Fact-checked by Grok 2 weeks ago

Twite

The twite (Linaria flavirostris) is a small, brown passerine bird in the finch family Fringillidae, measuring about 14 cm in length and closely related to the linnet but distinguished by its stubbier bill, shorter tail, tawny back heavily streaked with dark brown, pale yellow bill, and—in males—a conspicuous pink rump.^[1]^[2] This species exhibits limited sexual dimorphism, with females showing buff tones instead of pink on the rump, and both sexes displaying warm buffy underparts and streaky brownish upperparts that provide camouflage in their preferred open habitats.^[3]^[4] Twites are primarily seed-eaters, foraging on the ground in flocks during winter, and they breed in loose colonies where nests are built in heather or gorse, lined with feathers and hair.^[1]^[2] Twites have a disjunct distribution, breeding mainly in northern Europe—particularly upland moors, barren hillsides, and coastal grasslands in the UK (especially Scotland and northern England), Ireland, Scandinavia, and Iceland—and in montane regions of Asia from eastern Turkey to the Himalayas, Kamchatka, and northern China.^[5]^[2] They are partially migratory, with northern populations wintering in lowland weedy fields, saltmarshes, and coastal areas across Europe and into the Middle East, though some remain resident in milder regions.^[5]^[4] Globally classified as Least Concern by the IUCN, twites face regional declines due to agricultural intensification, habitat loss from overgrazing, and climate change impacts on breeding grounds, leading to a "Red" conservation status in the UK where populations have decreased by over 50% since the 1970s.^[5]^[1] Conservation efforts focus on restoring upland meadows and coastal habitats to support their seed-based diet.^[2]^[6]

Taxonomy and systematics

Etymology and classification

The Twite was first described scientifically by Carl Linnaeus in 1758 as Fringilla flavirostris in the 10th edition of Systema Naturae.^[7] The species epithet flavirostris derives from Latin, combining flavus (yellow) and rostrum (beak), referring to the bird's distinctive yellow bill.^[8] The genus name Linaria, adopted in modern taxonomy, originates from Latin linum (flax), alluding to the historical association of these finches with flax seeds, which they consume, and the term's earlier use for linen-weavers in reference to their feeding habits. Historically, the Twite was classified under the genus Carduelis, as Carduelis flavirostris, following its initial placement in Fringilla.^[7] This changed in 2012 when phylogenetic analysis of mitochondrial and nuclear DNA sequences demonstrated that the Twite and the Eurasian linnet (Linaria cannabina) form a distinct clade more closely related to each other than to other Carduelis species, warranting separation into the genus Linaria. The study, based on multi-locus data from 93 taxa representing 205 finch species, resolved generic limits within Fringillidae and supported Linaria as a monophyletic group. The Twite is placed in the family Fringillidae, the true finches, and specifically within the subfamily Carduelinae, which encompasses most seed-eating finches with conical bills adapted for granivory.^[7] This subfamily classification reflects the Twite's evolutionary affinities to other cardueline finches, confirmed by the same DNA-based phylogeny that highlighted its close ties to the Eurasian linnet.

