Yellow-backed Oriole
Encyclopedia
The Yellow-backed Oriole (Icterus chrysater) is a species of bird
in the Icteridae family.
species. Howell and Webb (1995) note that this species tends to average 21.5 cm (8.5 in) in length from beak to tail; making Icterus chrysater a relatively medium-sized species. Exposed skin and claws are bluish-black; in adults, the bill is black, with the base of the mandible
becoming bluish-grey.
Adult males display strongly contrasting
yellow and black plumage. The wings, tail, shoulders, throat, and face are all black; by contrast, the back and underparts are an extremely bright yellow. Adult females closely resemble males, but yellow parts appear slightly greenish. Despite differences in plumage coloration between sexes, it is likely that this species is extremely difficult to sex in the field.
Immature yellow-backed orioles resemble adult females in overall pattern, but are greener; additionally, the flight feathers, which are black in females, are dark brown. Immature yellow-backed orioles are easily distinguished from adult females by their olive eye-line.
Similar species include Icterus nigrogularis
.
, Colombia
, El Salvador
, Guatemala
, Honduras
, Mexico
, Nicaragua
, Panama
, and Venezuela
.
This species is usually found in regions that are less than 900 meters in altitude, though in Central and South America populations are often seen residing at elevations greater than 1000 m. The upper altitude limit for populations observed in the wild appears to be about 3 km.
The nests of this species are shallow, dangling baskets that are usually hung from the edge of a tree limb. Members of this species appear to prefer to attach nests to the tips of palm fronds (Jaramillo and Burke 1999). Nests are usually woven of fine grasses, giving them a springy texture (Wetmore et al. 1984). Nests of this species are normally hung in the canopy of mature trees that are at least seven meters in height.
The eggs of this species are whitish, with purple scrawlings that are concentrated near the broad end of the egg. The eggs are commonly marked with evenly distributed brown lines (Jaramillo and Burke 1999; Wetmore et al. 1984).
Both sexes are known to sing, which appears to be common to orioles that breed in tropical climates (Price et al. 2007). Vocalizations are generally delivered from perches high in trees (ridgely and Tudor, 1989).
Jaramillo and Burke (1999) also describe other vocalizations in this species’ repertoire. The most commonly used call has been described by Jaramillo and Burke (1999) as a “nasal ‘chert’”, but other calls include a “whistling chatter” and a “nasal alarm”.
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 Icteridae family.
Physical description
Yellow-backed orioles are a yellow-bodied, sexually monomorphicSexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
species. Howell and Webb (1995) note that this species tends to average 21.5 cm (8.5 in) in length from beak to tail; making Icterus chrysater a relatively medium-sized species. Exposed skin and claws are bluish-black; in adults, the bill is black, with the base of the mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
becoming bluish-grey.
Adult males display strongly contrasting
Contrast (vision)
Contrast is the difference in visual properties that makes an object distinguishable from other objects and the background. In visual perception of the real world, contrast is determined by the difference in the color and brightness of the object and other objects within the same field of view...
yellow and black plumage. The wings, tail, shoulders, throat, and face are all black; by contrast, the back and underparts are an extremely bright yellow. Adult females closely resemble males, but yellow parts appear slightly greenish. Despite differences in plumage coloration between sexes, it is likely that this species is extremely difficult to sex in the field.
Immature yellow-backed orioles resemble adult females in overall pattern, but are greener; additionally, the flight feathers, which are black in females, are dark brown. Immature yellow-backed orioles are easily distinguished from adult females by their olive eye-line.
Similar species include Icterus nigrogularis
South American Yellow Oriole
The Yellow Oriole, Icterus nigrogularis, is a passerine bird in the family Icteridae. It should not be confused with the Australasian Yellow Oriole, Oriolus flavocinctus, which is an Old World oriole...
.
