Plain antvireo explained

The plain antvireo (Dysithamnus mentalis) is a passerine bird species in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds".[1] It is found in Mexico, every Central American country except El Salvador, on both Trinidad and Tobago, and in every mainland South American country except Chile, French Guiana, Suriname, and Uruguay.[2]

Taxonomy and systematics

The plain antvireo was described by the Dutch zoologist Coenraad Jacob Temminck in 1823 and given the binomial name Myothera mentalis.[3] [4] It is now placed in the genus Dysithamnus which was introduced by the German ornithologist Jean Cabanis in 1847.[5]

The plain antvireo has these 18 subspecies:[1]

Description

The plain antvireo is 10to long and weighs 12to. It is a rather chunky bird with a large head and short tail. Adult males of the nominate subspecies D. m. mentalis have a dark gray forehead and crown and blackish ear coverts. Their upperparts are grayish olive with a hidden white patch between the scapulars. Their wings are dark grayish olive with olive edges on the flight feathers, white tips on the grayish olive greater coverts, blackish median coverts with white tips, and blackish lesser coverts. Their tail is dark grayish olive with narrow white tips on the feathers. Their throat and upper breast are white with light gray spots and their sides olive gray. Their lower breast, flanks, and crissum are pale gray and the center of their belly yellow. Adult females have a cinnamon-tawny crown. Their upperparts and wings are more olive and less gray than the male's and they lack the white interscapular patch. Their wing coverts and the edges of their flight feathers are olive-yellow. Their underparts have more extensive yellow than do males'.[2] [6] [7]

The other subspecies of the plain antvireo differ from the nominate and each other thus:[2] [6] [8] [9] [10] [11] [12] [13]

There is some question about the validity of all the subspecies, with some possibly representing clinal variation rather than subspeciation. "[M]olecular studies [are] needed in order to establish relationships among populations."[2]

Distribution and habitat

The plain antvireo has an oddly shaped and disjunct distribution. The subspecies are found thus:[2] [6] [7] [8] [9] [10] [11] [12] [13] [14]

Subspecies D. m. andrei is known in Guyana in the Pakaraima Mountains (though not Mount Roraima) and the southern Acari Mountains; as of 2007 it had not been recorded in the Iwokrama Forest or the Potaro Plateau.[15]

The plain antvireo inhabits a variety of landscapes across its wide range. In Mexico and Central America it occurs in the understorey to mid-storey of humid montane evergreen forest and mature secondary forest. In the northern part of this area it ranges in elevation from sea level to 1500m (4,900feet) though mostly below 1250-2NaN-2, while in Costa Rica it reaches 2500m (8,200feet) though only rarely.[2] [8] [9] [10] [14] In the northern mountains and tepuis of Venezuela and in the Andes from Venezuela and Colombia to Bolivia it occurs in humid evergreen forest and also in semi-deciduous and deciduous forest and woodlands. In Colombia it ranges between 300and. In Ecuador west of the Andes it occurs from sea level to 1500m (4,900feet) and east of the Andes between 700and. In Peru it occurs between 400and and in Bolivia as high as 2500-2NaN-2.[2] [11] [12] [13] In northeastern Brazil subspecies emiliae inhabits dry forest in savanna and also in wetter terra firme and várzea forests. The nominate subspecies mentalis is mostly found in humid Atlantic Forest. Elsewhere in the east and south (i.e. eastern Venezuela, Guyana, inland Brazil, Paraguay, and Argentina) it occurs in dry savanna forest, mature secondary forest, gallery forest, and semi-deciduous forest as high as 2500m (8,200feet).[2] [6] [8]

Behavior

Movement

The plain antvireo is thought to be a year-round resident throughout its range.[2]

Feeding

The plain antvireo feeds mostly on insects; its diet also includes other arthropods like spiders and occasionally Rapanea mistletoe berries. It usually forages singly or in pairs, and often joins a mixed-species feeding flock though almost as often forages away from them. It typically feeds from near the ground to about 4or above it, occasionally higher and very rarely up to the forest subcanopy. It forages rather sluggishly, gleaning from a perch, and taking most of its prey from foliage though often from vines and sometimes thin branches and dead leaves. It sometimes sallies from a perch to hover-glean, and sometimes forages on the ground. It occasionally attends army ant swarms for a short period.[2] [6] [7] [8] [9] [10] [11] [12] [13] [16]

Breeding

The plain antvireo's nesting season varies geographically. It spans from February to July in Costa Rica, April to July in Trinidad, and includes November in southeastern Brazil and northern Argentina. Its season has not been detailed elsewhere. Its nest is a cup of fibers from roots, fungus, and green plants and often is covered with green moss; strands of moss often dangle below the cup. It is typically suspended from a branch fork in a shrub or small tree between about 0.6and above the ground. The clutch size is two eggs; both parents incubate during the day and usually only the female at night. The incubation period is about 15 days and (in Costa Rica) fledging occurs nine to 10 days after hatch.[2]

Breeding pairs are quite territorial against conspecifics, and in the Atlantic Forest defend a patch of habitat that may be as large as about 7000m2, but sometimes is only half that size.[17]

