Definitions

encroaches upon

Fuerteventura Chat

The Fuerteventura Chat (Saxicola dacotiae) formally known as Canary Islands Chat due to its once widespread distubution on the islands is a small passerine bird that was formerly classed as a member of the thrush family Turdidae, but is now more generally considered to be an Old World flycatcher, Muscicapidae. It, and similar small European species, are often called chats. It is an all-year resident bird, today only found on Fuerteventura in the Canary Islands, where it is known as caldereta.

This species has for some time been included in the "Common Stonechat" (Saxicola torquata), but it is well distinct; it is in all probability an insular derivative of ancestral European Stonechats that diverged some 1-2 mya, approximately during the Early Pleistocene (Wink et al. 2002).

Description

Generally, it appears somewhat intermediate between the closely related European Stonechat, and the Whinchat, and its body size and shape is reminiscent of a lithe European Robin. Its upperparts are generally colored like in the Whinchat, but more contrasted, dark brown with a blackish head and back streaks. It has a purer white supercilium reaching behind the eye and white neck sides, and a light orangey-chestnut breast becoming duller and paler on the underside towards the whitish belly. The rump and tail are dark, the latter with a white pattern visible in flight. There is also a white wing band. The female is similar to a washed-out version of the male, with a brown, black-streaked head and no white neck patches.

The male has a ticking call like a pebble hitting another, and a high twittering song like a European Stonechat.

Ecology

This species is highly faithful to good habitat. Its main occurrence and only breeding habitat is in barrancos, ravines and rocky slopes with fairly sparse (30-50% open ground), shrubby vegetation (Illera et al., 2006). Although they sometimes also venture into more open and arid areas such as malpaís (old lava flows with resurgent vegetation), the species prefers copses of palm trees and shrubs (Álamo Tavío 1975) such as the aulaga Launaea arborescens, the saltwort Salsola vermiculata and the boxthorn Lycium intricatum (BirdLife International 2004). Males sing from exposed perches, from where the birds also like to hunt insects on the wing; occasionally, they venture into fields or gardens for feeding. Completely open habitat appears only to be utilized when gathering food for their young (BirdLife International 2004).

Laying 4-5 eggs per clutch and incubating for 13 days, it usually manages to raise 2 clutches of young per year.

Conservation status

This species is now considered Endangered, as construction, mainly tourism-related, encroaches upon the best habitat (Illera et al., 2006). The population is hard to estimate, but most probably between 1.300 - 1.700 mature birds (BirdLife International 2004), and recognizably declining for some time already. In particular, heavy land clearance has occurred more recently on the Jandía peninsula, isolating the local subpopulation and making it vulnerable to adverse effects of small population size.

Desertification, exacerbated by grazing goats and locally sinking water tables, also contributed to habitat loss; feral cats and Black Rats prey on the species and especially its eggs and young. A conservation action plan exists for this species since 1999 (BirdLife International 2004); due to its fairly high reproductive rate, if enough habitat is secured and predators are kept at bay, the species should be able to hold its own.

The Chinijo Chat, subspecies murielae from the Chinijo Archipelago near Lanzarote, became extinct in the early 20th century, as usually claimed mainly due to deteriorating habitat quality but perhaps more due to persecutions of introduced predators. Peculiarly, the species was not reported to inhabit Lanzarote itself.

References

  • Álamo Tavío, Manuel (1975): Aves de Fuerteventura en peligro de extinción. In: Asociación Canaria para Defensa de la Naturaleza (ed.): Aves y plantas de Fuerteventura en peligro de extinción: 10-32. Las Palmas de Gran Canaria. PDF fulltext
  • Database entry includes a range map, a brief justification of why this species is endangered, and the criteria used
  • BirdLife International (2006): Species factsheet: Saxicola dacotiae Retrieved 2006-DEC-12.
  • Illera, Juan Carlos; Díaz, Mario & Nogales, Manuel (2006): Ecological traits influence the current distribution and range of an island endemic bird. J. Biogeogr. 33(7): 1192–1201. (HTML abstract)
  • Wink, M.; Sauer-Gürth, H. & Gwinner, E. (2002): Evolutionary relationships of stonechats and related species inferred from mitochondrial-DNA sequences and genomic fingerprinting. Brit. Birds 95: 349-355. PDF fulltext

External links

Search another word or see encroaches uponon Dictionary | Thesaurus |Spanish
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature