Red crossbill

The red crossbill (Loxia curvirostra) is a small passerine bird in the finch family Fringillidae, also known as the common crossbill in Eurasia. Crossbills have distinctive mandibles, crossed at the tips, which enable them to extract seeds from conifer cones and other fruits.

Adults are often brightly coloured, with red or orange males and green or yellow females, but there is wide variation in colour, beak size and shape, and call types, leading to different classifications of variants, some of which have been named as subspecies.

Red crossbill
Red Crossbills (Male)
Male red crossbill
Red Crossbill (Female)
Female red crossbill
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Fringillidae
Subfamily: Carduelinae
Genus: Loxia
Species:
L. curvirostra
Binomial name
Loxia curvirostra

Description

Crossbills are characterized by the mandibles crossing at their tips, which gives the group its English name. Using their crossed mandibles for leverage, crossbills are able to efficiently separate the scales of conifer cones and extract the seeds on which they feed. Adult males tend to be red or orange in colour, and females green or yellow, but there is much variation.

In North America, nine distinct red crossbill variants (referred to as call types) differing in vocalizations as well as beak size and shape are recognized.[2] Each call type evolved to specialize on different species of conifer.[3]

Breeding and irruption

Loxia curvirostra poliogyna MHNT.ZOO.2010.11.220 Tébessa
Eggs from the collections of the MHNT

The red crossbill breeds in the spruce forests of North America, as well as Europe and Asia. Some populations breed in pine forests in certain areas of all three continents, and in North America, also in Douglas-fir. It nests in conifers, laying 3–5 eggs.

Matthew Paris 1251 sketch of Crossbill eating fruit
Mediaeval sketch by Matthew Paris in his Chronica Majora (1254) of a crossbill holding a fruit in its beak, with the Latin words Alaudis parum majores ('a little bigger than larks').

This crossbill is mainly resident, but often irrupts south when its food source fails. These irruptions led in the twentieth century to the establishment of permanent breeding colonies in England, and more recently in Ireland. This species forms flocks outside the breeding season, often mixed with other crossbills.

The first known irruption, recorded in England by the chronicler Matthew Paris, was in 1254; the next, also in England, appears to have been in 1593 (by which time the earlier irruption had apparently been entirely forgotten, since the crossbills were described as "unknown" in England).[4] The engraver Thomas Bewick wrote that "It sometimes is met with in great numbers in this country, but its visits are not regular",[5] adding that many hundreds arrived in 1821. Bewick then cites Matthew Paris as writing "In 1254, in the fruit season, certain wonderful birds, which had never before been seen in England, appeared, chiefly in the orchards. They were a little bigger than Larks, and eat the pippins of the apples [pomorum grana] but no other part of them... They had the parts of the beak crossed [cancellatas] by which they divided the apples as with a forceps or knife. The parts of the apples which they left were as if they had been infected with poison."[5] Bewick further records an account by Sir Roger Twysden for the Additions to the Additamenta of Matt. Paris "that in the apple season of 1593, an immense multitude of unknown birds came into England ... swallowing nothing but the pippins, [granella ipsa sive acinos] and for the purpose of dividing the apple, their beaks were admirably adapted by nature, for they turn back, and strike one point upon the other, so as to show ... the transverse sickles, one turned past the other."[5]

Taxonomy and systematics

Crossbill woodcut by Thomas Bewick
'The Cross-Bill' wood engraving in Thomas Bewick's A History of British Birds (1847 edition)

The genus name Loxia is from Ancient Greek loxos, "crosswise", and curvirostra is Latin for curved bill".[6]

This species is difficult to separate from parrot crossbill and Scottish crossbill, both of which breed within its Eurasian range, as plumage distinctions from those two species are negligible, though the head and bill are smaller than in either of the other species. Care is needed in identification, especially in Eurasia, where the glip or chup call is probably the best indicator. The identification problem is less severe in North America, where only red crossbill and White-winged crossbill occur. However, there has been debate as to whether different call types should be considered separate species. For example, the South Hills crossbill, occurring in the South Hills and Albion Mountains in Idaho has been described as a new species (Loxia sinesciuris) because it shows a very low degree of hybridization with the red crossbill.[7] There are also genetic differences between the call type populations.[8] Nevertheless, few ornithologists have chosen to give these forms species status.

