Piranga ludovicianawestern tanager

Ge­o­graphic Range

The ge­o­graphic re­gion of west­ern tan­agers (Pi­ranga lu­dovi­ciana) fol­lows the for­est, rang­ing from the west­ern coasts of North Amer­ica and Cen­tral Amer­ica from Alaska all the way to Panama. This re­gion stretches as far east as the North­west Ter­ri­to­ries in Canada and the west­ern edge of North Dakota, Ne­braska, and Texas. Their main res­i­dency and breed­ing ter­ri­tory is in the far north­ern re­gion of Canada and they mi­grate south dur­ing the win­ter. How­ever, they have been known to breed in their win­ter­ing re­gions of South Amer­ica. (Meyer, 2006; Mon­roy-Ojeda, et al., 2013)

Habi­tat

West­ern tan­agers ar­rive in their breed­ing grounds in the spring and breed in open conif­er­ous forests and mixed wood­lands. They leave the north­ern lo­ca­tions in late sum­mer and spend the win­ters in the open moun­tain pine wood­lands, parks, gar­dens, desert oases, ri­par­ian areas, and or­chards. In their win­ter­ing range, they oc­cupy pine and pine-oak wood­lands as well as low-canopied scrub forests. They have been seen in el­e­va­tions as high as 10,000 feet and as low as 330 feet. (Meyer, 2006)

  • Range elevation
    100 to 3,050 m
    328.08 to ft
  • Average elevation
    2,520 m
    ft

Phys­i­cal De­scrip­tion

West­ern tan­agers av­er­age around 18 cm in length, with an av­er­age weight of 28 grams. They have a wingspan of ap­prox­i­mately 28 to 30 cm, with rounded wings and a fan-shaped tail. Their bill is an all-pur­pose beak, mean­ing they can catch food, build a nest, preen, dig holes, and care for their young. Their eyes are sepia brown in ado­les­cent birds, gray­ish brown or black in adult males, and red­dish brown to burnt umber in adult fe­males. Among males, their breast is pri­mar­ily yel­low, their back and wings are pri­mar­ily black, and their en­tire head is red. Their wings have two bright yel­low wing bars. Fe­males are pale in com­par­i­son, with an olive green upper back and head. Their wings are grey with two wing bars and their tails are grey­ish brown or olive green. After hatch­ing, young have white or pale gray down on their head, back, and wings, and their wing bars be­come vis­i­ble after 10 days. (Hudon, 1999; "West­ern Tan­ager", 2013)

  • Sexual Dimorphism
  • sexes colored or patterned differently
  • male more colorful
  • Range mass
    24 to 36 g
    0.85 to 1.27 oz
  • Average mass
    28 g
    0.99 oz
  • Range length
    16 to 19 cm
    6.30 to 7.48 in
  • Average length
    18 cm
    7.09 in
  • Range wingspan
    28 to 30 cm
    11.02 to 11.81 in

Re­pro­duc­tion

West­ern tan­agers are monog­a­mous. Pairs form dur­ing mi­gra­tion or on the win­ter­ing grounds, mostly in South Amer­ica. Pairs that form on the win­ter­ing grounds may mi­grate to­gether to the breed­ing grounds. Males es­tab­lish and de­fend their ter­ri­tory by singing and chas­ing away in­trud­ers. How­ever, males are not known to per­form any dis­plays to at­tract mates. (Hudon, 1999; Meyer, 2006)

The ear­li­est birds may ar­rive on the breed­ing grounds in April, while most birds ar­rive by early May. On av­er­age, fe­males and first-year males ar­rive at breed­ing grounds later. Both sexes are sex­u­ally ma­ture after two years. Al­though west­ern tan­agers are so­cially monog­a­mous, males are known to move out­side the ter­ri­tory they de­fend to mate with other fe­males. Fe­males build small cup-like nests from grass and twigs in about 4 to 5 days. Males feed the fe­males dur­ing the nest build­ing and the egg lay­ing process. On av­er­age, the eggs are 23 mm long, about 3.35 grams, and are pale blue or bluish green. The eggs are blotched with brown­ish speck­les that form a thick wreath around the larger end of the egg. Fe­males lay around 3 to 5 eggs, which takes about a day per egg. The eggs are in­cu­bated by the fe­male for ap­prox­i­mately 13 days. The young are fed by both par­ents and fledge within 15 days. The young do not be­come in­de­pen­dent until about two weeks after fledg­ing. West­ern tan­agers may leave their breed­ing grounds as early as July, but typ­i­cally do not begin mi­gra­tion until Au­gust. (Davis, 2001; Hudon, 1999; Meyer, 2006)

  • Breeding interval
    Western tanagers breed once yearly.
  • Breeding season
    These birds breed from mid-April to mid-August.
  • Range eggs per season
    1 to 5
  • Average eggs per season
    4
  • Range time to hatching
    11 to 13 days
  • Range fledging age
    11 to 15 days
  • Average time to independence
    14 days
  • Range age at sexual or reproductive maturity (female)
    1 to 3 years
  • Range age at sexual or reproductive maturity (male)
    1 to 3 years

