Yellow-tailed orioles (Icterus mesomelas) are found in Central and South America (Monroe and Sibley 1993). They are found predominantly below 500 m altitude. There are five described subspecies: Icterus mesomelas mesomelas, Icterus mesomelas salvinii, Icterus mesomelas carrikeri, Icterus mesomelas taczanowskii, Icterus mesomelas xantholemus (Clemens 2007). (Clemens, 2007; Monroe and Sibley, 1993)
Icterus m. mesomelas and I. m. salvinii can be found in Central America. Icterus m. mesomelas can be found in the tropical southeast of Mexico, which extends from south Veracruz to the city of Oaxaca; they are also found in Belize and Honduras (Clemens 2007). Icterus m. salvinii is found in the Caribbean lowlands of Nicaragua, east Costa Rica continuing to extreme northwest Panama (Jaramillo and Burke 1999). (Clemens, 2007; Jaramillo and Burke, 1999)
The other three subspecies can be found further south along the Pacific lowlands. Icterus m. carrikeri is found from Panama to northwestern Columbia and northwestern Venezuela. In Panama, the range extends along the Pacific slope from the Canal eastward and in the north it extends from the lowlands of Colombia northwards of the Santa Marta Mountains and the Magdalena Valley. Furthermore, the geographic range includes the east of Guajira, North of Santander and extends into the northwest of Venezuela (Jaramillo and Burke 1999). In Venezuela, yellow-tailed orioles are found around the Lake Maracaibo basin, in Zulia, Tachira and Merida (Ridgely and Tudor 2001). (Jaramillo and Burke, 1999; Ridgely and Tudor, 2001)
Icterus m. taczanowskii is endemic to the Pacific lowlands of western Ecuador and northwest Peru (Clements 2007). In Peru, the range stretches from Piura in the north (Jaramillo and Burke 1999) to the Pacific Coast to Lambayeque. Their range is separated by the Andes mountain range, unlike the continuous distribution from north to south and then continues into the upper Maranon Valley and further south to La Libertad (Ridgely and Tudor 2001).This is the only part of South America where the range of I. mesomelas is disrupted. (Clemens, 2007; Jaramillo and Burke, 1999; Ridgely and Tudor, 2001)
Icterus m. xantholemus is known only from Ecuador. Although some experts indicate that these individuals may represent immature I. mesomelas (Clemens 2007), others propose that it could be a hybrid between two unknown species of Icterus (Sibley and Monroe 1990), others treat it as a valid species (Blake et al. 1968). (Blake, et al., 1968; Clemens, 2007; Sibley and Monroe, 1990)
Yellow-tailed orioles prefer tropical lowlands below 500 m elevation (Clemens 2007). They can be found in woodlands, clearings, and brushland. They are often found near stands of Heliconia plants, Manila hemp, or in agricultural areas, showing a clear preference for banana plantations. They inhabit areas near water and are the only Central American oriole that prefers swamps (Jaramillo and Burke 1999). They forage in pairs for insects, spiders, and fruits (Stiles and Skutch 1989). (Clemens, 2007; Jaramillo and Burke, 1999; Stiles and Skutch, 1989)
Yellow-tailed orioles are medium-sized birds, ranging from 20 to 23.6 cm long (Howell and Webb 1995) and weighing around 70 grams (Stiles and Skutch 1989). This species is identified by the golden yellow color of their tail and stripe on their wing coverts. They differ from yellow-backed orioles (Icterus chrysater) in that the latter has yellow back, entirely black tail and no yellow on the wings. A yellow tail is found in all ages of this species. Other features that distinguish yellow-tailed orioles from other orioles are white markings on the wings, yellow shoulders, and bristly forehead feathers (Jaramillo and Burke 1999). (Howell and Webb, 1995; Jaramillo and Burke, 1999; Stiles and Skutch, 1989)
Like most tropical orioles, this species is sexually monomorphic: males cannot be differentiated from females based only on appearance. However, certain differences have been identified between adult, immature, and juvenile birds (Howell and Webb 1995). (Howell and Webb, 1995)
An adult yellow-tailed oriole has dark brown eyes and a black down-curved bill; the black coloration continues to the lores and anterior auriculars giving the illusion of a black mask. This mask extends to the chin, throat and upper breast as a bib. In addition, the back and scapulars display the same black coloration. The neck has orange-yellow stripes which fade along the back. The tail is long, moderately graduated, and the uppertail coverts are yellow (Howell and Webb 1995). Finally, the legs and feet are a mixture of blue and grey (Jaramillo and Burke 1999). (Howell and Webb, 1995; Jaramillo and Burke, 1999)
Immature individuals have duller yellow bodies and olive-black backs. The rump and uppertail coverts are also olive, but the wings are dark brown, the tail is olive yellow (Jaramillo and Burke 1999). (Jaramillo and Burke, 1999)
Juvenile yellow-tailed orioles have dull yellow and olive heads with pinkish lower mandibles. The back and rump are olive brown (Howell and Webb 1995). The wings are olive with two thin yellowish wingbars. Juveniles resemble immature individuals, but lack the black lores and black bib (Jaramillo and Burke 1999). (Howell and Webb, 1995; Jaramillo and Burke, 1999)
