Press, New Haven. 560 pp.
Terres, J. K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, New York.

Please visit the website Conservation Status Ranks for definitions of the data fields used in this summary report.

Suggested Citation:

B.C. Conservation Data Centre. 1995. Species Summary: Mergus merganser. B.C. Minist. of Environment. Available: (accessed Feb 6, 2023).