Two-barred Crossbill
Encyclopedia
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.
This bird breeds in the coniferous forests of Alaska
, Canada
, northernmost USA 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 eruption of Common Crossbill
s.
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 Eurasia
n 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.
, Florida
. Current speculation is that the bird may have been hit by a recreational vehicle
that was on its way south from the bird's natural range, and simply fell off after arrival in Florida. It is hoped that during the preparation of the specimen
an examination of the bird's stomach contents could help prove or disprove this hypothesis
. Alternatively, it is possible that the bird could have originated from the Hispaniola
n population.
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North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, is a small passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
in the finch
Finch
The true finches are passerine birds in the family Fringillidae. They are predominantly seed-eating songbirds. Most are native to the Northern Hemisphere, but one subfamily is endemic to the Neotropics, one to the Hawaiian Islands, and one subfamily – monotypic at genus level – is found...
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.
This bird breeds in the coniferous forests of Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, northernmost USA and across Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
extending into northeast Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
. It nests in conifers, laying 3-5 eggs.
This crossbill
Crossbill
The crossbill is a bird in the finch family . The three to five species are all classified in the genus Loxia. These birds are characterised by the mandibles crossing at their tips, which gives the group its English name...
is mainly resident, but will irregularly irrupt
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
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 eruption of Common Crossbill
Common Crossbill
The Common Crossbill is a small passerine bird in the finch family Fringillidae. It breeds in the spruce forests of North America, where it is known as Red Crossbill, as well as Europe and Asia; some populations breed in pine forests in certain areas of all three continents, and in North...
s.
The crossbills are characterised by the mandibles crossing at their tips, which gives the group its English
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
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
Larch
Larches are conifers in the genus Larix, in the family Pinaceae. Growing from 15 to 50m tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains further south...
(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
Rowan
The rowans or mountain-ashes are shrubs or small trees in genus Sorbus of family Rosaceae. They are native throughout the cool temperate regions of the Northern Hemisphere, with the highest species diversity in the mountains of western China and the Himalaya, where numerous apomictic microspecies...
Sorbus berries, and in North America, also Eastern Hemlock
Tsuga
Tsuga is a genus of conifers in the family Pinaceae. The common name hemlock is derived from a perceived similarity in the smell of its crushed foliage to that of the unrelated plant poison hemlock....
(Tsuga canadensis) and White spruce
White Spruce
Picea glauca is a species of spruce native to boreal forests in the north of North America, from central Alaska east to Newfoundland, and south to northern Montana, Minnesota, Wisconsin, Michigan, upstate New York, Vermont, New Hampshire, and Maine; there is also an isolated population in the...
(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 Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
n range, this species is smaller-headed and smaller-billed than Parrot Crossbill
Parrot Crossbill
The Parrot Crossbill is a small passerine bird in the finch family Fringillidae.This bird breeds in the pine forests of northwest Europe and into western Russia...
and Scottish Crossbill
Scottish Crossbill
The Scottish Crossbill is a small passerine bird in the finch family Fringillidae. It is endemic to the Caledonian Forests of Scotland, and is the only vertebrate unique to the United Kingdom...
, 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
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
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
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
was previously treated as a subspecies, Loxia leucoptera megaplaga, but is now treated as a distinct species, Hispaniolan Crossbill
Hispaniolan Crossbill
The Hispaniolan Crossbill is a crossbill that is endemic to the island of Hispaniola in the Caribbean and therefore only found in Haiti and the Dominican Republic....
, Loxia megaplaga. It is associated with the Hispaniolan pine Pinus occidentalis, and differs from Two-barred Crossbill in darker plumage and a stouter bill.
Exceptional southern vagrancy in America?
On 11 January 2007 a White-winged Crossbill was found dead in the parking lot at Long Pine Key Picnic Area in Everglades National ParkEverglades National Park
Everglades National Park is a national park in the U.S. state of Florida that protects the southern 25 percent of the original Everglades. It is the largest subtropical wilderness in the United States, and is visited on average by one million people each year. It is the third-largest...
, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
. Current speculation is that the bird may have been hit by a recreational vehicle
Recreational vehicle
Recreational vehicle or RV is, in North America, the usual term for a Motor vehicle or trailer equipped with living space and amenities found in a home.-Features:...
that was on its way south from the bird's natural range, and simply fell off after arrival in Florida. It is hoped that during the preparation of the specimen
Specimen
A specimen is a portion/quantity of material for use in testing, examination, or study.BiologyA laboratory specimen is an individual animal, part of an animal, a plant, part of a plant, or a microorganism, used as a representative to study the properties of the whole population of that species or...
an examination of the bird's stomach contents could help prove or disprove this hypothesis
Hypothesis
A hypothesis is a proposed explanation for a phenomenon. The term derives from the Greek, ὑποτιθέναι – hypotithenai meaning "to put under" or "to suppose". For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that one can test it...
