ARCTIC SKUAS - Western Isles Birds Sightings

Arctic skuas are the most common skua in Europe - identifiable by its pointed tail. This bird is a medium-sized seabird with pointed wings, dark with pale patches at the tips of the wings. The adults have the two long pointed feathers sticking beyond the rest of the tail as a single central prong. Juveniles lack this prong and show a variable amount of barring in their plumage.

The arctic skuas come in two very distinct forms, or "morphus" - a light morph in which the breast and belly are a pale creamy white - with yellowish cheeks - and the second type are a dark morph - with the entire underparts being chocolate brown in colour.

Both these forms are not separate races and infact they do interbreed with each other. You do get mixed pairs frequently.

as the name suggests Arctic Skuas are found around the Arctic though in fact they breed much further south. Skuas annually migrate to winter in the Southern Hemisphere

In Scotland the arctic terns breed along the coast or indeed on the open moorlands and heaths.They are vulnerable to predators such as rats and mink so this means that they frequently breed on offshore islands areas where there are no mammal predators. In winter the arctic tern stays out at sea, resting on floating objects and ice

These seabirds are sometimes referred to as avian pirates as skuas steal a lot of their food from terns and other seabirds that are carrying fish back to their nests and young

In the summer food is mostly birds, small mammals, insects - whilst on the winter its fish, mostly by piracy from other birds

In summer these birds have a loud nasal wailing noise - but at sea are silent.

These skuas breed on moorland near sea and winter at sea. They are monogamous forming lifelong partnerships - which is perhaps why they are so aggressive towards any males nearby. They nest hollow on ground in moss or heather.

There are two eggs and the skuas have only one brood between May and June. Once the young leave the nest, they may not visit land for two years—until they have themselves reached breeding age.

Arctic Skuas are also known as the Parasitic Jaeger, as they have an extraordinary habit of hunting down other seabirds - chasing then in mid air until they have dropped their catch or regurgitated it. This habit called "kleptoparasitism" means that they are feared by the other seabirds.

They will also target human intruders if they are near their nests and can hit them with their powerful feet.