Subspecies

The Twite (Linaria flavirostris) is divided into nine subspecies, as recognized by authorities including the Handbook of the Birds of the World (HBW) and BirdLife International.^[9]^[5] These subspecies are primarily distinguished by variations in plumage coloration and pattern, bill size and shape, and subtle differences in vocalizations, reflecting adaptations to diverse habitats across their Palearctic range.^[9] The nominate subspecies, L. f. flavirostris, breeds from Scandinavia to northern Russia (including Norway, northern Sweden, northern Finland, and the Kola Peninsula) and winters southward to central and eastern Europe along Baltic and North Sea coasts.^[9] It represents the standard form, with typical brownish-streaked plumage and a stubby yellow bill in winter. In Britain and Ireland, L. f. pipilans is found, breeding in northern regions and wintering along coastal areas to southeastern England and the Netherlands; males exhibit pinker rumps than in the nominate form.^[9] L. f. brevirostris breeds in the Caucasus, eastern Turkey, and northern Iran, with a notably smaller bill compared to other subspecies.^[9] Asian mountain populations include L. f. rufostrigata in the Himalayas, Ladakh, western and southern Tibetan Plateau, northern India, and Nepal, featuring rufous tones in the plumage; and L. f. altaica in the Altai Mountains, Tuva Republic, and western/northern Mongolia, characterized by paler overall plumage.^[9] The remaining subspecies are L. f. kirghizorum (northern and central Kazakhstan), L. f. korejevi (southern Ural Mountains to Caspian Sea, Kirghiz steppes, and Tien Shan), L. f. montanella (eastern Kyrgyzstan, Pamir-Alai Mountains, Tajikistan, southern Uzbekistan, western-central China, Afghanistan, and northern Pakistan), and L. f. miniakensis (eastern Tibetan Plateau to central China, including southern Qinghai, eastern Tibet, Gansu, and western Sichuan). These forms show clinal variations in streaking intensity and buff tones, with bill color shifting seasonally from grayish in breeding plumage to yellowish in winter across all subspecies.^[9]

Physical characteristics

Plumage and morphology

The Twite (Linaria flavirostris) is a small finch measuring 13–14 cm in length, with a wingspan of 21–23 cm and a body mass of 13–18 g.^[10]^[11] It possesses a stout, conical bill, dark gray during the breeding season and yellowish in the non-breeding winter plumage.^[3]^[10] The legs are dark brown, and the eyes feature dark irises.^[12]^[13] The tail is slightly forked, dark brown with white outer edges, and relatively longer than that of the similar common linnet.^[1]^[10] The plumage is overall brownish and streaky, providing camouflage in upland habitats, with upperparts featuring olive-brown feathers edged paler and streaked darker.^[10]^[1] Underparts are buff to pale whitish with fine dark streaks on the breast, flanks, and undertail coverts, while the head shows a buffish-brown ear patch and cheek lightly streaked.^[10]^[12] The wings are dark brown with prominent pale wing bars formed by whitish edges on the greater coverts and tips of the secondaries and inner primaries.^[10] In non-breeding plumage, the overall tones are warmer and more buffy, with less distinct streaking.^[3] Sexual dimorphism is limited but evident in breeding adults, where males display a bright pink rump contrasting with the streaked back, along with slightly brighter buff underparts and more pronounced pale edges on the upperparts.^[1]^[10] Females lack the pink rump, instead showing dull brown, and appear more cryptic overall with subdued streaking and tones; immatures resemble adult females but with even buffer underparts and finer streaking.^[1]^[10] Subspecies exhibit minor variations in plumage saturation and size, with paler tones in some Asian forms.^[12]

Vocalizations

The Twite produces a distinctive primary call described as a nasal "twite," "twaa-it," or "twy-eet," which is frequently used during flight and for contact between individuals.^[14]^[6]^[15] This call serves to maintain communication within flocks, particularly when birds are foraging or moving together.^[15] The song of the Twite is a rapid, twittering series of metallic and buzzing notes, often incorporating fast trills and twitters, and is similar to that of the common linnet (Linaria cannabina) but generally less musical.^[12]^[16]^[17] Males deliver the song from a perch or in undulating flight, with more complex variations during the breeding period to aid in territory defense and mate attraction.^[16]^[15] Alarm calls consist of sharp "tsik" or similar abrupt notes, emitted in response to potential threats.^[18] Immature Twites produce a subsong, which is a quieter, less structured version of the adult song.^[18]