. Alternatively, it is possible that the bird could have originated from the Hispaniola
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
n population.
External links
Books
- Benkman C. W. 1992. White-winged Crossbill (Loxia leucoptera). In The Birds of North America, No. 27. (A. Poole, P. Stettenheim, and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, DC: The American Ornithologists’ Union.
Thesis
- Benkman CW. Ph.D. (1985). THE FORAGING ECOLOGY OF CROSSBILLS IN EASTERN NORTH AMERICA (AVES, BREEDING BEHAVIOR, MORPHOLOGY, CONIFERS). State University of New York at Albany, United States, New York.
Articles
- Benkman CW. (1987). Crossbill Foraging Behavior Bill Structure and Patterns of Food Profitability. Wilson Bulletin. vol 99, no 3. p. 351-368.
- Benkman CW. (1987). Food Profitability and the Foraging Ecology of Crossbills. Ecological Monographs. vol 57, no 3. p. 251-267.
- Benkman CW. (1989). Intake Rate Maximization and the Foraging Behavior of Crossbills. Ornis Scandinavica. vol 20, no 1. p. 65-68.
- Benkman CW. (1990). Intake Rates and the Timing of Crossbill Reproduction. Auk. vol 107, no 2. p. 376-386.
- Benkman CW. (1994). Comments on the ecology and status of the hispaniolan crossbill (Loxia leucoptera megaplaga), with recommendations for its conservation. Caribbean Journal of Science. vol 30, no 3-4. p. 250-254.
- Benkman CW. (1997). Feeding behavior, flock-size dynamics, and variation in sexual selection in crossbills. Auk. vol 114, no 2. p. 163-178.
- Coady G. (2001). First nest record of white-winged crossbill in the greater Toronto area. Ontario Birds. vol 19, no 3. p. 101-111.
- Deviche P. (1997). Seasonal reproductive pattern of white-winged Crossbills in interior Alaska. Journal of Field Ornithology. vol 68, no 4. p. 613-621.
- Deviche P. (2000). Timing, pattern, and extent of first prebasic molt of White-winged Crossbills in Alaska. Journal of Field Ornithology. vol 71, no 2. p. 217-226.
- Deviche P & Hahn TP. (1995). SEasonal reproductive pattern of interior Alaska white-winged crossbills (Loxia leucoptera). American Association for the Advancement of Science, Arctic Division. p. Landscapes Human ecology, landscape ecology, earth system science.
- Deviche P & Sharp PJ. (2001). Reproductive endocrinology of a free-living, opportunistically breeding passerine (White-winged Crossbill, Loxia leucoptera). General and Comparative Endocrinology. vol 123, no 3. p. 268-279.
- Elmberg J. (1993). Song differences between North American and European White-winged Crossbills (Loxia leucoptera). The Auk. vol 110, no 2. p. 385.
- Eykhler V & Vasyukova TT. (1981). A New Species of the Genus Docophorulus Mallophaga Philopteridae from the White-Winged Crossbill Loxia-Leucoptera-Bifasciata. Entomological Review. vol 60, no 3. p. 99-101.
- Fischer S, Mauersberger G, Schielzeth H & Witt K. (1992). 1ST BREEDING RECORD OF 2-BARRED CROSSBILL (LOXIA-LEUCOPTERA) IN CENTRAL-EUROPE. Journal Fur Ornithologie. vol 133, no 2. p. 197-202.
- Gallant D. (2004). White-winged crossbills obtain forage from river otter Feces. Wilson Bulletin. vol 116, no 2. p. 181-184.
- Gordon P, Morlan J & Roberson D. (1989). First Record of the White-Winged Crossbill in California USA. Western Birds. vol 20, no 2. p. 81-88.
- Groth JG. (1992). Further Information on the Genetics of Bill Crossing in Crossbills. The Auk. vol 109, no 2. p. 383.
- Groth JG. (1992). White-Winged Crossbill Breeding in Southern Colorado with Notes on Juveniles Calls. Western Birds. vol 23, no 1. p. 35-38.
- Hahn TP, Pereyra ME & Sharbaugh SM. (2003). Effects of photoperiod on brain GnRH plasticity and peripheral reproductive physiology in three species of cardueline finches. Society for Neuroscience Abstract Viewer & Itinerary Planner. p. 611.