Fe­male west­ern tan­agers in­cu­bate the eggs alone, but both males and fe­males feed the young. Both par­ents con­tinue feed­ing the fledg­lings for about two more weeks after they have left the nest. The young are known to stay on the breed­ing grounds even after the adults have left. (Hudon, 1999; Meyer, 2006)

  • Parental Investment
  • altricial
  • male parental care
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • male
  • pre-weaning/fledging
    • provisioning
      • male
      • female
    • protecting
      • male
  • pre-independence
    • provisioning
      • male
      • female
    • protecting
      • male
      • female

Lifes­pan/Longevity

West­ern tan­agers have been known to live up to 15.3 years, but their av­er­age life span is around 8 years. In ad­di­tion to pre­da­tion, mor­tal­ity can also be caused by food de­pri­va­tion re­sult­ing from se­vere weather. (Hudon, 1999; Lee, 2012; Ma­g­a­l­haes, 2012)

  • Range lifespan
    Status: wild
    1 to 15 years
  • Range lifespan
    Status: captivity
    1 to 15 years

Be­hav­ior

West­ern tan­ager mi­grate long dis­tances and mi­grate alone, in pairs, or in groups of about 30. Mi­gra­tion oc­curs at night, at very high al­ti­tudes. They form loose as­so­ci­a­tions with other bird species such as Townsend's war­blers, pur­ple finches, and moun­tain chick­adees. Males chase other males that in­trude in their ter­ri­tory and fe­males chase other fe­males. West­ern tan­agers also charge at smaller birds and phys­i­cal con­tact is some­times made due to the re­ac­tion of the star­tled vic­tim. West­ern tan­agers can be dif­fi­cult to spot be­cause they for­age in the upper branches of trees and move slowly and de­lib­er­ately, but in flight they are swift and di­rect. (Meyer, 2006; Hudon, 1999; Meyer, 2006)

Home Range

There are a few stud­ies of home ter­ri­to­ries for west­ern tan­agers. A conifer for­est in Idaho av­er­aged a home range size of 39,100 square me­ters, while in Mon­tana; they have an av­er­age home range of 28,300 square me­ters. (Davis, 2001; Samuel, et al., 1985)

Com­mu­ni­ca­tion and Per­cep­tion

West­ern tan­agers gen­er­ally com­mu­ni­cate through song. Their song is sim­i­lar to Amer­i­can robins', but pauses after each phrase and sounds more hoarse. Their calls are short and ex­plo­sive and used by both sexes and their young. The young sound more mu­si­cal, while the fe­male is less elo­quent. Her song is more repet­i­tive, with an av­er­age of 2 to 5 phrases. Males have more ar­tic­u­lated and more fre­quent vo­cal­iza­tions, with 4 to 7 song phrases. Males sing pri­mar­ily on the breed­ing grounds. Males are at­tracted to the play­back of fe­male songs and males will also counter-sing when they hear neigh­bor­ing males. Song rates are most fre­quent in the morn­ing and slowly de­crease dur­ing the day. When a fe­male per­ceives a threat, she gives a se­ries of ner­vous calls. When the male hears the ner­vous call of his mate, he gives a loud se­ries of ner­vous calls and flies from branch to branch. (Hudon, 1999; Stalling, 2012)

Food Habits

West­ern tan­agers are in­sec­ti­vores and catch in­sects while they are in flight. Vespid wasps are not eaten by other mi­gra­tory birds, but are often pre­ferred by west­ern tan­agers. They also eat fruits and nec­tar from plants. Dur­ing the win­ter they eat both in­sects and fruit. (Carlise, et al., 2012; Hudon, 1999)

  • Animal Foods
  • insects
  • Plant Foods
  • fruit
  • nectar
  • sap or other plant fluids

Pre­da­tion

There are sev­eral birds that prey on west­ern tan­agers. Com­mon preda­tors are hawks, owls, and jays. Nest preda­tors in­clude owls, jays, black bears, prairie rat­tlesnakes, bull snakes, com­mon ravens, Amer­i­can crows, squir­rels, and even do­mes­tic cats. Their anti-preda­tor adap­ta­tions in­clude tail cock­ing, wing flap­ping, and loud ner­vous calls. West­ern tan­agers swoop to­wards in­trud­ers when they are too close to their nest. (Hudon, 1999; Meyer, 2006)

Ecosys­tem Roles

West­ern tan­agers are prey for many birds and mam­mals. Brown-headed cow­birds are known to par­a­sitize west­ern tan­ager nests and also re­duce the num­ber of west­ern tan­agers that are able to fledge per nest. West­ern tan­agers are known to mob cow­birds, but cow­birds are still able to re­move some of the west­ern tan­agers' eggs and lay their own. After hatch­ing, west­ern tan­agers will raise the cow­birds to fledg­ing. Blowfly lar­vae are also known to sub­cu­ta­neously in­vade fledg­lings, which re­sults in death. (Davis, 2001; Hudon, 1999; Meyer, 2006)

Com­men­sal/Par­a­sitic Species

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

West­ern tan­agers are known to eat sev­eral in­sects and are viewed as a form of pest con­trol for hu­mans. (Hudon, 1999)

  • Positive Impacts
  • controls pest population

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known neg­a­tive ef­fects of west­ern tan­agers on hu­mans.

