Red-breasted Merganser

Mergus serrator

  1. Wildlife
  2. Birds
  3. Waterfowl
  4. Red-breasted Merganser


The Red-breasted Merganser is a medium-sized duck and a member of a group known as the 'sawbills' after their long, narrow bills with saw-like 'teeth' which are good for gripping fish. A long, streamlined bird, the Red-breasted Merganser is perfectly shaped for swimming after fish. Red-breasted Mergansers are gregarious birds, forming flocks of hundreds of birds in winter.

How to identify

The Red-breasted Merganser is a white diving duck which can be distinguished from the Goosander by its thinner bill, grey sides, reddish-brown breast and crest of green feathers on its head.

Where to find it

Nests on lakes and rivers in the north and west of Britain. A common winter visitor to coastal waters.


When to find it

  • July
  • August
  • September
  • October
  • November
  • December
  • January
  • February
  • March

How can people help

Red-breasted Mergansers are excellent at fishing, but their diet of Salmon and Trout has brought them into conflict with fishermen making a living. The Wildlife Trusts work closely with fishermen, farmers, landowners and developers to ensure that our wildlife is both protected and provides a benefit to local people. Careful habitat management on local nature reserves is one way in which local Trusts are helping to provide areas where birds like the Red-breasted Merganser can thrive and avoid conflict. By volunteering for your local Trust you can help too, and you'll make new friends and learn new skills along the way.

Species information

Common name
Red-breasted Merganser
Latin name
Mergus serrator
Length: 50-60cm Wingspan: 78cm Weight: 1.1kg Average Lifespan: 6 years
Conservation status