The blue-black grassquit (Volatinia jacarina) is a small Neotropical bird in the tanager family, Thraupidae. It is the only member of the genus Volatinia. It is a common and widespread bird that breeds from southern Mexico through Central America, and South America as far as northern Chile, Argentina, and Paraguay, and in Trinidad and Tobago.[2] A male was also observed in Graham County, Arizona on July 15 and July 17, 2023.[3]
This species is sexually dimorphic; the male is glossy blue with some white under the wing. The female is brown above and pale buff with darker streaks below.
Taxonomy
The blue-black grassquit was described by the Swedish naturalist Carl Linnaeus in 1766 in the twelfth edition of his Systema Naturae under the binomial nameTanagra jacarina.[4] Linnaeus based his description on the "Jacarni" that was described in 1648 by the German naturalist Georg Marcgrave in his Historia Naturalis Brasiliae.[5][6] The type locality is eastern Brazil.[6] The specific epithet jacarina is derived from the Tupi language and was used for a type of finch.[7] The blue-black grassquit is now the only species placed in the genus Volatinia and was introduced in 1850 by the German naturalist Ludwig Reichenbach.[8][9] The genus name is a diminutive of the Latin volatus meaning "flying".[10]
Within the tanager family Thraupidae the blue-black grassquit is in the subfamily Tachyphoninae and is a member of a clade that contains the genera Conothraupis and Creurgops.[11][12]
The blue-black grassquit was formerly placed with the buntings in the subfamily Emberizinae rather than with the tanagers in Thraupinae within an expanded family Emberizidae.[6][11]
V. j. splendens (Vieillot, 1817) – Mexico to Colombia and east through Venezuela and the Guianas to the Amazon basin; also Trinidad, Tobago and Grenada
V. j. jacarina (Linnaeus, 1766) – southeast Peru to east Brazil and south to north Argentina
V. j. peruviensis (Peale, 1849) – west Ecuador, west Peru, and northwest Chile
Description
Adult blue-black grassquits are 10.2 cm (4.0 in) long and weigh 9.3 g (0.33 oz). They have a slender conical black bill. The male is glossy blue-black, with a black tail and wings; the white inner underwing is visible in flight or display. Female and immature birds have brown upperparts and dark-streaked buff underparts.
Behavior
Social monogamous, extra-pair fertilizations, intraspecific parasitism, and quasi-parasitism are commonly found.[13][14] During the breeding season, males defend small territories, about 13,0 - 72,5 m2, dominant males are normally lighter.[15] The male has a jumping display, often performed for long periods, which gives rise to the local name "johnny jump-up". This is accompanied by a persistent wheezing jweeee call,[16] jumping several times in a minute.[17] The extravagant display also has a cost of calling attention of the predator, thus displaying increased nest predation.[18] Predation is the main cause of breeding failure,[19] and predator vocalizations can cause an immune-related reaction to this species.[20] Nests are small cups of rootlets (diameter about 7.5 cm) found in herbaceous vegetation 10–50 cm high,[21] clustered at a landscape,[22] and placed preferably at high complex habitat spots.[23] Nests are built by both sexes.[19][24]
Blue-black grassquits will often form flocks when not breeding. They eat seeds, mostly on the ground.[25]
^Marcgrave, Georg (1648). Historia Naturalis Brasiliae (in Latin). Vol. Liber Quintus: Qui agit de Avibus. Lugdun and Batavorum (London and Leiden): Franciscum Hackium and Elzevirium. p. 210.
^ abcPaynter, Raymond A. Jr, ed. (1970). Check-List of Birds of the World. Vol. 13. Cambridge, Massachusetts: Museum of Comparative Zoology. p. 132.
^Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. p. 210. ISBN978-1-4081-2501-4.
^Burns, K.J.; Unitt, P.; Mason, N.A. (2016). "A genus-level classification of the family Thraupidae (Class Aves: Order Passeriformes)". Zootaxa. 4088 (3): 329–354. doi:10.11646/zootaxa.4088.3.2. PMID27394344.
^Manica, Lilian T.; Graves, Jeff A.; Podos, Jeffrey; Macedo, Regina H. (2016-12-01). "Multimodal flight display of a neotropical songbird predicts social pairing but not extrapair mating success". Behavioral Ecology and Sociobiology. 70 (12): 2039–2052. doi:10.1007/s00265-016-2208-x. ISSN0340-5443. S2CID40033522.
^Dias, Raphael Igor; Kuhlmann, Marcelo; Lourenço, Luciane R.; Macedo, Regina H. (2009-11-01). "Territorial Clustering in the Blue-Black Grassquit: Reproductive Strategy in Response to Habitat and Food Requirements?". The Condor. 111 (4): 706–714. doi:10.1525/cond.2009.090142. ISSN0010-5422. S2CID84877861.
^Aguilar, Thais M.; Dias, Raphael I.; Oliveira, Ailton C.; Macedo, Regina H. (2008-03-01). "Nest-site selection by Blue-black Grassquits in a Neotropical savanna: do choices influence nest success?". Journal of Field Ornithology. 79 (1): 24–31. doi:10.1111/j.1557-9263.2008.00142.x. ISSN1557-9263.
^Ridgely, Robert S.; Tudor, Guy (2009). Birds of South America: Passerines. Helm Field Guides. London: Christopher Helm. p. 630. ISBN978-1-408-11342-4.