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Birds by name

Red-breasted merganser

Conservation status: Green

These handsome diving ducks belong to the sawbill family, so called because of their long, serrated bills, used for catching fish. Their diet of fish such as salmon and trout has brought them into conflict with game fishermen. At home on both fresh- and saltwater, red-breasted mergansers are most commonly seen around the UK's coastline in winter. They are gregarious, forming flocks of several hundred in the autumn.

Overview

Latin name

Mergus serrator

Family

Swans, ducks and geese (Anatidae)

Where to see them

The UK breeding population is concentrated in the north-west of Scotland, England and Wales, and in parts of N Ireland. RSPB reserves with red-breasted mergansers in winter include: Morecambe Bay, Lancs; Langstone Harbour, Hants; Exe Estuary, Devon; Arne, Dorset; Snettisham and Titchwell Marsh, Norfolk; Lough Foyle, Co Londonderry; Belfast Lough, Co Antrim; Culbin Sands, Highland; Udale Bay, Highland.

When to see them

UK birds start to flock on the coast from July, reaching a peak in December. Birds from N Europe also arrive in late autumn. They return to the breeding areas in March.

What they eat

Fish

Population

EuropeUK breeding*UK wintering*UK passage*
-2,370 pairs8,400 birds-

* UK breeding is the number of pairs breeding annually. UK wintering is the number of individuals present from October to March. UK passage is the number of individuals passing through on migration in spring and/or autumn.

Distribution

Key

Please note that the map is only intended as a guide. It shows general distribution rather than detailed, localised populations.

Illustrations

Audio

Ruud van Beusekom, Xeno-canto

Characteristics

Red-breasted merganser (female)

Red-breasted merganser - female
  • Colouring: Female
  • Size: between pigeon-mallard
  • Feather colours: brown, black, white, grey, cream/buff
  • Beak colours: black/dark grey, orange, red/pink
  • Beak length: long
  • Beak thickness: long
  • Beak shape: long
  • Leg colour: orange, red
  • Behaviour: part of flock, on ground, bird walks/runs on the ground, dives underwater

Red-breasted merganser (male)

Red-breasted merganser - male
  • Colouring: Male
  • Size: between pigeon-mallard
  • Feather colours: brown, black, white, grey, cream/buff, green
  • Beak colours: black/dark grey, orange, red/pink
  • Beak length: long
  • Beak thickness: long
  • Beak shape: long
  • Leg colour: orange, red
  • Behaviour: part of flock, on ground, bird walks/runs on the ground, dives underwater

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