Subtle variations can be seen among yellow-tailed oriole subspecies. Icterus m. mesomelas individuals have secondary edgings and the base of the tertials edges are consistently yellow. Icterus m. carrikeri individuals have shorter bills and less black coloration on the throat than I. m. salvinii, but can be paler orange instead of yellow. Icterus m. salvinii individuals have larger bills than I. m. carrikeri and more extensive black on the throat. In comparison to I. m. carrikeri, I. m. mesomelas individuals are more orange in color. Finally, I. m. taczanowskii individuals are characterized by secondary edgings and white wing panel. They are more yellow than I. m. mesomelas (Jaramillo and Burke 1999). The closest relatives of yellow-tailed orioles are Icterus pectoralis and the complex that includes Icterus icterus (Omland et al. 1999). (Jaramillo and Burke, 1999; Omland, et al., 1999)
The male usually sings from the top of the trees whereas the female replies from the nest. The song is characterized by repetitive whistle-like sounds, varying in the number of notes (Jaramillo and Burke 1999). (Jaramillo and Burke, 1999)
Females build a nest of vegetable fiber in the shape of a basket which may hang two meters up in a shrub (Stiles and Skutch 1989). Clutch size is two to three eggs which are light blue with brown spots (Jaramillo and Burke 1999). Yellow-tailed orioles prefer to nest at low to mid-levels in shrubs or trees (Howell and Webb 1995). Nesting for this species happens later in the year than any other local orioles and differs depending on the location: in Panama nesting is in April, in Oaxaca, Mexico and Colombia nesting is in the middle of June. Nesting sometimes extends into November (Davis 1972). (Davis, 1972; Howell and Webb, 1995; Jaramillo and Burke, 1999; Stiles and Skutch, 1989)
A single hybrid between an I. mesomelas and I. chrysater from Colombia has been studied, and it was proposed that the lack of mates in the area may have led to this hybridization (Olson 1983). This hybridization is noteworthy because the two species are quite distantly related for orioles (Omland et al. 1999). (Olson, 1983; Omland, et al., 1999)
Nesting period and dependency on the parents differs across their range but, typically the incubation period last 14 days and the hatchling needs approximately 13 days of parental care in the nest (Jaramillo and Burke 1999). (Jaramillo and Burke, 1999)
There is no information on lifespan in the literature.
Yellow-tailed orioles are secretive orioles, although they are conspicuous when singing on exposed perches. Yellow-tailed orioles prefer living in pairs or forming small groups and can join flocks of other oriole species (Howell and Webb 1995). Because this species is non-migratory pairs are likely maintained year round (Friedman et al., 2009). (Friedman, et al., 2009; Howell and Webb, 1995)
Home range size is not reported in the literature. (Jaramillo and Burke, 1999)
The call of yellow-tailed orioles is a repeated nasal chew or cheuk and a harder chuk or chook. Duetting birds commonly perform rhythmic repetition of phrases (Howell and Webb, 1995). Duetting and elaborate female song is common in tropical orioles (Price et al., 2009). (Howell and Webb, 1995; Price, et al., 2009)
The diet of yellow-tailed orioles includes nectar and invertebrates, such as spiders (Stiles and Skutch 1989). Although they prefer dense undergrowth, they forage at all levels and have been seen on flowering trees (Restall et al. 2006). (Restall, et al., 2006; Stiles and Skutch, 1989)
There are no predators of yellow-tailed orioles reported in the literature.
Yellow-tailed orioles prefer areas of dense vegetation, including agricultural land, such as banana plantations (Jaramillo and Burke 1999). Yellow-tailed orioles can aid in pollination and seed dispersal. They also forage on insects and can potentially protect plants from pest insects. (Jaramillo and Burke, 1999)
Yellow-tailed orioles feed on insects in agricultural land and may contribute to the well-being of crops such as bananas. Like other tropical birds, their existence promotes ecotourism and birding, making a significance contribution to the local economy.
There are no known adverse affects of yellow-tailed orioles on humans, though they may feed on bananas and other fruit.
Because of their large range, which lacks significant fragmentation, and stable population sizes, yellow-tailed orioles are not considered vulnerable. They are considered a species of least concern by the IUCN. (Bird and Butchart, 2010)
Lucia Zegarra (author), University of Maryland, Baltimore County, Kevin Omland (editor), University of Maryland, Baltimore County, Tanya Dewey (editor), University of Michigan-Ann Arbor.
living in the southern part of the New World. In other words, Central and South America.
uses sound to communicate
living in landscapes dominated by human agriculture.
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.
Referring to an animal that lives in trees; tree-climbing.
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.
uses smells or other chemicals to communicate
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
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.
parental care is carried out by females
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).
Having one mate at a time.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
an animal that mainly eats all kinds of things, including plants and animals
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
uses touch to communicate
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
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Davis, I. 1972. A Field Guide to the Birds of Mexico and Central America. Austin: University of Texas Press.
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Ridgely, R., G. Tudor. 2001. The Birds of South America Volume 1 The Oscine Passerines Jays and Shallows Wrens, Thrushes, and Allies Vireos and Wood-warblers Tanagers, Icterids, and Finches. Austin: University of Texas Press.
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