Gray hawk

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Gray hawk
Falco ardosiaceus

Falco ardosiaceus

Systematics
Class : Birds (aves)
Order : Falk-like (falconiformes)
Family : Falconies (Falconidae)
Genre : Falcon ( falco )
Type : Gray hawk
Scientific name
Falco ardosiaceus
Vieillot , 1823

The gray falcon ( Falco ardosiaceus ) is an African bird of prey and belongs to the falcon-like family (Falconidae). Its closest relatives are the banded hawk and the black-backed hawk, these three are partly placed in the subgenus Dissodectes .

description

The gray hawk is a relatively small, stocky hawk with a large, flattened head, heavy beak and rather short wings that do not reach the tip of the tail when at rest. The length of the bird is 28–33 cm with a wingspan of 58–72 cm, it has a weight of up to 300 grams. The female is 4–11% larger and 5–11% heavier than the male. The plumage of adult gray falcons is consistently dark gray with the exception of darker wing tips, slightly dark stripes on the body and the slightly branched hand wings . The feet and nasal wax skin and the bald skin around the eyes are yellow. The most similar species to the gray hawk is the slate hawk ; this has a more rounded head, the skin around the eye is less yellow and it has longer wings that reach to the tip of the tail.

Juvenile gray hawks are browner than adults, and the nasal wax skin and the skin around the eyes are greener. Juvenile black-backed falcons are very similar to them, but have a more branched tail and underswing.

In general, the gray hawk is shy and silent outside the breeding season , but has a shrill, clattering call and a rattling whistle.

Habitat and distribution area

Palm nuts

The gray falcon inhabits the savannah , open forests and forest clearings. He prefers areas with palm trees and banks, often sitting on exposed branches, telephone line poles and wires. The gray hawk is widespread in West and Central Africa , but is absent in densely forested regions including the areas of the Congo Basin . Its reach extends from eastern Ethiopia through western Kenya and Tanzania . In the south, the gray hawk reaches northern parts of Namibia and Zambia , and non-sedentary hawks have even been spotted in Malawi . The entire range of the catchment area extends over 12 million km 2 . There are trains going north in West Africa during the rainy season and southern trains during the dry season .

behavior

The gray hawk is a temporal specialist and is most active during dawn and dusk. In general, it hunts from a high branch but occasionally also in suspension. It feeds mainly on grasshoppers and small reptiles such as lizards , snakes and chameleons , as well as amphibians and worms . Other sources of food include small mammals such as bats and birds. The prey is usually caught on the ground. The gray hawk occasionally feeds on oil palm nuts and is therefore one of the few birds of prey for which a vegetable diet plays a role.

During courtship , the turtling couple make an ascending flight together. Usually the eggs are then laid in a hammerhead nest, which is often uninhabited. Occasionally, however, hammer heads are being displaced. Sometimes the gray hawks also use nests of other birds or tree hollows. There are two to five eggs in a clutch, these are whitish with reddish or brownish patterns and are incubated for 26 to 31 days . The nesting of the clutch takes place in the north of its range from March to June and from August to December in the south. The young birds fledge after about 30 days.

Danger

The Gray Hawk is not on the Red List of the IUCN and is still an unthreatened Art.

Etymology and history of research

Louis Pierre Vieillot described the gray falcon under its current name Falco ardosiaceus . The type specimen came from Senegal . Carl von Linné introduced the generic name Falco for numerous species as early as 1758 . The name is derived from the Greek words "arkhos, arkhō αρχος, αρχω " for "leader, dominate" and later from the Latin "falco, falconis, flectere" for "falcon, bend". The species name "ardosiaceus" is the Latin word for "slate-colored".

swell

Individual evidence

  1. ↑ Falco ardosiaceus in the endangered Red List species the IUCN 2015 Posted by: BirdLife International, 2012. Accessed April 6, 2016th
  2. ↑ Louis Pierre Vieillot, p. 1238.
  3. ^ Carl von Linné, p. 88f.
  4. ↑ James A. Jobling, p. 157.
  5. ↑ James A. Jobling, p. 54.

literature

  • James Ferguson-Lees, David A. Christie: Raptors of the World. Christopher Helm, London 2001.
  • Ian Sinclair, Peter Ryan: Birds of Africa south of the Sahara. Struik, Cape Town 2003.
  • Dale A. Zimmerman, Donald A. Turner, David J. Pearson: Birds of Kenya & Northern Tanzania. Christopher Helm, London 1999.
  • Josep del Hoyo , A. Elliott, J. Sargatal: Handbook of the Birds of the World. Volume 2: New World Vultures to Guineafowl. Lynx, Barcelona 1994.
  • Pierre Joseph Bonnaterre, Louis Pierre Vieillot: Tableau encyclopédique et méthodique des trois règnes de la nature . tape 3 : Ornithology . Mme veuve Agasse, Paris 1823 ( gallica.bnf.fr ).
  • James A. Jobling: Helm Dictionary of Scientific Bird Names . Christopher Helm, London 2010, ISBN 978-1-4081-2501-4 .
  • Carl von Linné: Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, Cum Characteribus, Differentiis, Synonymis, Locis . 10th edition. tape 1 . Imprensis Direct Laurentii Salvii, Stockholm 1758 ( gdz.sub.uni-goettingen.de ).

Web links

Commons : Gray Hawk ( Falco ardosiaceus )  - Collection of images, videos and audio files