Con­ser­va­tion Sta­tus

West­ern tan­agers are not threat­ened, in fact, the species has a large range. West­ern tan­agers are pro­tected under the U.S. Mi­gra­tory Bird Act. (Birdlife In­ter­na­tional, 2012)

Other Com­ments

West­ern tan­agers have a red pig­ment on their faces caused by rho­dox­an­thin, a pig­ment that is very rare in birds. This pig­men­ta­tion comes from the in­sects west­ern tan­agers eat, and the in­sects ac­quire it from plants. Their yel­low color orig­i­nates from the melanin pig­mented by carotenoids. (Hudon, 1991; Hudon, 1999)

Con­trib­u­tors

Jeneil Boles (au­thor), Uni­ver­sity of Wyoming, Hay­ley Lanier (ed­i­tor), Uni­ver­sity of Wyoming - Casper, Leila Si­cil­iano Mar­tina (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

choruses

to jointly display, usually with sounds, at the same time as two or more other individuals of the same or different species

crepuscular

active at dawn and dusk

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

male parental care

parental care is carried out by males

migratory

makes seasonal movements between breeding and wintering grounds

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

taiga

Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

Ref­er­ences

The Cor­nell Lab of Or­nithol­ogy. 2013. "West­ern Tan­ager" (On-line). All About Birds. Ac­cessed No­vem­ber 24, 2013 at http://​www.​allaboutbirds.​org/​guide/​western_​tanager/​id.

Birdlife In­ter­na­tional, 2012. "Pi­ranga lu­dovi­ciana" (On-line). The IUCN Red List of Threat­ened Species. Ac­cessed No­vem­ber 06, 2013 at http://​www.​iucnredlist.​org/​details/​22722471/​0.

Carlise, J., K. Olm­stead, C. Richart, D. Swan­son. 2012. Food avail­abil­ity, for­ag­ing be­hav­ior, and diet of au­tumn mi­grant land­birds in the Boise Foothills of South­west­ern Idaho. The Con­dor, 114.3: 449-461.

Davis, C. 2001. "Cal­i­for­nia Part­ners in Flight Conif­er­ous Bird Con­ser­va­tion Plan for the West­ern Tan­ager (Pi­ranga lu­dovi­ciana)" (On-line). Ac­cessed No­vem­ber 01, 2013 at http://​www.​prbo.​org/​calpif/​htmldocs/​species/​conifer/​wetacct.​html.

Hudon, J. 1999. The Birds of North Amer­ica. Philadel­phia, PA: The Acad­emy of Nat­ural Sci­ences.

Hudon, J. 1991. Un­usual carotenoid use by the west­ern tan­ager (Pi­ranaga lu­dovi­ciana) and its evo­lu­tion­ary im­pli­ca­tions. Cana­dian Jour­nal of Zo­ol­ogy, 69: 2311-2320.

Lee, V. 2012. "West­ern Tan­ager Tags: Birds, Through the Look­ing Glass of Val Lee" (On-line). Ac­cessed No­vem­ber 02, 2013 at http://​birdsbyval.​wordpress.​com/​2012/​04/​07/​through-the-looking-glass-of-val-lee-western-tanager/​.

Ma­g­a­l­haes, J. 2012. "AnAge entry for Pi­ranga lu­dovi­ciana" (On-line). The An­i­mal Aging and Longevity Data­base. Ac­cessed No­vem­ber 13, 2013 at http://​genomics.​senescence.​info/​species/​entry.​php?​species=Piranga_​ludoviciana.

Meyer, R. 2006. "Fire Ef­fects In­for­ma­tion Sys­tem" (On-line). Ac­cessed No­vem­ber 04, 2013 at http://​www.​fs.​fed.​us/​database/​feis/​.

Mon­roy-Ojeda, A., M. Grosse­let, G. Ruiz, E. Del Valle. 2013. Win­ter site fi­delity and win­ter res­i­dency of six mi­gra­tory neotrop­i­cal species in Mex­ico. The Wil­son Jour­nal of Or­nithol­ogy, 125.1: 192 -196.

Samuel, M., D. Pierce, E. Gar­ton. 1985. Iden­ti­fy­ing areas of con­cen­trated use within the home range. Jour­nal of An­i­mal Ecol­ogy, 54: 711-719.

Stalling, D. 2012. "Mon­tana Out­doors Por­trait: West­ern Tan­ager Pi­ranga lu­dovi­ciana" (On-line). Ac­cessed No­vem­ber 04, 2013 at http://​fwp.​mt.​gov/​mtoutdoors/​HTML/​articles/​portraits/​2012/​westerntanager.​htm#.​UniHkfmsj5w.