Red-flanked bluetail

The red-flanked bluetail (Tarsiger cyanurus), also known as the orange-flanked bush-robin, 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 related species, are often called chats.

Habitat

It is a migratory insectivorous species breeding in mixed coniferous forests with undergrowth in northern Asia and northeastern Europe, from Finland east across Siberia to Kamchatka and south to Japan. It winters mainly in southeastern Asia, in the Indian Subcontinent, the Himalayas, Taiwan, and northern Indochina. The breeding range is slowly expanding westwards through Finland (where up to 500 pairs now breed), and it is a rare but increasing vagrant to Western Europe, mainly to Great Britain.<ref name=Hoyo>Template:Cite book</ref><ref>British Birds Rarities Committee occurrences, 1950-2006</ref><ref>Hudson, N. et al. (2009). Report on rare birds in Great Britain in 2008. British Birds 102: 572–573.</ref> There have also been a few records in North America, mostly in western Alaska as well as one on San Clemente Island off the southern California coast<ref>National Geographic (1999). Field Guide to the Birds of North America 3rd ed. Template:ISBN.</ref><ref>eBird: Red-flanked Bluetail in California (Dec 2011)</ref> and one overwintering on the Central California coast in Santa Cruz, California, in 2023.<ref>eBird:eBird Checklist S131890156</ref> One was also spotted in New Jersey in December 2023.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Description

At 13–14 cm long and 10–18 g weight, the red-flanked bluetail is similar in size and weight to the common redstart and slightly smaller (particularly with a slimmer build) than the European robin. As the name implies, both sexes have a blue tail and rump, and orange-red flanks; they also have a white throat and greyish-white underparts, and a small, thin black bill and slender black legs. The adult male additionally has dark blue upperparts, while females and immature males are plain brown above apart from the blue rump and tail, and have a dusky breasts. In behaviour, it is similar to a common redstart, frequently flicking its tail in the same manner, and regularly flying from a perch to catch insects in the air or on the ground. The male sings its melancholy trill from treetops. Its call is a typical chat "tacc" noise. The nest is built on or near the ground, with 3–5 eggs which are incubated by the female.<ref name=Hoyo/><ref name=Collins>Svensson, L., Mullarney, K., & Zetterström, D. (2009) Collins Bird Guide, ed. 2. Template:ISBN, pages 260–1</ref>

Taxonomy and nomenclature

The genus name Tarsiger is from Ancient Greek tarsos, "flat of the foot" and Latin gerere, "to carry". The specific cyanurus is also derived from Greek, the roots being kuanos, "dark-blue", and oura, "tail".<ref>Template:Cite book</ref>

In the past generally treated as comprising two subspecies, T. c. cyanurus breeding in northern Asia and T. c. rufilatus breeding in the Himalaya, it is now increasingly being treated as monotypic, with T. c. rufilatus split off as a distinct species, Himalayan bluetail T. rufilatus. The species has also been known by a variety of English and scientific names in the ornithological literature.

The subspecies albocoeruleus, distributed in north-central China, was described by Wilhelm Meise in 1937.<ref>Template:Cite journal</ref> It was usually considered invalid, until recognized by Hadoram Shirihai and Lars Svensson in 2018,<ref>Template:Cite book</ref> and it is now proposed to be a full species, the Qilian bluetail (T. albocoeruleus), in a molecular phylogenetic study published in 2022. It is distinctive in genetics and vocalisation, but only marginally different in morphology. The males of albocoeruleus have bluer fore-supercilium, and less white than in cyanurus.<ref>Template:Cite journal File:CC-BY icon.svg Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.</ref>

The table below details the treatments adopted by some major works, by publication date (newest first):

Publication	English name	Scientific name	Taxonomic notes
IOC standard list, version 2.5<ref>IOC World Bird List, version 2.5 (2010). Family Muscicapidae</ref>	Red-flanked bluetail	Tarsiger cyanurus	monotypic; excludes rufilatus
Collins Bird Guide<ref name=Collins/>	Red-flanked bluetail	Tarsiger cyanurus
IOC standard list, version 1<ref>Gill, Frank and Minturn Wright (2006) Birds of the World: Recommended English Names Template:ISBN, page 175</ref>	Red-flanked bluetail	Tarsiger cyanurus	polytypic; includes rufilatus
Clements Checklist (6th edition)<ref>Clements, James F. (2007) The Clements Checklist of Birds of the World 6th edition Template:ISBN, page 456</ref>	Red-flanked bluetail	Tarsiger cyanurus	polytypic; includes rufilatus
Birds of South Asia<ref>Rasmussen, Pamela C. and John C. Anderton (2005) Birds of South Asia. The Ripley Guide Template:ISBN, volume 2, page 394</ref>	Northern red-flanked bush-robin	Tarsiger cyanurus	monotypic; rufilatus split off
HBW<ref>del Hoyo, Josep, Andy Elliot & David Christie (2005) Handbook of the Birds of the World volume 10 Template:ISBN, pages 754–5</ref>	Orange-flanked bush-robin	Tarsiger cyanurus	polytypic; includes rufilatus, although split suggested
Howard & Moore (3rd edition)<ref>Dickinson, Edward C. (2003) The Howard and Moore Complete Checklist of the Birds of the World 3rd edition Template:ISBN, page 677</ref>	Orange-flanked bush robin	Luscinia cyanura	polytypic; includes rufilatus
OBC Checklist<ref>Inskipp, Tim, Nigel Lindsey and William Duckworth (1996) An Annotated Checklist of the Birds of the Oriental Region Template:ISBN, page 144</ref>	Orange-flanked bush robin	Tarsiger cyanurus	polytypic; includes rufilatus
Howard & Moore (2nd edition)<ref>Howard, Richard and Alick Moore (1991) The Howard and Moore Complete Checklist of the Birds of the World 2nd edition Template:ISBN, page 316</ref>	Red-flanked bluetail	Tarsiger cyanurus	polytypic; includes rufilatus
BWP<ref>Cramp, S. (1988) The Birds of the Western Palearctic volume 5. Template:ISBN</ref>	Red-flanked bluetail	Tarsiger cyanurus	polytypic; includes rufilatus
Voous<ref>Voous, Karel H. (1977) List of Recent Holarctic Bird Species Template:ISBN, page 43</ref>	Red-flanked bluetail or orange-flanked bush robin	Tarsiger cyanurus	polytypic; includes rufilatus