Oriole blackbird

The oriole blackbird (Gymnomystax mexicanus) is a species of bird in the family Icteridae. Its genus, Gymnomystax, is monotypic.[2] It is a medium-sized yellow and black bird found in Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, and Venezuela, where its natural habitats are subtropical or tropical moist lowland forest, subtropical or tropical moist shrubland, subtropical or tropical seasonally wet or flooded lowland grassland, and swamps.[1]

Oriole blackbird
In Peru
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Icteridae
Genus:	Gymnomystax L. Reichenbach, 1850
Species:	G. mexicanus
Binomial name
Gymnomystax mexicanus (Linnaeus, 1766)
Synonyms
Oriolus mexicanus Linnaeus, 1766

Taxonomy

In 1760 the French zoologist Mathurin Jacques Brisson included a description of the oriole blackbird in his Ornithologie based on a specimen which he mistakenly believed had been collected in New Spain. He used the French name Le troupiale brun de la Nouvelle Espagne and the Latin Icterus Fuscus Novae Hispaniae.[3] Although Brisson coined Latin names, these do not conform to the binomial system and are not recognised by the International Commission on Zoological Nomenclature.[4] When in 1766 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the twelfth edition, he added 240 species that had been previously described by Brisson.[4] One of these was the oriole blackbird. Linnaeus included a brief description, coined the binomial name Oriolus mexicanus, cited Brisson's work and gave the type location as Mexico.[5] The type location was subsequently designated as Cayenne in French Guiana.[6] This species is now the only member of the genus Gymnomystax that was introduced by the German naturalist Ludwig Reichenbach in 1850.[7] The name Gymnomystax combines the Ancient Greek words gumnos "bare" and mustax "moustache".[8] The species is monotypic.[9]

Description

The oriole blackbird grows to a length of nearly 30 cm (12 in). The sexes are similar in appearance. The head, neck, shoulders and underparts are bright yellow; the back, wings, rump and tail are black, apart from the lower wing-coverts showing a strip of yellow. The eye is brown and is surrounded by a black eye ring, and the large bill and feet are blackish. The voice consists of several loud, scratchy calls, uttered from elevated perches or emitted when on the wing. One is a screech that resembles the sound made by a rusty hinge.[10]

Distribution and habitat

This icterid is found in the northern part of South America. Its range includes French Guiana, Guyana, Suriname, Venezuela, Colombia, Ecuador, Peru and northern Brazil.[1] Its typical habitat is grassy areas with isolated trees near rivers, marshes, islands in rivers and gallery forest.[11]

Ecology

The oriole blackbird is usually seen in pairs or small groups but does not form mixed species flocks. It perches in prominent positions on small trees or on the top of bushes and forages mostly on the ground, especially in muddy areas near water.[11] They feed on invertebrates such as earthworms, caterpillars and winged insects, as well as frogs and fruit, and sometimes tear open ripening maize cobs to feed on the seeds.[10]

Breeding takes place in May and June. The nest is a cup-shaped structure about 17 cm (7 in) in diameter, loosely woven out of dry grass and weed stems, and lined with rootlets. The eggs are pale blue with black, brown and lilac blotches and spots. The shiny cowbird, a brood parasite, sometimes lays its egg in an oriole blackbird's nest. The incubation period is about 18 days and the incubation is done solely by the female. Both parents join in feeding the chicks with small invertebrates and frogs which are not regurgitated but brought whole to the nest in the parent's beak.[10]

Status

G. mexicanus is a fairly common species and has a very extensive range. Its total population has not been estimated but its population trend seems to be steady. For these reasons, the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".[1]

References

1. BirdLife International (2012). "Gymnomystax mexicanus". IUCN Red List of Threatened Species. 2012. Retrieved 6 September 2015.CS1 maint: ref=harv (link)old-form url
2. "ITIS Report: Gymnomystax". Integrated Taxonomic Information System. Retrieved 10 August 2014.
3. Brisson, Mathurin Jacques (1760). Ornithologie, ou, Méthode contenant la division des oiseaux en ordres, sections, genres, especes & leurs variétés (in French and Latin). Volume 2. Paris: Jean-Baptiste Bauche. pp. 105–106. The two stars (**) at the start of the section indicates that Brisson based his description on the examination of a specimen.
4. Allen, J.A. (1910). "Collation of Brisson's genera of birds with those of Linnaeus". Bulletin of the American Museum of Natural History. 28: 317–335.
5. Linnaeus, Carl (1766). Systema naturae : per regna tria natura, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis (in Latin). Volume 1, Part 1 (12th ed.). Holmiae (Stockholm): Laurentii Salvii. p. 162.
6. Paynter, Raymond A. Jr, ed. (1968). Check-list of birds of the world. Volume 14. Cambridge, Massachusetts: Museum of Comparative Zoology. p. 166.
7. Reichenbach, Ludwig (1850). Avium Systema Naturale. Das natürliche System der Vögel. Dresden: Expedition der Vollständigsten Naturgeschichte. Plate 73.
8. Jobling, J.A. (2018). del Hoyo, J.; Elliott, A.; Sargatal, J.; Christie, D.A.; de Juana, E. (eds.). "Key to Scientific Names in Ornithology". Handbook of the Birds of the World Alive. Lynx Edicions. Retrieved 5 May 2018.
9. Gill, Frank; Donsker, David, eds. (2018). "Oropendolas, orioles, blackbirds". World Bird List Version 8.1. International Ornithologists' Union. Retrieved 5 May 2018.
10. Skutch, Alexander Frank (1996). Orioles, Blackbirds, and Their Kin: A Natural History. University of Arizona Press. pp. 85–74. ISBN 978-0-8165-1601-8.
11. Ridgely, Robert S.; Guy, Tudor (1989). The Birds of South America: Volume 1: The Oscine Passerines. University of Texas Press. p. 344. ISBN 978-0-292-70756-6.