This is the heaviest species of skua and rivals the largest gulls, the great black-backed gull and glaucous gull, as the heaviest species in the shorebird order although not as large in length or wingspan. It is 52–64 cm (20–25 in) in length, 126–160 cm (50–63 in) in wingspan and has a body mass of 1.2–2.18 kg (2.6–4.8 lb). S. a. hamiltoni measured on Gough Island, weighed an average of 1.43 kg (3.2 lb) in 9 males and 1.65 kg (3.6 lb) in 9 females. S. a. lonnbergi measured in the Chatham Islands weighed an average of 1.73 kg (3.8 lb) in 30 males and an average of 1.93 kg (4.3 lb) in 32 females. The latter is one of the highest colony mean body mass for any living species of shorebird. Learn more about Subantarctic Skua