Geographic distribution
Yellow-backed orioles are found throughout Central America and northern South America. In particular, the species is divided into three allopatric populations. One population, designated as the subspecies I. c. giraudii, is endemic to southern Central America, and includes Nicaragua, Panama, and Colombia. The northernmost populations comprise the subspecies I. c. chrysater and I. c. mayanensis; these subspecies are found in northern Central America and in southern Mexico. Nations that have native populations of this species include BelizeBelize
Belize is a constitutional monarchy and the northernmost country in Central America. Belize has a diverse society, comprising many cultures and languages. Even though Kriol and Spanish are spoken among the population, Belize is the only country in Central America where English is the official...
, Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
, El Salvador
El Salvador
El Salvador or simply Salvador is the smallest and the most densely populated country in Central America. The country's capital city and largest city is San Salvador; Santa Ana and San Miguel are also important cultural and commercial centers in the country and in all of Central America...
, Guatemala
Guatemala
Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...
, Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
, Nicaragua
Nicaragua
Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...
, Panama
Panama
Panama , officially the Republic of Panama , is the southernmost country of Central America. Situated on the isthmus connecting North and South America, it is bordered by Costa Rica to the northwest, Colombia to the southeast, the Caribbean Sea to the north and the Pacific Ocean to the south. The...
, and Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
.
Habitats
Yellow-backed orioles are able to tolerate a wide variety of habitats, but prefer open, mixed pine-oak woodlands and dry scrub forest. This species has also been sighted in banana plantations. It has occasionally colonized lowland deciduous forest.This species is usually found in regions that are less than 900 meters in altitude, though in Central and South America populations are often seen residing at elevations greater than 1000 m. The upper altitude limit for populations observed in the wild appears to be about 3 km.
Reproduction
Yellow-backed orioles are monogamous; like many species of the genus Icterus, yellow-backed orioles breed once yearly with a single mate.The nests of this species are shallow, dangling baskets that are usually hung from the edge of a tree limb. Members of this species appear to prefer to attach nests to the tips of palm fronds (Jaramillo and Burke 1999). Nests are usually woven of fine grasses, giving them a springy texture (Wetmore et al. 1984). Nests of this species are normally hung in the canopy of mature trees that are at least seven meters in height.
The eggs of this species are whitish, with purple scrawlings that are concentrated near the broad end of the egg. The eggs are commonly marked with evenly distributed brown lines (Jaramillo and Burke 1999; Wetmore et al. 1984).
Agonistic interactions
Yellow-backed orioles have been observed to congregate in small flocks of up to eight individuals (Wetmore et al. 1984); these flocks are probably family units, as they are composed of individuals at varying stages of maturity. This species occasionally joins mixed-species flocks that include band-backed wrens, jays, and other medium-sized orioles (Jaramillo and Burke 1999; Wetmore et al. 1984)Communication
This species has a clear, whistling voice, with a song resembling that of spot-breasted orioles (Icterus pectoralis). The song generally consists of a series of clear notes, but it acquires a muddy, warbled quality among populations native to southern Central America (Jaramillo and Burke 1999; Skutch 1996).Both sexes are known to sing, which appears to be common to orioles that breed in tropical climates (Price et al. 2007). Vocalizations are generally delivered from perches high in trees (ridgely and Tudor, 1989).
Jaramillo and Burke (1999) also describe other vocalizations in this species’ repertoire. The most commonly used call has been described by Jaramillo and Burke (1999) as a “nasal ‘chert’”, but other calls include a “whistling chatter” and a “nasal alarm”.
Diet
Yellow-backed orioles are insectivorous. Their diet consists primarily of caterpillars, wasps, ants, weevils, and other arthropods. This species' diet is often augmented with bananas and may also include nectar from balsa and Heliconia (Leck, 1974).Feeding behaviors
This species is often observed foraging in family units or in pairs (Jaramillo and Burke 1999). Insects are hunted by probing the bark of trees or the leaves of epiphytes. While foraging for nectar, this species sometimes practices "nectar robbing", puncturing the base of an unopened flower to gain access to nectar (Morton 1979)External links
- Yellow-backed oriole species account Encyclopedia of Life
- Yellow-backed Oriole videos on the Internet Bird Collection
- Yellow-backed Oriole photo gallery VIREO