Viewing winter flocks of ‘calloo’ is a special Shetland experience.
The Shetland name for the long-tailed duck, calloo, is onomatopoeic and its Latin name, Clangula hyemalis, means ‘resound’ and ‘wintry’. An estimated 11,000 long-tailed ducks overwinter in the UK. Most arrive in Shetland in October and leave in April for their summer breeding grounds in northern Scandinavia and Russia.
They feed on aquatic invertebrates, mostly crustaceans and molluscs, and in Shetland can often be seen with great northern divers, feeding in sheltered bays with sandy beds.
Dense winter congregations of these sea ducks can make them vulnerable to inshore oil spills, and many were killed in Shetland following the 1978 Esso Bernicia and 1993 Braer oil spills.