Distribution and habitat

Breeding range

The Twite (Linaria flavirostris) has a disjunct breeding distribution spanning northern Europe and Asia. In Europe, it primarily breeds in upland regions of the United Kingdom, including the Scottish Highlands and northern England, as well as coastal areas of Ireland, the Faroe Islands, and Scandinavia (notably Norway, Sweden, and Finland).^[2]^[5]^[19] These populations favor upland moors, coastal heaths, and moorland fringes at elevations typically from sea level in coastal areas to over 1,000 m in inland uplands, where open terrain supports nesting and foraging.^[19]^[2]^[12] Within these European breeding grounds, the species occupies dwarf shrub heaths and moorlands characterized by heather (Calluna vulgaris) and bracken (Pteridium aquilinum), often near boggy areas or scree slopes with sparse, seed-rich vegetation essential for adult diet and insect availability for nestlings.^[5] The breeding season in Europe runs from May to July, aligning with peak vegetation growth and insect abundance.^[2] In Asia, breeding occurs discontinuously from eastern Turkey and the Caucasus, through Central Asian mountains and the Himalayas, to northern China, Mongolia, and Siberia.^[20]^[12] Asian populations inhabit high-altitude grasslands, steppes, and alpine meadows up to 4,900 m, particularly in the Himalayas where elevations reach 3,500–4,900 m.^[12]^[16] Habitats consist of barren hillsides, boulder-strewn plateaux, and submontane areas with dwarf shrubs and grassy tussocks that provide seeds and insects.^[5] Breeding timing varies with altitude, starting later (up to August) at higher elevations compared to lower sites.^[5]

Non-breeding range and migration

The Twite (Linaria flavirostris) is a partial migrant, with northern European populations typically relocating southward or to coastal areas during the non-breeding season, while Asian populations descend to lower elevations from their montane breeding grounds.^[12]^[5] In Europe, the subspecies L. f. pipilans, which breeds in northern Britain and Ireland, winters primarily along the southerly coasts of the UK and Ireland, including sites such as the southeast coasts of England and Flintshire marshes in Wales.^[2]^[21] The nominate subspecies L. f. flavirostris from Scandinavia and northern Russia moves to wintering grounds along the Baltic and North Sea coasts, extending into central and eastern Europe.^[12] Migration in the Twite is generally short-distance and irregular, with birds forming flocks in autumn as they depart breeding areas between October and November.^[2]^[21] In the UK, the non-breeding population is supplemented by immigrants from Scandinavia, contributing to variable winter abundances at coastal sites.^[2] Asian subspecies, such as L. f. montanella and L. f. altaica, undertake elevational migrations to lowland areas in countries including China, Kazakhstan, and Mongolia, though specific routes remain less documented.^[12]^[5] Outside the breeding season, Twite shift habitats from upland moors to lowland weedy fields, estuaries, coastal dunes, and saltmarshes, where they access abundant seeds.^[2]^[21] In western Europe, wintering birds favor open coastal fringes and tidelines rich in small seeds, with some individuals remaining near breeding sites if local farmland provides sufficient weed resources.^[2]^[21] Flocking behavior intensifies during these movements, aiding foraging efficiency in non-breeding habitats.^[2]

Ecology and behavior

Diet and foraging

The Twite primarily feeds on seeds from grasses, heather (Calluna), dock (Rumex), and various composites such as dandelions (Taraxacum) and thistles (Cirsium). Buds from plants like juniper (Juniperus), birch (Betula), bilberry (Vaccinium), and crowberry (Empetrum) also form part of its diet. These seed sources are gleaned from moorland, grassland, and coastal habitats, supporting the bird's year-round nutritional needs.^[12]^[5] In addition to seeds, the Twite consumes small numbers of invertebrates, including beetles (Coleoptera) and flies (Diptera), with intake increasing during the summer months to provide essential protein. Specific examples include larvae and aphids taken opportunistically from vegetation. This dietary supplement is particularly relevant outside the strict breeding context, enhancing overall foraging efficiency in protein-scarce environments.^[12]^[15] Foraging occurs mainly on the ground or within low vegetation, where the Twite uses its conical bill to extract and husk seeds without specialized tools. In winter, it forms flocks typically numbering 20–100 birds, enabling efficient exploitation of weed seeds in saltmarsh, farmland edges, or stubbles, such as those from annual meadow grass (Poa annua), chickweed (Stellaria media), and fat hen (Chenopodium album). These flocks reduce individual predation risk while targeting abundant, seasonal resources.^[12]^[21]^[20] The Twite competes with sympatric finches, such as linnets (Linaria cannabina), for shared seed resources in overlapping habitats, relying on its bill morphology for husking rather than probing deeply into soil. Seasonal shifts emphasize seeds in winter for energy conservation, while summer foraging incorporates more diverse low-level gleaning in flower-rich meadows and verges.^[5]^[22]

Reproduction

The Twite forms monogamous pairs during the breeding season, which typically spans from April to August. Males attract females through courtship displays, including song flights where they perform short circular or zigzag patterns at low heights while singing a twittering series of notes, prominently flashing their pink rump to emphasize it. These displays may also involve parabolic flights upward followed by stiff-winged descents to the ground, and males occasionally hop in front of perched females.^[23]^[15]^[24] Nests are constructed as compact, deep cup structures primarily from plant fibers, roots, heather, bracken, grass, moss, and animal hair, with an inner lining of feathers for insulation. The female builds the nest, often with some male assistance, and sites it on the ground or low in vegetation such as dwarf willow, heather, bilberry, bracken, rushes, or grass tussocks, rarely exceeding 1–3 m in height.^[5]^[23]^[14] Clutches consist of 3–6 pale blue to dark blue eggs, marked with reddish or purple-brown spots, scrawls, or blotches. Incubation lasts 12–13 days and is performed solely by the female, who is provisioned with food by the male during this period.^[5]^[23]^[15] Upon hatching, chicks are altricial and brooded by the female, with both parents actively feeding them primarily seeds, supplemented with some insects, transitioning to more seeds as the young develop. Chicks fledge after 11–15 days, remaining dependent on the parents for further provisioning. Pairs typically raise 1–2 broods per season, with laying dates often aligned to peak food availability from late May to mid-August.^[14]^[23]^[15] Breeding success is generally low, primarily due to high predation rates on nests and juveniles, with juvenile survival estimated at 0.14–0.31 in monitored UK populations, compared to 0.28–0.51 for adults. Nest survival from egg-laying to fledging can reach 77% in favorable habitats like crofting landscapes, but overall productivity is limited. Breeding densities vary regionally, ranging from 0.7–7.8 pairs/km² in the UK, with higher concentrations in northern England and the Western Isles.^[25]^[26]^[23]

Conservation

Population trends

The global population of the Twite (Linaria flavirostris) is estimated at 1.6–5.5 million mature individuals (2018 estimate), based on assessments of its extensive breeding range across northern Europe and central Asia.^[5] The population is not believed to be undergoing a significant decline at a global scale (trend unknown), as it does not approach thresholds for Vulnerable under IUCN criteria, though regional variations exist with some localized decreases.^[5] In the UK and Ireland, the Twite has undergone sharp declines since the 1990s, with the UK breeding population contracting by approximately 21% between 1999 (around 10,000 pairs) and 2013 (7,831 pairs, 95% confidence interval: 5,829–10,137), and even steeper losses of 72% in England alone during this period. Since 2013, declines have continued, with only 12 pairs breeding in England in 2021, placing the species on the brink of extinction there.^[20]^[27]^[28] The species has been Red-listed in the UK since 1996 due to these reductions in breeding numbers and range, particularly in upland areas.^[2] Ireland's breeding population is now critically low, estimated at 54–110 pairs (fewer than 500 overall; recent estimates suggest around 100 pairs as of 2023), confined mainly to coastal bogs in counties Mayo and Donegal.^[6] European populations outside the British Isles are not known to be declining significantly (trend unknown as of 2021), with the bulk of breeders (up to 274,000 pairs) concentrated in Scandinavia, especially Norway.^[5] In Asia, the species holds steady across its montane breeding grounds from Kazakhstan to Mongolia and China, contributing the majority to the global total.^[5] Vagrant records occur sporadically in North America and other distant regions, such as eastern Canada and the United States.^[12] UK monitoring through British Trust for Ornithology (BTO) surveys has been instrumental in tracking these trends, revealing consistent upland breeding losses via repeat national censuses in 1999 and 2013, alongside ongoing data from breeding bird atlases and ringing programs.^[2]

Threats and management

The Twite faces several key threats primarily related to habitat loss and degradation. Agricultural intensification, including overgrazing by livestock and the conversion of hay meadows to improved pasture, has significantly reduced seed-rich foraging habitats essential for breeding adults and chicks.^[2]^[27] Poor burning practices on moorlands further limit the availability of tall heather for nesting, forcing birds to use more exposed bracken sites.^[27] Climate change exacerbates these issues by altering upland vegetation patterns and reducing food availability, particularly at the southern edges of the species' range in Europe.^[27] Regionally, threats vary; in coastal wintering areas such as the Wadden Sea, large-scale embankments and increased grazing pressure degrade saltmarsh habitats.^[5] In Ireland, changes in land use and overgrazing similarly impact breeding sites.^[5] Predation pressure increases in altered habitats, with nest losses to mammalian predators like stoats and weasels when heather cover is insufficient.^[27] Globally, the Twite is classified as Least Concern by the IUCN due to its large range and population size, estimated at 1.6–5.5 million mature individuals (2018 estimate), though trends are uncertain.^[5] However, it is nationally vulnerable, holding Red List status in the UK since 1996 and Ireland due to steep regional declines in breeding numbers.^[2]^[5] Conservation management focuses on habitat restoration and monitoring. Agri-environment schemes, such as the UK's Environmental Land Management schemes and Ireland's Agri-Environment Options Scheme, support the creation of heather mosaics, late-cut hay meadows, and seed-rich field margins to enhance breeding and foraging opportunities.^[21] Sensitive grazing regimes—rotational and low-intensity—and controlled burning maintain diverse vegetation structure on moorlands.^[21] Monitoring programs led by the British Trust for Ornithology (BTO) and Royal Society for the Protection of Birds (RSPB), including national surveys and color-ringing efforts, track population dynamics and inform targeted interventions.^[20]^[28] No specific international agreements target the Twite, but it benefits from broader protections under the Bern Convention Appendix II.^[5]

References

[1]
Twite Bird Facts | Carduelis Flavirostris - RSPB
The Twite is a small, brown finch closely related to the Linnet, but with a shorter tail and stubbier beak. Its back is tawny, heavily streaked with dark brown.
[2]
Twite - BTO
This small, brown finch with a yellow bill and pink rump is very much a bird of coastal fringes and higher ground. There is little colouration difference ...
[3]
Twite - eBird
Stout little streaky brownish finch of open, often barren spaces. Easily overlooked. Note warm buffy tones (especially in autumn–winter) and pale bill.
[4]
Twite | The Wildlife Trusts
Twite are small finches, about the size and shape of a linnet. They have a very short, stubby beak. They're brown on the back with darker streaking, and paler ...
[5]
Twite Linaria Flavirostris Species Factsheet | BirdLife DataZone
This species breeds on lower montane and submontane plateaux, open moorland, barren hillsides, scree slopes, boulder-strewn areas with little or sparse ...
[6]
Twite - BirdWatch Ireland
The Twite is a declining breeding species mainly on the north and west coast of Ireland and a scarce winter visitor to north-eastern coasts.
[7]
Linaria flavirostris (Twite) - Avibase
Original description. Citation: (Linnaeus, C 1758). Reference: Systema Naturae ed. 10 1 p.182. Protonym: Fringilla flavirostris.
[8]
flavirostris - Wiktionary, the free dictionary
From flāvus (“yellow, flaxen, golden”) + rōstrum (“beak, snout”). Adjective. flāvirōstris (neuter flāvirōstre); third-declension two-termination adjective.Missing: billed | Show results with:billed
[9]
https://birdsoftheworld.org/bow/species/twite1/cur/systematics
[10]
Twite | Identification Guide - Bird Spot
Out of breeding season twites are paler and the feather pattern is less distinctive, and the bill turns yellow. Females are similar to males but lack the pink ...Missing: differences | Show results with:differences
[11]
Twite Facts: Identification, Diet, Migration Info etc. - Binocular Base
Length: 14cm. Wingspan: 22-24cm. Weight: 13-18g. Scientific Name: Linaria flavirostris. The Twite Can Be Seen In The UK During The Following Months. January ...
[12]
Twite - Linaria flavirostris - Birds of the World
Mar 4, 2020 · Breeding densities of 5–7·8 pairs/km2 in N England and 0·7·4·3 pairs/km2 in W Norway. British Is breeding population decreased since 1970 most ...
[13]
Twite, Linaria flavirostris - Birds - NatureGate - LuontoPortti
Appearance. A medium-sized brownish finch. · Size. Length 12.5–14 cm, weight 14–18 g. · Nest. On the ground or rocks, sometimes in a bush, well concealed.Missing: wingspan | Show results with:wingspan
[14]
TWITE (Linaria flavirostris) - songbird factfile
The twite is a small brown finch about the size and shape of a linnet. They have brown backs with lots of lighter brown and dark streaking. They have a pale ...
[15]
Twite Bird Facts (Linaria flavirostris) | Birdfact
Beaks and Skulls Eyes and Vision Wings and Flight Legs and Feet ... Leg Colour. Black. Primary Colour (Female). Brown Buff. Secondary Colour (Female).
[16]
Twite - Linaria flavirostris - Oiseaux.net
Oct 28, 2023 · It has become uniform because the stripes have faded a little. The bill has darkened, it has become grey on top with the base of the mandible ...Missing: differences | Show results with:differences
[17]
Twite - Facts, Diet, Habitat & Pictures on Animalia.bio
The call is a distinctive twit, from which its name derives, and the song contains fast trills and twitters. Twites can form large flocks outside the breeding ...Photos With Twite · Biome · Habits And Lifestyle
[18]
Twite · Linaria flavirostris · (Linnaeus, 1758) - Xeno-Canto
call, flight call, song. Parabola placed on ground under feeder,… more ». Parabola placed on ground under feeder, birds perched in trees above. « less. [sono] ...
[19]
Twite Conservation - Advice for Farmers - RSPB
The twite breeds on moorland fringes in the upland areas of Northern England and Scotland.
[20]
The population status of breeding Twite Linaria flavirostris in the UK ...
Jun 24, 2018 · The Twite Linaria flavirostris is a small seed-eating finch (Fringillidae) of open habitats, with a world range consisting of two widely ...
[21]
[PDF] TWITE (Linaria flavirostris) - Species On The Edge
In winter, most birds move to coastal areas where they feed on saltmarsh or low-lying farmland rich in weed seeds, while others remain on farmland near breeding ...
[22]
Breeding ecology of Twite Carduelis flavirostris in a crofting landscape
Twite Carduelis flavirostris are small, seed‐eating finches (Fringillidae). Their world distribution consists of two widely separated populations, ...
[23]
https://doi.org/10.2173/bow.twite1.01
[24]
[PDF] 2023 Twite Breeding Survey in Ogwen Valley - Eryri National Park
Display flight – Males show off pink rump, show flight into air, parachute down to ground with stiff wings. Males will display to other females, not just the ...<|separator|>
[25]
Young Twite suffer high mortality - BirdGuides
Mar 22, 2023 · Young birds suffered higher mortality with less than a third surviving their first year, even at the optimistic end of the calculations.Missing: densities | Show results with:densities
[26]
Breeding ecology of Twite Carduelis flavirostris in a crofting landscape
The nest survival rate from first‐egg to fledging was 77 ... Twite in the Western Isles breed relatively successfully and at high density in a UK context.
[27]
Twite – or 'Pennine finch' – on brink of extinction in England | Birds
Nov 6, 2021 · Reasons for the bird's disappearance include less wild seed in upland meadows, climate change and the loss of tall heather in uplands, resulting ...
[28]
Twite on brink of extirpation in England - BirdGuides
Nov 11, 2021 · Twite has suffered a steep decline this century, with the breeding population falling by 75% between 1999 and 2013.Missing: 50% 1990s