Identify species
Cormorant Phalacrocorax carbo
At 80-100cm, cormorants are the size of a large goose. They have a large body, long, thick neck, and a long sloping forehead and crown. Adults are black with white on the face and thighs through the spring. Juveniles are dark brown, with usually with pale, almost white, underparts. Some immatures also have white underparts, while others resemble adults, but without white thighs or faces. Some birds of the race ‘sinensis’ from Europe now breed in eastern Britain.
Cormorants gather at overnight roosts and at feeding sites, and nest in colonies, sometimes numbering 100 nests or more. Coastal breeding sites are on cliffs, stacks, and rocky islets. Inland breeding colonies are in trees close to food-rich lakes and rivers.
Male
Female
Goosander Mergus merganser
Goosanders are 58-66cm in size and larger than a Mallard. It’s a large-headed, long bodied, thick-necked diving duck with a slender, long, hook-tipped red sawbill. The male has a white body, which is flushed pink in winter, a black back and a dark green head. The female has a grey body, reddish-brown head (darker than a female Red-breasted Merganser) with bulbous, drooping crest, obvious white throat, brown neck and a grey breast. The juvenile resembles a dull female. In flight, the male looks black and white with black and white wings, while the female has smaller squarer white wing-patches. Moulting takes place between July and September and both sexes are flightless for about a month. In eclipse, the male resembles the female, but with larger white wing-patches.
Male
Female
Red-breasted Merganser Mergus serrator
Red-breasted Mergansers are 52-58cm in size which is the same as a Mallard. This long-bodied diving duck belongs to a group known as sawbills. They are smaller and thinner necked than Goosander with wispy crest and long, very thin, red bill. The male has a dark green head, white collar, a grey and white body and spotted chestnut breast. The female is grey with a reddish-brown head that merges with pale throat and grey neck. The juvenile resembles a dark female, but with shorter crest. In flight, the male shows white wing patches with two dark bars, whereas the female has a smaller patch with one bar. Mergansers moult between mid-July and September, with the male moulting a month earlier than the female. During moult both sexes are flightless for about a month. In eclipse, the male resembles the female, but retains much more white on wings.
