The male red-breasted merganser boasts a vibrant appearance with a glossy green/black head and reddish breast, whilst the female displays a subtler grey body with a reddish-brown head, making them equally charming to observe.
The red-breasted merganser is one of three ‘sawbill’ species regularly found in the UK. It is closely related to the larger common merganser, or goosander, and the red-breasted merganser is found across the northern hemisphere. While the common merganser prefers freshwater lakes and rivers, its red-breasted cousin is more at home in saltwater environments, frequenting shallow tidal waters where it dives for fish. Numbers increase significantly in winter as birds arrive from further north, sometimes exceeding 10,000 individuals. Some individuals remain on the coast year-round to breed.
The red-breasted merganser is a specialist fish hunter. This agile diver uses its serrated bill (of which it is named after) to capture small fish and invertebrates beneath the water’s surface.
They are typically seen in small groups, sometimes engaging in spectacular courtship displays as the breeding season approaches. Though relatively silent, male red-breasted mergansers put on an elaborate courtship display. Pair formation begins in mid-winter, intensifying as spring migration approaches. Both sexes have distinctive spiky crests, though in non-breeding (eclipse) plumage, males resemble females but retain their white wing patches.
