A fierce pirate of the sea, the great skua is renowned for stealing fish from other seabirds and dive-bombing anyone that comes near its nests. It breeds on the Scottish Isles.

The river lamprey is a primitive, jawless fish, with a round, sucker-mouth which it uses to attach to other fish to feed from them. Adults live in the sea and return to freshwater to spawn.

The Atlantic salmon spends most of its life at sea, but makes an epic journey back to the river or stream in which it hatched to spawn. Look out for it in freshwater rivers in the north and west…

The black-and-white barnacle goose flies here for the 'warmer' winter from Greenland and Svalbard. This epic journey was once a mystery to people, who thought it hatched from the goose…

The common scoter has suffered large declines in the UK, threatening its survival here. Look out for this duck feeding at sea in winter when its numbers are bolstered by migrating birds.

These energetic dolphins are often spotted in large groups which will approach boats, bowriding and leaping alongside. At sea, they can form superpods - huge groups made up of thousands of…

The eel is famous for both its slippery nature and its mammoth migration from its freshwater home to the Sargasso Sea where it breeds. It has suffered dramatic declines and is a protected species…