Some large-billed, pine-feeding populations currently assigned to this species in the Mediterranean area may possibly be better referred to either parrot crossbill or to new species in their own right, but more research is needed. These include Balearic crossbill L. curvirostra balearica and North African crossbill L. curvirostra poliogyna, feeding primarily on Aleppo pine (Pinus halepensis); Cyprus crossbill L. curvirostra guillemardi, feeding primarily on European black pine (Pinus nigra); and an as-yet unidentified crossbill with a parrot crossbill-size bill feeding primarily on Bosnian pine (Pinus heldreichii) in the Balkans. These populations also differ on plumage, with the Balearic, North African and Cyprus races having yellower males, and the Balkan type having deep purple-pink males; this however merely reflects the differing anthocyanin content of the cones they feed on, as these pigments are transferred to the feathers.

Diversity

Crossbill skull and jaw anatomy from Yarrell History of British Birds 1843 (detail)
Crossbill skull and jaw anatomy from William Yarrell's A History of British Birds (1843)
Loxia curvirostra NA map
Distribution in North America.
  Year-round
  Year-round (scarce)
  Nonbreeding
  Nonbreeding (scarce)
Correlations between different classifications of Eurasian crossbills
Distinct Eurasian common crossbill
populations
Associated
tree species
Summers' list
based on calls
The Sound Approach's
list based on calls[9]
Call-Type,
Flight Call
Balearic crossbill, Loxia curvirostra balearica Aleppo pine, Pinus halepensis
North African crossbill, Loxia c. poliogyna Aleppo pine, Pinus halepensis 3E
Corsican crossbill, Loxia c. corsicana European black pine, Pinus nigra
Cyprus, Turkey + Caucases crossbill, Loxia c. guillemardi European black pine, Pinus nigra 5D
Crimean crossbill, Loxia c. mariae European black pine, Pinus nigra?
Luzon crossbill, Loxia c. luzoniensis Khasi pine, Pinus kesiya
Annam crossbill, Loxia c. meridionalis Khasi pine, Pinus kesiya
Altai crossbill, Loxia c. altaiensis Spruces
Tien Shan crossbill, Loxia c. tianschanica Schrenk's spruce, Picea schrenkiana
Himalayan crossbill, Loxia c. himalayensis Himalayan hemlock, Tsuga dumosa
Japanese crossbill, Loxia c. japonica
Other Eurasian crossbills
1A 'British crossbill' Type E - flight call "Chip"
1B 'Parakeet crossbill' Type X - flight call "Cheep"
2B 'Wandering crossbill' Type A - flight call "Keep"
Parrot crossbill, Loxia ptyopsittacus Scots pine 2D
Scottish crossbill, Loxia scotica Scots pine, Larch, Lodgepole pine 3C
'Bohemian crossbill' Type B - flight call "Weet"
4E 'Glip crossbill' Type C - flight call "Glip"
'Phantom crossbill' Type D - flight call "Jip"
'Scarce crossbill' Type F - flight call "Trip"
Loxia c. percna
Newfoundland crossbill, Loxia c. percna
Correlations between different classifications of North American crossbills
North American red crossbill subspecies based on biometrics Jeff Groth's list
using call-types
Recorded on tree species
(Jeff Groth call types)
Newfoundland crossbill, Loxia c. percna Type 8 Black spruce, Picea mariana
Lesser crossbill, Loxia c. minor Type 3 Western hemlock, Tsuga heterophylla
Sitka crossbill, Loxia c. sitkensis (probably a junior synonym of L. c. minor) Type 3 ditto
Loxia c. neogaea Type 1 Tsuga species, Picea glauca, Pinus strobus
Loxia c. neogaea Type 4 Douglas fir, Pseudotsuga menziesii
Rocky Mountain crossbill, Loxia c. benti Types 2, 7 Type 2: Rocky Mountains Ponderosa pine Pinus ponderosa scopulorum in west, various Pinus species in east; Type 7: possibly a general diet
Sierra crossbill, Loxia c. grinnelli Type 2, 7 ditto
Bendire crossbill, Loxia c. bendirei Type 2, 7 ditto
Mexican crossbill, Loxia c. stricklandi Type 6 Pine species in section Trifoliae
Central American crossbill, Loxia c. mesamericana
South Hills crossbill (described as Loxia sinesciuris in 2009)[7] Type 9 Isolated population of Lodgepole Pine, Pinus contorta latifolia

