Juan Fernandez Hummingbird

from Wikipedia, the free encyclopedia
Juan Fernandez Hummingbird
Juan Fernandez Hummingbird ♂

Juan Fernandez Hummingbird ♂

Systematics
Class : Birds (aves)
Order : Sailor birds (Apodiformes)
Family : Hummingbirds (Trochilidae)
Genre : Chile hummingbirds ( Sephanoides )
Type : Juan Fernandez Hummingbird
Scientific name
Sephanoides fernandensis
( King , 1831)
Female of the Juan Fernandez hummingbird

The Juan Fernandez hummingbird ( Sephanoides fernandensis ) is a species of bird in the hummingbird family (Trochilidae). The species occurs only on the island of Robinson Crusoe , which is part of the Juan Fernández Islands . Here its occurrence is limited to eleven square kilometers. The population is classified as critically endangered by the IUCN . The subspecies leyboldi which earlier on Alejandro Selkirk lived -Insel, considered extinct ( extinct ).

features

The male reaches a body length of about 12 centimeters and weighs about 10.9 grams. The female is only 10 centimeters and weighs 7.4 grams. Males and females have such a pronounced sexual dimorphism that they were previously considered to be more different species. The plumage of the male is predominantly red-brown-orange. Only the wings are dark gray. It has a red-yellow crown that looks relatively dark. There is a dark stripe between the beak and the eyes. The female has a dark green top and a bluish apex. The underside is white with thick green flecks on the neck. These green spots extend over the entire flanks.

Way of life

The hummingbird prefers to move in native vegetation. Especially during the breeding season he avoids introduced plants. Outside of the breeding season, it can also be seen on introduced plant species such as the blue eucalyptus ( Eucalyptus globulus ) or on other ornamental or garden plants. Usually he only goes to the introduced species in autumn, since only one native plant called Raphithamnus venustus flowers at this time . Another preferred plant is Dendroseris litoralis , a palm-like pachycaule plant that is only found on Juan Fernandez and is also endangered. However, it is in strong competition with the Chile hummingbird ( Sephanoides sephaniodes ) for this plant . Its preferred habitat is maquis vegetation. The bird is primarily a nectar collector. It also feeds on insects that it finds on leaves or catches in flight. Males have been observed chasing the female only 50 centimeters away and chirping as a warning. The main purpose of chirping is to scare off potential food competitors.

Subspecies

A distinction is made between the two subspecies Sephanoides fernandensis fernandensis ( King , 1831) and Sephanoides fernandensis leyboldi ( Gould , 1870). The latter was wiped out in 1908 by rats, goats and climatic changes.

Protection program

Distribution area of ​​the Juan Fernandez hummingbird

Since 2004, the organizations The Hummingbird Society , American Bird Conservancy and Juan Fernández Islands Conservancy, Oikonos - Ecosystem Knowledge have been trying to save birds from extinction as part of a protection program. The risk factors are diverse. On the one hand, the original flora of the island and thus the bird's most important food source is being destroyed by humans. The spread of exotic plants such as Rubus ulmifolius , Aristotelia chilensis and Ugni molinae are displacing the endemic luma tree ( Nothomyrcia fernandeziana ), which is an important breeding site for birds. To this end, introduced cats keep catching specimens. Farm animals such as goats or rabbits also destroy the original vegetation.

Etymology and history of research

Phillip Parker King described the Juan Fernandez hummingbird as Trochilus Fernandensis . The type specimen was king during his research in the Strait of Magellan collected. The species was later assigned to the genus Sephanoides . This name is formed from the Greek words "Stephanē στεφάνη " for "diadem, crown" and "-oīdēs οιδες " for "resembling". The word »fernandensis« refers to the distribution area, the Juan Fernández Islands . The name »leyboldi« is a dedication to Friedrich Leybold (1827–1879), who sent a collector to the island of Más Afuera to get more information about the hummingbird.

literature

  • Coral Wolf: Interactions Between Sympatric Hummingbirds on the Juan Fernandez Islands: Foraging Behavior and Competition. 2008, Diploma thesis (Master of Science)
  • Ingo Hahn, Biographical Isolation and Bioacoustics: the Juab Fernandez Firecrown, Sephanoides fernandesis. In: Bonn zoological contributions. 2007, pp. 101-103 ( zfmk.de ; PDF; 410 kB).
  • Michael S. Roy, Juan Carlos Torres-Mura, Fritz Hertel: Evolution and history of hummingbirds (Aves: Trochilidae) from the Juan Fernandez Islands, Chile. In: Ibis Volume 140, No. 2, 2008, pp. 265-273.
  • James A. Jobling: Helm Dictionary of Scientific Bird Names . Christopher Helm, London 2010, ISBN 978-1-4081-2501-4 .
  • Phillip Parker King: Several species of Birds belonging to the collection recently made by Capt. Philip P. King, RN during his survey of the Straits of Magellan, were exhibited. Other birds from the same collection had been named and characterized at the Meeting on the 14th of December: and on the present occasion Capt. King pointed out the distinctive characters of the following species which he believed to be new. In: Proceedings of the Committee of Science and Correspondence of the Zoological Society of London . tape 1: 1830/31 , p. 29–30 ( biodiversitylibrary.org [accessed February 12, 2014]).
  • John Gould: On a supposed new Species of Humming-bird from Juan-Fernandez Group of Islands . In: Annals and Magazine of Natural history including Zoology, Botany, and Geology . Series 4, volume 6 , 1870, p. 406 ( biodiversitylibrary.org [accessed February 12, 2014]).

Web links

Commons : Juan Fernandez Kolibri  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Biographical Isolation and Bioacoustics: the Juan Fernandez Firecrown. (PDF; 1.6 MB).
  2. ^ Greg Lasley pictures and information
  3. ↑ Dendroseris litoralis
  4. ^ Interactions Between Sympatric Hummingbirds on the Juan Fernandez Islands: Foraging Behavior and Competition. (PDF; 658 kB).
  5. ↑ a b c Phillip Parker King, p. 30.
  6. ↑ a b John Gould, p. 406.
  7. ↑ J. Del Hoyo, A. Elliot, J. Sargatal (Eds.): Handbook of the Birds of the World. Volume 5: Barn-Owls to Hummingbirds. Lynx Edicions, Barcelona 1999, ISBN 84-87334-25-3 .
  8. ^ Conservation of the Juan Fernández Firecrown.
  9. ^ Conservation of the critically endangered Juan Fernández Firecrown.
  10. ↑ Phillip Parker King, p. 29.
  11. ↑ James A. Jobling p. 354.