01/01/2010
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Linnet and Twite

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Twites can appear more colourful than Linnets. Photo: Steve Young (www.birdsonfilm.com)
Twites can appear more colourful than Linnets. Photo: Steve Young (www.birdsonfilm.com)

Key featured species

  • Linnet Carduelis cannabis
  • Twite Carduelis flavirostris

The problem

At best described as ‘buffy’ in winter, the closely related Linnet and Twite have similar fairly drab plumages at this time of year. Location is one clue to distinguishing them; another is Twite’s slightly more colourful appearance.

The solutions

Habitat and status

The most important consideration when identifying Twite is location. As a breeding bird, it is confined to western and northern coastlines of Ireland and Scotland and upland areas of Scotland and northern England, with a few in north Wales; the British population was estimated at about 10,000 pairs in 1999 (Baker et al 2002).

In winter it is predominantly a bird of coastal fields and saltmarshes, being commonest in Scotland and northern England. In eastern England, where numbers are declining, The Wash and the Essex marshes form its main wintering areas (Lack 1986), involving birds that move south-east from the Pennines (Baker et al 2002). In southern England and most of Wales Twite is extraordinarily rare, and sightings away from the east coast should be treated with great caution. It has always been rare on the south-west peninsula and, since the early 1990s, it has declined significantly along the English south coast, illustrated by the fact that none were seen in Dorset in 2000 and 2003, the first blank years since 1974 (Green 2004).

As a final point of interest on its distribution, Twite has a very peculiar world range. The race pipilans breeds in Britain and Ireland, whereas the nominate flavirostris breeds in Norway, creeping into northern Sweden and the extreme north-west of Russia. The nearest population to that is in the Caucasus, eastern Turkey and north-western Iran (race brevisrostris). It then occurs across Central Asia and the Himalayas. This curious distribution is presumably due to fragmentation of its range during the last ice age, about 18,000-20,000 years ago (Gibbons et al 1993).

Linnet in fresh winter plumage

The familiar and widespread Linnet is the yardstick when identifying Twite. It is a small, rather dumpy finch, usually located by its dry, twittering calls. These sound conversational in a flock, but are difficult to transcribe individually: a quick but subdued dib dib di-di-dip is about the closest I could get in a recent encounter.

In late autumn and winter Linnets are rather nondescript buffy birds. The rich buff underparts and the darker browny buff upperparts are profusely streaked with grey-brown, but this is subdued and rather diffuse. The head is greyer, with a pattern that is also rather subdued, making the bird look quite plain-headed from a distance. At closer range, the forehead and the supercilium are a rich buff in colour. The latter is most prominent immediately above the eye and, together with a buff crescent below the eye (the ‘sub-ocular crescent’) it forms a large but diffuse eyering. There is also a buff spot in the centre of the ear coverts. The sides of the throat are rich buff too, but dark streaking obscures the centre of the throat.

Buff tips to the greater coverts form only a slight wing-bar. The sexes are similar in winter but close scrutiny reveals that adult males are more colour-saturated, being slightly chestnut-toned above and a somewhat deeper buff below. The bill is grey and the legs are dark reddish.

Most distinctive are the prominent white fringes to the outer webs of the basal and middle parts of the otherwise black primaries, and these form a white panel at rest. The black tail also has prominent white fringes to the outer webs of all but the central feathers. As a consequence, both the primaries and the tail show prominent white basal ‘flashes’ in flight. The uppertail coverts are paler and buffer, and not particularly striking in flight.

Twite

In winter Twite is superficially similar to Linnet, but is slightly slimmer and has a distinctly longer tail (about 10 per cent longer; Cramp 1994) with a deeper fork. It too has obvious white flashes in the primaries and tail, but three other features readily separate it:

  • A distinctive and rather beautiful orange-buff ground colour to the face and the unstreaked throat. Brown streaking extends from the sides of the breast rather diffusely down onto the flanks, but the belly and undertail coverts are white.
  • Darker brown upperparts with darker streaks, and a more prominent wingbar, varying from buff to whitish, across the tips of the greater coverts. The upperparts are thus more similar to those of Lesser Redpoll than those of Linnet.
  • An obviously yellow bill in winter, contrasting with the face. In summer the bill is grey (it normally starts to darken in March-April; Cramp 1994).

The male’s pink rump is often partially obscured by pale feather fringes in autumn and winter, and although it is brighter in summer it can still be frustratingly difficult to see, even in flight. The female’s rump is brown, streaked black. Like Linnet, Twite has a variety of calls, including twittering noises that hardly differ from Linnet’s except that they are usually slightly harder and more nasal, and softer calls, such as a quiet tweep tweep tweep. Most distinctive, and useful for locating a Twite among a flock of Linnets, is a harsh, disyllabic nasal tchooik.

Plumage wear

Linnets have a complete post-breeding moult between June and October, so by early winter they are in fresh plumage with broad grey, brown or buff feather edgings. These gradually wear and by late winter have a colder tone and look somewhat duller. Male Linnet’s pretty summer plumage – grey head, chestnut back and bright pink forehead and breast – is acquired not by moult but by the gradual and continual wearing away of the brownish or greyish feather edges and tips.

Twite also has only one moult a year and both sexes gradually become darker and more worn by the breeding season. Unlike Linnet, the male does not acquire a distinctive summer plumage.