References

  1. ^ BirdLife International (2012). "Loxia curvirostra". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
  2. ^ Benkman, C. W.; Parchman, T. L.; E. Mezquida (2010). "Patterns of coevolution in the adaptive radiation of crossbills". Annals of the New York Academy of Sciences. 1206: 1–16. doi:10.1111/j.1749-6632.2010.05702.x. PMID 20860680.
  3. ^ Benkman, C. W. (2003). "Divergent selection drives the adaptive radiation of crossbills". Evolution. 57 (5): 1176. doi:10.1554/0014-3820(2003)057[1176:dsdtar]2.0.co;2.
  4. ^ Perry, Richard Wildlife in Britain and Ireland Croom Helm Ltd. London 1978 pp. 134–5.
  5. ^ a b c Bewick, Thomas (1847). A History of British Birds, volume I, Land Birds (revised ed.). pp. 234–235.. Roger Twysden's Latin note on the 1593 outbreak is given in William Wats's edition of Paris's Chronica Majora (London, 1640).
  6. ^ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London, United Kingdom: Christopher Helm. pp. 125, 231. ISBN 978-1-4081-2501-4.
  7. ^ a b Benkman, Craig W.; Smith, Julie W.; Keenan, Patrick C.; Parchman, Thomas L.; Santisteban, Leonard (2009). "A New Species of the Red Crossbill (Fringillidae: Loxia) From Idaho". The Condor. 111 (1): 169–176. doi:10.1525/cond.2009.080042.
  8. ^ Parchman, T. L.; C. W. Benkman (2006). "Patterns of genetic variation in the adaptive radiation of New World crossbills (Aves: Loxia)". Molecular Ecology. 15: 1873–1887. doi:10.1111/j.1365-294x.2006.02895.x. PMID 16689904.
  9. ^ Magnus S Robb: Introduction to vocalizations of crossbills in north-western Europe

External links

Cassia crossbill

The Cassia crossbill (Loxia sinesciuris) is a passerine bird in the family Fringillidae. It is endemic to the South Hills and Albion Mountains in southern Idaho. Cassia crossbill rarely interbreeds with other call types that move into the South Hills of Idaho yearly, and can be considered to represent a distinct species via ecological speciation. The Cassia crossbill have specialized beaks to access the seeds of the lodgepole pine cones in this region but are poorly adapted to other pine cones in surrounding regions.The species was first described in 2009, but only was accepted to be its own species in 2017 when it was found out to be phylogenetically distinct from the red crossbill and its 10 unique call types.

Crossbill

The crossbill is a genus, Loxia, of birds in the finch family (Fringillidae), with six species. These birds are characterised by the mandibles with crossed tips, which gives the group its English name. Adult males tend to be red or orange in colour, and females green or yellow, but there is much variation.

Crossbills are specialist feeders on conifer cones, and the unusual bill shape is an adaptation which enables them to extract seeds from cones. These birds are typically found in higher northern hemisphere latitudes, where their food sources grow. They erupt out of the breeding range when the cone crop fails. Crossbills breed very early in the year, often in winter months, to take advantage of maximum cone supplies.

Fauna of Toronto

The fauna of Toronto include a variety of different species that have adapted to the urban environment, its parks, its ravine system, and the creeks and rivers that run throughout Toronto. Many other animals from outside the city limits have been known to straddle inside on from time to time.

Jebel ech Chambi

Jebel ech Chambi (Arabic: جبل الشعانبي‎; also spelled Mount Ash-Sha'nabi) is a mountain peak in Tunisia. It has an elevation of 1,544 m (5,066 ft), and is the highest mountain in the country. It stands above the city of Kasserine in western central Tunisia. The summit is covered by a pine forest and is part of Chambi National Park.

List of birds of Alberta

.

This is a list of bird species confirmed in the Canadian province of Alberta. Unless otherwise noted, the list is that of Bird Checklists of the World as of June 2019. Of the 435 species on the list, 129 are accidental and eight were introduced to North America. One species is extinct and another probably is.

Only birds that are considered to have established, self-sustaining, wild populations are included on this list. This means that birds that are considered probable escapees, although they may have been sighted flying free, are not included.

This list is presented in the taxonomic sequence of the Check-list of North and Middle American Birds, 7th edition through the 60th Supplement, published by the American Ornithological Society (AOS). Common and scientific names are also those of the Check-list except that Canadian English spelling is used.

The following tags are used to describe some categories of occurrence.

(A) Accidental - a species that rarely or accidentally occurs in Alberta

(I) Introduced - a species that has been introduced to Alberta by the actions of humans, either directly or indirectly

List of birds of the Klamath Basin

The following bird species are found in the Klamath Basin, Oregon, and related areas; (a few species listed are only "native" and have a larger continental range). The Klamath Basin is within the Pacific Flyway so, over 350 species can be spotted migrating through the flyover.

List of fauna of Michigan

This is a list of fauna found in the U.S. state of Michigan, including those of wider distribution. See also List of threatened fauna of Michigan.

List of fauna of Sequalitchew Creek

The following is a list of fauna of Sequalitchew Creek in the U.S. state of Washington categorized by type. Sequalitchew Creek is located in DuPont, Washington. It emanates from Sequalitchew Lake, Fort Lewis, Washington and was the location of the original Fort Nisqually trading post established in 1833 by the Hudson's Bay Company. Sequalitchew Creek runs from Sequalitchew Lake, through Edmonds Marsh, down the canyon and out to the Puget Sound.

Moghrar

Moghrar (Arabic: مغرار‎) is a municipality in Naâma Province, Algeria. It is the district seat the Moghrar District and has a population of 2,796, which gives it 11 seats in the PMA. Its municipal code is 4506

Two distinct oases are to be considered: Moghrar Foukani or higher Moghrar, on the Algerian National Highway number 6, the chief town; and Moghrar Tahtani or lower Moghrar located 15 km northeast of the first locality.

Mountain Lake Wilderness

Mountain Lake Wilderness is a U.S. Wilderness Area in the George Washington and Jefferson National Forests. The wilderness area is located next to privately owned Mountain Lake, and consists of 8,314 acres (3,365 ha) in Virginia and 2,721 acres (1,101 ha) in West Virginia.Thanks to frequent rains and a high elevation, the wilderness provides habitat not found in other areas of the southern Appalachians, habitats such as mountain bogs, vernal ponds and red spruce wetlands.The area is part of the Mountain Lake Wilderness Cluster.

Newfoundland crossbill

The Newfoundland red crossbill is a member of the crossbill genus which has its crossed bill adapted for prying open the tightly closed spruce or pine cones in order to extract the seeds found abundantly on the island of Newfoundland.

It is known locally as the spruce mope. About 5.5 to 6.5 inches in length, wing about 3.75 inches and its bill .70 inches. The adult male is a dull red which is somewhat brighter on the rump, with wings and tail black in color. The adult female is an olive-gray with yellow on the rump and often on the under parts, the wings and tail a dark grayish. Juveniles vary in color from olive-green to yellow to reddish.

They nest in conifers building their nest from twigs or strips of bark and lining it with mosses, hair or fur. They lay 4 to 5 eggs which are greenish-blue, spotted with brown and lavender.

The local name refers to their slow movements while feeding in the spruce tops. They can be seen in mixed company with the slightly larger white-winged crossbill.

Néouvielle National Nature Reserve

Néouvielle National Nature Reserve is a 2,313-hectare (5,720-acre) national nature reserve located in the Néouvielle massif. It ranges from 1,800 metres (5,900 ft) to 3,091 metres (10,141 ft). With a wide array of flora and fauna, it contains about 370 animal species and 570 breeds of algae.

Opportunistic breeder

Flexible or opportunistic breeders mate whenever the conditions of their environment become favorable. Their ability and motivation to mate are primarily independent of day-length (photoperiod) and instead rely on cues from short-term changes in local conditions like rainfall, food abundance and temperature. Another factor is the presence of suitable breeding sites, which may only form with heavy rain or other environmental changes.Thus, they are distinct from seasonal breeders that rely on changes in day length to induce entry into estrus and to cue mating, and continuous breeders like humans that can mate year-round. Other categories of breeders that perhaps can be subdivided under the heading "opportunistic" have been used to describe many species, such as many that are anurans like frogs. These include sporadic wet and sporadic dry, describing animals that breed sporadically not always under favorable conditions of rain or lack thereof.Many opportunistic breeders are non-mammals. Those that are mammals tend to be small rodents.Since changes in season can coincide with favorable changes in environment, the distinction between seasonal breeder and opportunistic can be muddled. In equatorial climes, the change in seasons is not always perceptible and thus, changes in day length not remarkable. Thus, the tree kangaroo (Dendrolagus) previously categorized as a seasonal breeder is now suspected to be an opportunistic breeder.Additionally, opportunists can have qualities of seasonal breeders. The red crossbill exhibits a preference (not a requirement) for long-day seasonality, but requires other factors, especially food abundance and social interactions, in order to breed. Conversely, food availability by itself incompletely promotes reproductive development.

