Common merganser
| Common merganser Temporal range:  | |
|---|---|
| M. m. merganser, male in Sandwell, England | |
| M. m. americanus, female | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Class: | Aves | 
| Order: | Anseriformes | 
| Family: | Anatidae | 
| Genus: | Mergus | 
| Species: | M. merganser | 
| Binomial name | |
| Mergus merganser | |
| Subspecies | |
| 3, see text | |
| M. merganser range   Breeding   Resident   Passage   Non-breeding | |
| Synonyms | |
| Merganser americanus Cassin, 1852 | |
The common merganser (North American) or goosander (Eurasian) (Mergus merganser) is a large sea duck of rivers and lakes in forested areas of Europe, Asia, and North America. The common merganser eats mainly fish. It nests in holes in trees.