Beaudouin's snake eagle

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Beaudouin's snake eagle
Flickr - Rainbirder - Beaudouin's Snake Eagle (Circaetus beaudouini).jpg
Perched adult bird near Kampanti, The Gambia.
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Accipitriformes
Family: Accipitridae
Genus: Circaetus
Species:
C. beaudouini
Binomial name
Circaetus beaudouini

Beaudouin's snake eagle (Circaetus beaudouini) is a species of snake eagle in the family Accipitridae found in the Sahel region of west Africa. It forms a superspecies with the Palearctic short-toed snake eagle Circaetus gallicus and the black-chested snake eagle Circaetus pectoralis. [2] This bird seems to be declining in numbers and the International Union for Conservation of Nature has rated it as a "vulnerable species".

Contents

Description

The bird has a wingspan of 170 cm (67 in). A large snake eagle with grey-brown upperparts, including the head and chest, contrasting with white underparts barred with brown and white vent. It has a black bill and large, bright yellow eyes with long pale grey, unfeathered legs. Juveniles are all dark. [2]

Behaviour

Normally seen on a prominent perch such as a telegraph pole or dead tree, as it is a sit-and-wait hunter, rather than in flight but generally behaviour is poorly known. The diet mainly consists of snakes and other small vertebrates. It breeds in November to March in West Africa in a small stick nest at up to 25 m (82 ft) in the top of a tree. The clutch is usually a single egg. Incubation period is probably around 45 days with a fledging period which may be a further 70 days. [2]

Habitat

Open woodlands, wooded savanna and cultivation. [2]

Distribution

In a narrow band from Guinea-Bissau, Senegal and Gambia through southern Mali and Burkina Faso, Niger, northern Nigeria and Cameroon, southern Chad, Central African Republic and South Sudan. It has been recorded in Uganda but its status is uncertain in Kenya. [3] There may be some nomadic movements, it appears to move southwards during the dry season and northwards during the rains. [4]

Status

This bird is nowhere common and has been little studied. [2] The total population is thought to be between 3,500 and 15,000 individuals. It is threatened by the results of the rising human populations in the Sahel regions. This brings about more deforestation, increase in the area under cultivation and an associated increase in the use of pesticides, overgrazing, urbanization and increased hunting pressure. Raptors are seeing declines in their populations and this species appears to be decreasing in numbers and is categorised as Vulnerable by the International Union for Conservation of Nature. [3]

Taxonomic note

Along with the black-chested snake eagle often treated as a subspecies of the short-toed eagle because of reports of mixed pairings and because Beaudouin's snake eagle is intermediate in plumage between short-toed eagle and black-chested snake-eagle. However, plumage differences are significant enough for all three to be currently regarded as three separate species within a single superspecies. [2]

Related Research Articles

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<span class="mw-page-title-main">Short-toed snake eagle</span> Species of bird

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<span class="mw-page-title-main">Brown snake eagle</span> Species of bird

The brown snake eagle is a fairly large species of bird of prey in the family Accipitridae. It is found in West, East and southern Africa. This species is an almost obligate predator of a variety of snakes. A very solitary bird, the brown snake eagle has a prolonged breeding cycle and raises a single eaglet. Although probably naturally scarce, it is classified as a least concern species as it continues to occur over a very broad range.

<span class="mw-page-title-main">Southern banded snake eagle</span> Species of bird

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The western banded snake eagle is a grey-brown African raptor with a short tail and a large head. Juveniles have paler and browner upper parts than adults, with white-edged feathers. The eagle's head, neck and breast are dark-streaked. The underparts are white with pale brown streaks, mainly on belly and thighs. Subadults may be all dark grey-brown without any streak on underparts. The eyes, ears, and legs are yellow. They have crested chests.

References

  1. BirdLife International (2018). "Circaetus beaudouini". IUCN Red List of Threatened Species . 2018: e.T22732272A129918008. doi: 10.2305/IUCN.UK.2018-2.RLTS.T22732272A129918008.en . Retrieved 12 November 2021.
  2. 1 2 3 4 5 6 Ferguson-Lees, James; Christie, David A. (2001). Raptors of the World. Christopher Helm. p. 449. ISBN   0-7136-8026-1.
  3. 1 2 BirdLife International (2013) Species factsheet: Circaetus beaudouini. Downloaded from "BirdLife International - conserving the world's birds". Archived from the original on 2007-07-10. Retrieved 2012-09-29. on 20/10/2013
  4. Brown, Urban & Newman 1982 The Birds of Africa Volume 1, Academic Press ISBN   0-12-137301-0