Visual Search | Wizard | Browse
Bird name:

Arctic Skua

Stercorarius parasiticus

Order

CHARADRIIFORMES

Family

Skuas (Stercorariidae)

BTO 2

AC

BTO 5

ARCSK

Euring 5

05670
iBird Ad

Breeding Location:

Tundra, Moorland, Islands



Breeding Type:

Monogamous



Egg Colour:

Smooth, slightly glossy and olive to pale brown with irregular brown spots.



Number of Eggs:

1 - 4



Incubation Days:

25 - 28



Egg Incubator:

Both sexes



Nest Material:

Scrape lined with grass and moss.



Nest Location:

On ground near water



Migration:

Migratory



General

Arctic Skua: Large, gull-like bird with pointed wings, and pointed, projecting central tail fathers. Black cap, dark grey upperparts, buff nape, and white underparts except for dark vent. Bill dark gray with black tip, legs black. Sexes similar but juveniles are very different from adults and are dark or rusty coloured with fine streaking on head, fine black and rusty barring on body, can show whitish on rump, and have blunted central tail feathers.

Range and Habitat

Arctic Skua: Migrant breeder found in coastal moorlands in north Scotland, and Shetland and Orkney islands during summer breeding season. On summer passage can be found at coasts especially near tern colonies. Often visible flying over water, only comes to land to breed. Winters on southern oceans.

Breeding and Nesting

Arctic Skua: Monogamous, with pairs demonstrating site fidelity by returning to the same nesting territory year after year. Death of a mate may result in experienced breeders deferring breeding. Eggs are incubated for 25-28 days, typically by both sexes. Fledglings leave nest after 25 to 30 days.

Foraging and Feeding

Arctic Skua: Feeds on birds, small mammals, and insects during the summer. In winter feeds mostly on fish, also on eggs and young birds. Well-known as an avian pirate that will readily harass other birds and steal recently-caught fish.

Vocalisation

Arctic Skua: Usually silent; on breeding grounds utters a series of repeated two-syllable notes and a variety of mewing sounds.

Similar Species

Arctic Skua: The Pomarine Skua is larger and bulkier, has a heavier body, deeper belly, and stout neck. The Long-tailed Skua is also smaller with slimmer wings, elongated rear, longer legs, and shorter bill.

.
UnderpartsX

Belly, undertail coverts, chest, flanks, and foreneck.

UpperpartsX
Back, rump, hindneck, wings, and crown.
CapX
The area on top of the head of the bird.
NapeX
Also called the hindneck or collar, it is the back of the neck where the head joins the body.
RumpX
The area between the uppertail coverts and the back of the bird.
VentX
Birds do not have two separate cavities for excrement and reproduction like humans do. In birds, there is one single entrance/exit that suits both functions called the vent, cloaca or anus.
4 and 6 letter alpha codesX

The four letter common name alpha code is is derived from the first two letters of the common first name and the first two letters of common last name. The six letter species name alpha code is derived from the first three letters of the scientific name (genus) and the first three letters of the scientific name (species). See (1) below for the rules used to create the codes..

Four-letter (for English common names) and six-letter (for scientific names) species alpha codes were developed by Pyle and DeSante (2003, North American Bird-Bander 28:64-79) to reflect A.O.U. taxonomy and nomenclature (A.O.U. 1998) as modified by Supplements 42 (Auk 117:847-858, 2000) and 43 (Auk 119:897-906, 2002). The list has been updated by Pyle and DeSante to reflect changes reported by the A.O.U from 2003 through 2006.

Read more...
ITIS CodesX

The Integrated Taxonomic Information System (ITIS) was established in the mid-1990 s as a cooperative project among several federal agencies to improve and expand upon taxonomic data (known as the NODC Taxonomic Code) maintained by the National Oceanographic Data Center (NODC), National Oceanic and Atmospheric Administration (NOAA).

To find the ITIS page for a bird species go to the ITIS web site advanced search and report page at http://www.itis.gov/advanced_search.html. You can enter the TSN or the common name of the bird. It will return the ITIS page for that bird. Another way to obtain the ITIS page is to use the Google search engine. Enter the string ITIS followed by the taxonomic ID, for example "ITIS 178041" will return the page for the Allen's Hummingbird.

Read more...
Parts of a Standing birdX
Head Feathers and MarkingsX
Parts of a Flying birdX