Anjouan sparrowhawk

Anjouan sparrowhawk
Illustration from 1864
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Accipiter
Species: A. francesiae
Subspecies: A. francesiae pusillus
Trinomial name
Accipiter francesiae pusillus
(Gurney, 1875)
Synonyms
  • Accipiter francesii pusillus (lapsus)
  • Astur francescii pusillus (lapsus)

The Anjouan sparrowhawk (Accipiter francesiae pusillus), also known as Anjouan Island sparrowhawk, Ndzuwani goshawk or Joanna Island goshawk is a subspecies of Frances's sparrowhawk (Accipiter francesiae). It is endemic to the Comoros island of Anjouan. It was thought to be extinct until searches in the 1980s and in 2005 confirmed that it is still extant.

Description

Both sexes of the Anjouan sparrowhawk resemble the male of the nominate race of Frances's sparrowhawk from Madagascar, but are markedly smaller and lack most of the barring on the underside. Males have a wingspan of 135–149 millimetres (5.3–5.9 in) and a tail 99–188 mm (3.9–7.4 in) long, while females are larger, having a wingspan of 155–163 mm (6.1–6.4 in) and a tail length of 113–125 mm (4.4–4.9 in). Both sexes have white underparts, grey upperparts, dark-greyish wings, and dark barring on the tail.[1]

Status

Due to extensive hunting and habitat loss during the 20th century, the Anjouan sparrowhawk became extremely rare by the late 1950s. Only one individual was found in a month-long survey in 1958 and the population was estimated at between one and ten birds.[2] Another expedition in 1965 spent 3 days on Ndzuwani without encountering the bird (although no dedicated effort was made, and the sparrowhawk's key habitat was not visited); the authors remarked that other subspecies were "extremely tame".[3]

In the period until 1907, 44 specimens were taken,[4] one of which is on display in the Zoological Museum of the University of Zurich, Switzerland. The last population lived in the mountainous central uplands, but between 1958 and 1977, no sightings were made.[4]

Other subspecies of Frances's sparrowhawk on other islands in the Comoros have not suffered the same losses.[5] One possible cause is the deforestation caused by human overpopulation; A. f. griveaudii has declined recently on Grande Comore,[4][5] coinciding with a significant increase in the human population, while A. f. brutus is still common on Mayotte where extensive lowland forest remains,[5] and human population density is around 75% of that on Ndzuwani.

One individual is seen in the BBC series "Unknown Africa Episode 1: The Comoros" when the film crew is taken to a remnant rain forest patch on Anjouan by the director of Action Comores in search of Livingstone's Flying Fox.

References

  1. James Ferguson-Lees & David A. Christie (2001). Raptors of the World. Boston: Houghton Mifflin. ISBN 0-618-12762-3.
  2. Constantine Walter Benson (1960). "The birds of the Comoro Islands: results of the British Ornithologists' Union centenary expedition". Ibis 103: 5–106. doi:10.1111/j.1474-919X.1960.tb03677.x.
  3. A. D. Forbes-Watson (1969). "Notes on the birds observed in the Comoros on behalf of the Smithsonian Institution" (PDF). Atoll Research Bulletin 128: 1–23.
  4. 1 2 3 Warren B. King (1978–1979). Red Data Book 2: Aves (2nd ed.). Morges, Switzerland: IUCN.
  5. 1 2 3 Alan C. Kemp (1994). "104. Frances's Sparrowhawk". In Josep del Hoyo, Andrew Elliott & Jordi Sargatal. Handbook of Birds of the World, Volume 2: New World Vultures to Guineafowl. Barcelona: Lynx Edicions. p. 149, pl. 11. ISBN 84-87334-15-6.
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