Oregon Dunes National Recreation Area

The Oregon Dunes National Recreation Area is located on the Oregon Coast, stretching approximately 40 miles (64 km) north of the Coos River in North Bend to the Siuslaw River in Florence, and adjoining Honeyman State Park on the west. It is part of Siuslaw National Forest and is administered by the United States Forest Service.

The Oregon Dunes are a unique area of windswept sand. They are the largest expanse of coastal sand dunes in North America and one of the largest expanses of temperate coastal sand dunes in the world, with some dunes reaching 500 feet (150 m) above sea level. They are the product of millions of years of erosion by wind and rain on the Oregon Coast. The Oregon Dunes National Recreation Area provides numerous recreational activities, including off-highway vehicle (OHV) use, hiking, photography, fishing, canoeing, horseback riding, and camping. The Carter Dunes Trail and Oregon Dunes Day Use provide forest access for the disabled.

Frank Herbert's science-fiction novel Dune was inspired (in part) by the author's research and fascination with the area.

Parrot crossbill

The parrot crossbill (Loxia pytyopsittacus) is a small passerine bird in the finch family Fringillidae. The scientific name is from Ancient Greek. Loxia derives from loxos, "crosswise", and pytyopsittacus is from pitus, pituos, "pine", and psittakos, "parrot.

This bird breeds in the pine forests of northwest Europe and into western Russia. There is also a small population in Scotland, adding to the difficulty of distinguishing it from red crossbill and the endemic Scottish crossbill, both of which breed within its range.

This crossbill is mainly resident, but will irrupt south and west if its food source fails. This species will form flocks outside the breeding season, often mixed with other crossbills.

The crossbills are characterised by the mandibles crossing at their tips, which gives the group its English name. They are specialist feeders on conifer cones, and the unusual bill shape is an adaptation to assist the extraction of the seeds from the cone. The parrot crossbill is a specialist feeder on the cones of Scots pine.

Adult males tend to be red or orange in colour, and females green or yellow, but there is much variation.

This species is difficult to separate from red and Scottish crossbills, and plumage distinctions are negligible. It is slightly larger than other crossbills, measuring 16 to 18 cm (6.3 to 7.1 in) long and spanning 27 to 31 cm (11 to 12 in) across the wings. It is quite bulky and heavy weighing from 44 to 58.2 g (1.55 to 2.05 oz), with an average of 53 g (1.9 oz). The head and bill are larger than in either of the other species. The bill is thicker than those of its relatives, and the crossed tips are often not readily apparent. Extreme care is needed to identify this species. The deeper, harder choop or tyuup call is probably the best indicator.

Some pine-feeding populations currently assigned to red crossbill in southern Europe may possibly be better referred to either this species or alternatively to new species in their own right, but as yet, research into them is still at a very early stage.

Prioksko-Terrasny Nature Reserve

Prioksko-Terrasny Nature Biosphere Reserve (Russian: Приокско-Террасный государственный природный биосферный заповедник) is one of Russia's smallest zapovedniks (nature reserves), sprawling over an area of 5,000 hectares along the left bank of the Oka River in the Serpukhov District of Moskva Oblast. It was established in 1945 as part of the Moscow Nature Reserve and is home to 900 plant species, 130 bird species, and 54 mammal species. A wisent nursery was established in 1948 to populate the region with European bisons from the Belovezhskaya Pushcha and Western Caucasus. There is also a small herd of American bisons.

The very important to scientists was the fact that Prioksko-Terrasny biosphere reserve is situated on the border of the subzone of European taiga with the admixture of broad-leaved species and the subzone of broad-leaved forests. The functions of reserve were in preservation of typical ecosystems and unique observation of the natural dynamics of ecosystems and their components (biota, soil, water, climate), the study of the influence of anthropogenic factors on the change in the natural state of the natural environment at the territory of the biosphere reserve and training researchers in conservation and environmental monitoring.

Sawtooth National Forest

Sawtooth National Forest is a National Forest that covers 2,110,408 acres (854,052 ha) in the U.S. states of Idaho (~96 percent) and Utah (~4 percent). Managed by the U.S. Forest Service in the U.S. Department of Agriculture, it was originally named the Sawtooth Forest Reserve in a proclamation issued by President Theodore Roosevelt on May 29, 1905. On August 22, 1972 a portion of the forest was designated as the Sawtooth National Recreation Area (SNRA), which includes the Sawtooth, Cecil D. Andrus–White Clouds, and Hemingway–Boulders wilderness areas. The forest is managed as four units: the SNRA and the Fairfield, Ketchum, and Minidoka Ranger Districts.

