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Marine Animal Encyclopedia

Red-breasted Merganser Mergus serrator

This is one the most widespread sawbill ducks—ducks that have narrow beaks with serrated edges, like the teeth of a saw. All these birds dive for fish, using their specially adapted bills to grip their slippery prey. Like other sawbills, the red-breasted merganser has an elongated body, a long neck, and orange-red legs. Males
have a metallic green head and shaggy crest, while the female’s head is rust-colored, with a less flamboyant crest. These birds breed near fresh water, but spend the winter on coasts, where the water is less likely to freeze. Females build a nest in dense cover, or in a tree-hole, lining it with down. They lay up to 11 eggs, raising a single brood a year. Red-breasted mergansers are hunted in some parts of their range in order to protect fish stocks, although there is little evidence that they actually do much harm.

Red-breasted Merganserzoom image
  • Order Anseriformes
  • Length 20–23 in (52–58 cm)
  • Weight 2–2 lb (1–1.25 kg)
  • Habitat Coasts, estuaries, lakes, rivers
  • Distribution Arctic and subarctic (breeding); temperate coasts (non-breeding)
Red-breasted Merganser habitat mapzoom image