Vocalization

The plain antvireo's song is generally a "short...series starting with a few...evenly paced, countable notes at same pitch, notes then gradually becoming more abrupt and dropping in pitch, ending in accelerating roll".[2] Authors have described it as a "high nasal watje watjwatwaturururu sounding as a rattle"[8] and as "a nasal barking series...weu-weu-weu-Weu-Weu-Weu-Weu-Weu'weu'wru'weu'u'u'u"[9] . Its calls include a "nasal, musical note" and a "short...rapid series of gradually rising notes".[2]

Status

The IUCN has assessed the plain antvireo as being of Least Concern. It has an extremely large range and an estimated population of at least 500,000 mature individuals. The latter is believed to be decreasing. No immediate threats have been identified. It is considered generally fairly common, though uncommon in northern Central America, uncommon in the Costa Rican lowlands, and common in Colombia and western Ecuador.[2] [9] [10] [11] [12] It occurs in several protected areas though "continuing deforestation could ultimately threaten some races".[2] In southeastern Brazil it "appears to be adversely affected by selective logging".[2] [17]

Further reading

Notes and References

  1. Web site: Antbirds . IOC World Bird List . v 14.1 . Gill . Frank . Frank Gill (ornithologist) . Donsker . David . Rasmussen . Pamela . Pamela Rasmussen . January 2024 . 4 January 2024 .
  2. Zimmer, K. and M.L. Isler (2020). Plain Antvireo (Dysithamnus mentalis), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.plaant1.01 retrieved March 10, 2024
  3. Book: Temminck, Coenraad Jacob . Coenraad Jacob Temminck . 1838 . 1823 . Nouveau recueil de planches coloriées d'oiseaux, pour servir de suite et de complément aux planches enluminées de Buffon . 2 . Plate 179, Fig. 3 . F.G. Levrault . Paris . fr . The 5 volumes were originally issued in 102 parts, 1820-1839
  4. Book: Peters . James Lee . James L. Peters . 1951 . Check-list of Birds of the World . 7 . Museum of Comparative Zoology . Cambridge, Massachusetts . 184 .
  5. Cabanis . Jean . Jean Cabanis . 1847 . Ornithologische notizen . Archiv für Naturgeschichte . de . 13 . 186–256 [223] .
  6. Book: van Perlo, Ber. A Field Guide to the Birds of Brazil . Oxford University Press . 2009 . New York . 238–239 . 978-0-19-530155-7 .
  7. Book: de la Peña . Martín R. . Rumboll . Maurice. Birds of Southern South America and Antarctica . Princeton University Press . Princeton Illustrated Checklists . 2001 . New Jersey . plate 67, map 67.2 . 0691090351 .
  8. Book: vanPerlo, Ber . Birds of Mexico and Central America . Princeton University Press . Princeton Illustrated Checklists . 2006 . New Jersey . plate 59, map 59.14 . 0691120706 .
  9. Book: Fagan . Jesse . Komar . Oliver . Field Guide to Birds of Northern Central America . Houghton Mifflin Harcourt . Peterson Field Guides . 2016 . Boston . 228–229 . 978-0-544-37326-6 .
  10. Book: Garrigues . Richard . Dean . Robert . 2007 . The Birds of Costa Rica . Ithaca . Zona Tropical/Comstock/Cornell University Press . 180–181 . 978-0-8014-7373-9 .
  11. Book: McMullan . Miles . Donegan . Thomas M. . Quevedo . Alonso . Field Guide to the Birds of Colombia . Fundación ProAves. 2010 . Bogotá . 130 . 978-0-9827615-0-2 .
  12. Book: Ridgely . Robert S. . Greenfield . Paul J. . The Birds of Ecuador: Field Guide . Cornell University Press . II. 2001 . Ithaca . 399 . 978-0-8014-8721-7 .
  13. Schulenberg, T.S., D.F. Stotz, D.F. Lane, J.P. O’Neill, and T.A. Parker III. 2010. Birds of Peru. Revised and updated edition. Princeton University Press, Princeton, New Jersey plate 160
  14. Múnera-Roldán, Claudia; Cody, Martin L.; Schiele-Zavala, Robin H.; Sigel, Bryan J.; Woltmann, Stefan & Kjeldsen, Jørgen Peter (2007): New and noteworthy records of birds from south-eastern Nicaragua. Bulletin of the British Ornithologists' Club 127 (2): 152–161. PDF fulltext
  15. O'Shea, B.J.; Milensky, Christopher M.; Claramunt, Santiago; Schmidt, Brian K.; Gebhard, Christina A.; Schmitt, C. Gregory & Erskine, Kristine T. (2007): New records for Guyana, with description of the voice of Roraiman Nightjar Caprimulgus whitelyi. Bulletin of the British Ornithologists' Club 127 (2): 118–128.
  16. Machado, C. G. (1999): A composição dos bandos mistos de aves na Mata Atlântica da Serra de Paranapiacaba, no sudeste brasileiro [Mixed flocks of birds in Atlantic Rain Forest in Serra de Paranapiacaba, southeastern Brazil]. Revista Brasileira de Biologia 59 (1): 75–85 [Portuguese with English abstract]. PDF fulltext
  17. Duca, Charles; Guerra, Tadeu J. & Marini, Miguel Â. (2006): Territory size of three Antbirds (Aves, Passeriformes) in an Atlantic Forest fragment in southeastern Brazil. [English with Portuguese abstract] Revista Brasileira de Zoologia 23 (3): 692–698. PDF fulltext