Humpback whales have been seen off Sumburgh Head for a short period in most recent summers. They have often been seen jumping almost clear of the water, with a mighty splash. Whaling began in Shetland waters in 1903 and by 1929 the humpback was almost extinct locally. Their re-appearance suggests that stocks are slowly recovering.

Looking for whales and dolphins requires patience and a great deal of luck. A high vantage point and calm sea increase the chances of success. Look carefully for tell tale signs fins breaking the surface or a whale blow. Once you spot a cetacean you will probably need binoculars identify it.

Grey seals pup in October, on exposed, inaccessible beaches. The pup's fluffy white coat is moulted after a month and they can then enter the sea. Grey seal milk is 50% fat and pups grow very quickly, being weaned at about 3 weeks having gained 15-45 Kg in weight - an energy intake equivalent to approximately 70 cream buns per day! Whilst females are busy suckling young, the dominant male patrols the beach looking after his harem. He will attempt to mate with all his females about 3 weeks after they give birth. The fertilised egg is implanted 3 months later and the foetus starts to develop.

In most of Europe otters are freshwater animals but in Shetland they have adapted to a marine existence. The sea provides a plentiful supply of their favourite foods, fish and crabs, but freshwater is also crucial to wash salt out of their fur so as to maintain its insulative property.

The minke whale (herring hog) is the commonest baleen whale in Shetland waters. About 8 metres long, they are frequently seen from Sumburgh Head in June and between Fetlar, Whalsay and Out Skerries during July and August. The tall sickle shaped fin is situated well back on the blackish body and the blow is rarely seen.

Killer whales or Orcas are often seen in Shetland most frequently from Sumburgh Head and in Mousa Sound, where they feed on shoaling fish and hunt seals. The Shetland Sea Mammal Group is trying to find out more about Shetland's Orcas and would be pleased to receive photographs or video of animals.

The harbour porpoise (known locally as a neesick), is the smallest and most frequently seen cetacean in Shetland. The short triangular fin breaking the surface is usually all that is seen. Mouse, Noss and Yell Sound are good places to look for them. Numbers increase in summer when animals move inshore, often accompanied by newly born calves, to feed on shoaling fish especially sandeels.

White-sided dolphins, usually a deeper water species, lack the pale saddle shown by white-beaked. In late summer small groups occasionally enter voes such as Weisdale and Whiteness, remaining for several days if sufficient food is present.

Risso's dolphins are distinctive if seen well as they lack a beak and often look pale grey. Two other dolphin species, common and striped, are rare visitors to Shetland normally being associated with warmer waters.

Pilot whales (known locally as a caain whale) used to be a much more common site in Shetland and herds were once actively driven ashore (caa'd) and killed, as remains the case in Faroe today. The largest known caa was at Quendale in the south mainland when 1540 animals were driven ashore. The last was at Weisdale in 1903 when 83 were killed.