The Arctic Skua, also known as the Parasitic Jaeger, is a medium-sized seabird well known for its aggressive nature.
Arctic Skuas can be difficult to identify, particularly when they are not in their characteristic breeding plumage. Adults have two different morphs which occur during the winter and summer. In winter, they have brown upperparts, a black cap, white collar, and occasionally display a brown breast band. This plumage is highly variable and a gloomy colour. The dark plumage is similar overall but areas on the underparts and head which were white, become a brown colour. The beak is almost black and the legs and feet are a dark bluish-grey or black. Plumage is identical in the adult male and female. Juvenile Arctic Skuas vary from very pale to very dark but most are warmly coloured with rusty shading to the flight feather fringes.
A pair of Parasitic Jaegers
Arctic Skuas fly at speeds of up to 25 mph (40 km/h)
Arctic Skuas often vocalise with each other. They also make calls whilst under attack and during aerial pursuits. The long call which is the most commonly heard is a “nyeeAh- nyeeAh- nyeeAh- nyeeAh” sound.
Parasitic Jaegers / Arctic Skua Call
Stanislas Wroza, XC487315. Accessible at www.xeno-canto.org/487315.
Arctic Skuas feed mainly on fish, other birds, eggs and rodents, although this can vary across breeding populations. They are sometimes referred to as 'Avian Pirates' due to their habit of stealing food from other seabirds, particularly from wintering birds and birds in the northern Atlantic which provide their primary food source.
Parasitic Jaeger in flight (Arctic Skua)
Arctic Skuas can be seen on breeding grounds in the Shetland and Orkney Islands during the summer and sometimes in northern and western coastal moorlands in Scotland. In spring and autumn they are passage migrants and can be seen all around the UK coast - particularly where there are large numbers of feeding terns.
Male and female adults are identical with the colour and marking of their plumage, but females are generally 15%-20% larger than males, although this is generally only apparent when birds are next to one another.
Arctic Skua coming in to land
Arctic Skuas will make their nests and breed on grassland, tundra or moorland, usually in a location near to a colony of seabirds from where they can steal food, or at a place with low nesting densities where it's easier for them to obtain food from what's on offer. The nest is usually placed on rocky or sandy terrain near to water. The female will lay a clutch of 1-3 eggs, and both males and females will take turn during the incubation period, which lasts around a month. Once hatched, the young birds will remain with their parents between two to three weeks after fledging. Parents will often leave their young unguarded whilst they go off and hunt for food together.
Nest of an Arctic Skua (Parasitic Jaeger)
The average lifespan for an Arctic Skua is around 13 years, but they can live for decades. The oldest recorded age was 34 years old.
BreedingThe United Kingdom Finland Iceland Norway Russia Sweden Faroe Islands Svalbard and Jan Mayen Islands Russia United States of America Greenland Southern Russia
Non-breedingItaly France Bulgaria Montenegro Netherlands Portugal Romania Serbia Turkey Gibraltar Sudan Iran Bahrain Kuwait Oman Saudi Arabia United Arab Emirates Uruguay British Virgin Islands Dominican Republic Guadeloupe US Virgin Islands Belize Costa Rica Fiji Micronesia Azerbaijan