- Hahn TP, Pereyra ME, Sharbaugh SM & Bentley GE. (2004). Physiological responses to photoperiod in three cardueline finch species. General and Comparative Endocrinology. vol 137, no 1. p. 99-108.
- Hahn TP, Wingfield JC, Mullen R & Deviche PJ. (1995). ENDOCRINE BASES OF SPATIAL AND TEMPORAL OPPORTUNISM IN ARCTIC-BREEDING BIRDS. American Zoologist. vol 35, no 3. p. 259-273.
- Hobson KA & Bayne E. (2000). Breeding bird communities in boreal forest of western Canada: Consequences of "unmixing" the mixedwoods. Condor. vol 102, no 4. p. 759-769.
- Kepler AK, Kepler CB & Dod A. (1975). FIRST NEST RECORD OF WHITE-WINGED CROSSBILL IN HISPANIOLA. Condor. vol 77, no 2. p. 220-221.
- Koenig WD & Knops JMH. (2001). Seed-crop size and eruptions of North American boreal seed-eating birds. Journal of Animal Ecology. vol 70, no 4. p. 609-620.
- Latta SC, Sondreal ML & Brown CR. (2000). A hierarchical analysis of nesting and foraging habitat for the conservation of the Hispaniolan White-winged crossbill (Loxia leucoptera megaplaga). Biological Conservation. vol 96, no 2. p. 139-150.
- Latta SC, Sondreal ML & Mejia DA. (2002). Breeding behavior of the endangered Hispaniolan Crossbill (Loxia megaplaga). Ornitologia Neotropical. vol 13, no 3. p. 225-234.
- MacDougall-Shackleton SA, Deviche PJ, Crain RD, Ball GF & Hahn TP. (2001). Seasonal changes in brain GnRH immunoreactivity and song-control nuclei volumes in an opportunistically breeding songbird. Brain Behavior and Evolution. vol 58, no 1. p. 38-48.
- McNair DB. (1990). First Modern Record of White-Winged Crossbill in Georgia USA a Commentary. Oriole. vol 53, no 4. p. 49-50.
- Mundinger PC. (1979). Call Learning in the Carduelinae Ethological and Systematic Considerations. Systematic Zoology. vol 28, no 3. p. 270-283.
- Nankinov DN, Ilkov PG & Stoychev KS. (1999). White-winged crossbill (Loxia leucoptera bifasciata C. L. Brehm, 1827) in Bulgaria. Acta Zoologica Bulgarica. vol 51, no 1. p. 49-51.
- Oberle MW. (1986). First Modern Record of White-Winged Crossbill in Georgia USA. Oriole. vol 51, no 2-3. p. 25-27.
- Oberle MW & Hahn T. (1994). More on the White-winged crossbill in Georgia. Oriole. vol 59, no 1. p. 26-27.
- Parchman TL & Benkman CW. (2002). Diversifying coevolution between crossbills and black spruce on Newfoundland. Evolution. vol 56, no 8. p. 1663-1672.
- Parchman TL, Benkman CW & Britch SC. (2006). Patterns of genetic variation in the adaptive radiation of New World crossbills (Aves : Loxia). Molecular Ecology. vol 15, no 7. p. 1873-1887.
- Pereyra ME, Sharbaugh SM & Hahn TP. (2005). Interspecific variation in photo-induced GnRH plasticity among nomadic cardueline finches. Brain Behavior and Evolution. vol 66, no 1. p. 35-49.
- Pulliainen E. (2002). Chemical composition of the seed food of late-summer-breeding two-barred crossbills Loxia leucoptera. Aquilo Ser Zoologica. vol 30, p. 79-81.
- Sealy SG, Sexton DA & Collins KM. (1980). Observations of a White-Winged Crossbill Loxia-Leucoptera Invasion of Southeastern Manitoba Canada. Wilson Bulletin. vol 92, no 1. p. 114-116.
- Steinberg B & Tozer R. (2003). White-winged Crossbill predation by Blue Jay. Ontario Birds. vol 21, no 1. p. 34-37.
- Stradi R, Rossi E, Celentano G & Bellardi B. (1996). Carotenoids in bird plumage: The pattern in three Loxia species and in Pinicola enucleator. Comparative Biochemistry and Physiology B-Biochemistry & Molecular Biology. vol 113, no 2. p. 427-432.
- West GC. (1974). ABNORMAL BILL OF A WHITE-WINGED CROSSBILL. Auk. vol 91, no 3. p. 624-626.
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