A rare, all-black, diving seaduck, called a Common Scoter, is an exciting new sighting at RSPB Geltsdale

Common Scoters have been seen on the tarn at RSPB Geltsdale this spring. This dark, diving seaduck is often seen in large groups, bobbing offshore and feeding far out to sea, or flying inCommon Scoter by Adam Moan long, straggling lines, low along the water near the coast. The numbers of Common Scoters have decreased substantially and winter populations are vulnerable to oil spills and pollution, so the species is classified as Red in the UK under the Birds of Conservation Concern. It can be seen offshore in the UK at all times of year, but is principally a winter visitor.

Wildlife enthusiast Adam Moan caught a male Common Scoter on camera at the reserve - his pictures show its distinctive, black, glossy feathers and chunky beak. Male Common Scoters are the UK’s only all-black duck, with brown legs and a thick beak with a large, black, raised knob at the base and a yellow wedge on top. Females, meanwhile, are browny-grey, with brown legs, a paler cheek and underwing and a blackish bill. Juveniles are also brown with a paler cheek and underwing.

Common Scoters can dive up to 30 metres deep to hunt for shellfish, and keep their wings partly open underwater to help balance them. They measure between 44 and 54 cm in length, weigh 650g to 1.3 kg and have a wingspan of 79 to 90 cm. There are just 52 known breeding pairs in the UK, although 135,000 birds winter here. In the breeding season, Common Scoters nest in single pairs, building a nest on the ground near water, which they line with lichen, grass and moss. Females lay six to 11 large, buff-coloured eggs, which they incubate for 27 to 31 days. Chicks are able to feed and swim soon after hatching and can fly at around 45 days, fledging at 45 to 50 days.