Sawtooth National Forest is named for the Sawtooth Mountains, which traverse part of the SNRA. The forest also contains the Albion, Black Pine, Boise, Boulder, Pioneer, Raft River, Smoky, Soldier, Sublett, and White Cloud mountain ranges, as well as Hyndman Peak, the ninth-highest point in Idaho at 12,009 feet (3,660 m) above sea level. Sawtooth National Forest contains land cover types which include sagebrush steppe, spruce-fir forests, alpine tundra, and over 1,100 lakes and 3,500 miles (5,600 km) of rivers and streams. Plants and animals found only in the Sawtooth National Forest and adjacent lands include Christ's Indian paintbrush, Davis' springparsley, the South Hills crossbill, and the Wood River sculpin.

The area that is now Sawtooth National Forest was first occupied by people as early as 8000 BC and by the Shoshone tribe after 1700 AD. The first European descendants migrating from the eastern United States arrived in the area around the 1820s; they were mainly explorers, trappers, and prospectors, and they founded many of the current towns around what later became the forest. Sawtooth National Forest offers facilities for recreation, with four ski areas, whitewater and flatwater boating, hunting, 81 campgrounds, and over 1,000 mi (1,600 km) of trails and roads for hiking, mountain biking, and all-terrain vehicle use, including two National Recreation Trails.

Scottish crossbill

The Scottish crossbill (Loxia scotica) is a small passerine bird in the finch family Fringillidae. It is endemic to the Caledonian Forests of Scotland, and is the only terrestrial vertebrate species unique to the United Kingdom. The Scottish crossbill was confirmed as a unique species in August 2006, on the basis of having a distinctive bird song.The genus name Loxia is from Ancient Greek loxos, "crosswise", and scotica is Latin for Scottish". The Scottish Gaelic name for a crossbill is Cam-ghob, which literally means "squinty beaked".

Two-barred crossbill

The two-barred crossbill (Loxia leucoptera), known as the white-winged crossbill in North America, is a small passerine bird in the finch family Fringillidae. It has two subspecies, white-winged crossbill Loxia leucoptera leucoptera in North America, and two-barred crossbill Loxia leucoptera bifasciata in NE Europe and N Asia.

The scientific name is from Ancient Greek. Loxia is from loxos, "crosswise", and leucoptera means "white-winged" from leukos, "white" and pteron, "wing".This bird breeds in the coniferous forests of Alaska, Canada, northernmost United States and across Asia extending into northeast Europe. It nests in conifers, laying 3–5 eggs.

This crossbill is mainly resident, but will irregularly irrupt south if its food source fails. The American race seems to wander more frequently than the Eurasian subspecies. This species will form flocks outside the breeding season, often mixed with other crossbills. It is a rare visitor to western Europe, usually arriving with an irruption of red crossbills.

The crossbills are characterised by the mandibles crossing at their tips, which gives the group its English name. They are specialist feeders on conifer cones, and the unusual bill shape is an adaptation to assist the extraction of the seeds from the cone. Two-barred crossbill has a strong preference for larch (Larix), in Eurasia using Siberian larch (Larix sibirica) and Dahurian larch (L. gmelinii), and in North America Tamarack larch (L. laricina). It will also take rowan (Sorbus) berries, and in North America, also eastern hemlock (Tsuga canadensis) and white spruce (Picea glauca) cones.

Adult males tend to be red or pinkish in colour, and females green or yellow, but there is much variation. Two-barred is easier to identify than other crossbills, especially in North America, where only red crossbill and this species occur, but some care is still needed.

Within its Eurasian range, this species is smaller-headed and smaller-billed than parrot crossbill and Scottish crossbill, so the main confusion species both there and in North America is common or red crossbill.

The main plumage distinction from common crossbills is the white wingbars which give this species its English and scientific names. There are also white tips to the tertials. The adult male is also a somewhat brighter (pinker) red than other male crossbills. Some common crossbills occasionally show weak white wingbars, so care is needed with the correct identification of this species. The chip call is weaker and higher than that of common crossbill.

Another crossbill on Hispaniola was previously treated as a subspecies, Loxia leucoptera megaplaga, but is now treated as a distinct species, Hispaniolan crossbill, Loxia megaplaga. It is associated with the Hispaniolan pine Pinus occidentalis, and differs from two-barred crossbill in darker plumage and a stouter bill.

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