Central tail-feathers but slightly elongated; of equal breadth throughout; square at the extremities: tarsus two inches eight lines.
L. Cataractes, Temm. Man. d'Orn. torn. ii. p. 792. Cataractes vulgaris, Flem. in Edinb. Phil. Journ. vol. i. p. 99. Skua Gull, Mont. Orn. Diet, & Supp. Bew. Brit. Birds, vol. ii. p. 229. Common Skua, Selb. Illust. vol. ii. p. 514. pl. 100.
Entire length twenty-five inches; the same, central tail-feathers excluded, twenty-two inches: length of the bill one inch nine lines; of the tarsus two inches eight lines.
Head, and region of the eyes, deep brown: neck, and all the under parts, reddish ash, tinged with brown: back and scapulars dark ferruginous brown, the feathers edged at the sides with dusky brown; wing-coverts, secondary quills, and tail-feathers, brown: basal half of the primaries white; the remaining portion deep brown; the first with the whole of the outer web brown; shafts of the quills, as well as those of the tail-feathers, white: bill black, the base brownish: irides brown: orbits black: legs covered with large black scales; back part of the tarsus with very little indication of the projecting asperities which characterize the next species: claws strong and black. Obs. The plumage of this species is not subject to any important variation, either from age or season. One, which lived ten years in confinement, exhibited no tendency towards the light colour which characterizes the adult under plumage of the other species of the genus. (Egg). Olive-brown, blotched with darker brown: long. diam. two inches nine lines; trans, diam. two inches.
Met with in small numbers in the Shetland Islands, particularly in those of Foulah and Unst, where they remain the whole year. Of very rare and accidental occurrence Axv the southern parts of Britain. Montagu mentions one that was shot at Sandwich in Kent, in the Winter of 1800. Another has been since killed in Somersetshire. A bold and rapacious species, obtaining its food principally by pursuing the larger kinds of Gulls, and compelling them to disgorge the fish which they have obtained. Flight very impetuous. Breeds in large companies on high hills and unfrequented moors. Nest constructed of a few dried weeds. Eggs two in number.