# UKBirds

Back

## Red-Breasted Merganser

### Mergus serrator

The Red-breasted Merganser is a diving duck.
The adult Red-breasted Merganser is 51-62 cm (20-24 in) long with a 70-86 cm (28-34 in) wingspan. It has a spiky crest and long thin red bill with serrated edges. The male has a dark head with a green sheen, a white neck with a rusty breast, a black back, and white underparts. Adult females have a rusty head and a greyish body. The juvenile is like the female, but lacks the white collar and has a smaller white wing patch.
The call of the female is a rasping prrak prrak, while the male gives a feeble hiccup-and-sneeze display call.