Puerto Rican owl

Puerto Rican owl
	Gymnasio nudipes over a Delonix regia tree
	Gymnasio nudipes newtoni
Conservation status
	; Least Concern (IUCN 3.1)
	CITES Appendix II (CITES)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Strigiformes
Family:	Strigidae
Genus:	Gymnasio; Bonaparte, 1854
Species:	G. nudipes
Binomial name
	Gymnasio nudipes; (Daudin, 1800)
Subspecies
	G. n. nudipes; G. n. newtoni

The Puerto Rican owl (Gymnasio nudipes) or múcaro común (Spanish via Taino), formerly known as the Puerto Rican screech owl, is a mid-sized "typical owl" in subfamily Striginae. It is endemic to the archipelago of Puerto Rico though it formerly also inhabited the Virgin Islands.^[3]^[4]^[5]

Taxonomy and systematics

The Puerto Rican owl was formally described in 1800 by the French zoologist François Marie Daudin from specimens collected in Puerto Rico. He coined the binomial name Strix nudipes.^[6] The species was subsequently placed either in the genus Otus with the scops owls^[7] or in Megascops with the screech owls. It is now the only species assigned to the genus Gymnasio that was introduced in 1854 specifically for the Puerto Rican owl by Charles Lucien Bonaparte.^[8]^[9]^[10] The genus name combines the Ancient Greek gumnos meaning "bare" or "naked" with the Latin asio, a type of eared owl. The specific epithet nudipes is Latin meaning "bare-footed".^[11]

A species endemic to the Virgin Islands was described in 1860 by George Newbold Lawrence under the binomial Gymnoglaux newtoni.^[12] This is treated as a subspecies of the Puerto Rican owl (Gymnasio nudipes newtoni), but its identity as a separate subspecies has been questioned because it is based on minor differences in plumage. The taxon is probably extinct as surveys of the Virgin Islands conducted since 1995 have failed to detect any Puerto Rican owls.^[13]^[14]^[5]

A molecular phylogenetic study of the owls published in 2019 found that the Puerto Rican owl is a sister species to the flammulated owl (Psiloscops flammeolus), a migratory species in North America.^[15]

Description

The Puerto Rican owl is 20 to 25 cm (7.9 to 9.8 in) long with a wing length of 154 to 171 mm (6.1 to 6.7 in). It weighs 100 to 170 g (3.5 to 6.0 oz), with females being slightly heavier than males. It has a rounded head with no "ear" tufts. It has three color morphs; the brown one predominates, the rufous one is fairly common, and the gray one is rare. The brown morph has brown upperparts with irregular paler brown bars and vermiculation. The tail is also brown with paler vermiculation. The wing coverts have some whitish spots. Its facial discs have narrow light and dark brown bars; the supercilium and lores are white. The underparts are mostly white with much brown or dusky streaking, barring, and vermiculation. The belly and undertail coverts are usually plain white. The legs are not feathered, which is unusual in owls, and led to another former common name, the Puerto Rican bare-legged owl. The eye is brown, the bill greenish yellow, and the legs and feet pale brown to grayish yellow. The rufous morph replaces the brown with pale reddish brown or ochre buff. Putative subspecies G. n. newtoni has somewhat paler upperparts and less heavily streaked underparts than the nominate.^[5]^[16]

Distribution and habitat

The Puerto Rican owl is found throughout the main island of Puerto Rico. The putative subspecies G. n. newtoni certainly occurred on St. Croix, St. John, and St. Thomas in the Virgin Islands but has not been positively recorded there since the mid 1800s. It possibly occurred on other Virgin Islands and on Vieques and Culebra, but no documentation supports those assertions. On Puerto Rico its primary natural habitat is humid lowland forest but it also occurs in dry forest and urban areas. "Any small territory with available nest cavities is ideal for this species."^[5]

Behavior

Movement

The Puerto Rican owl is resident throughout its range.^[5]

Feeding

The Puerto Rican owl is a nocturnal hunter. Its primary prey is large arthropods such as cockroaches, grasshoppers, and moths. It also regularly eats small vertebrates such as frogs, lizards, rodents, and birds.^[5]

Breeding

The Puerto Rican owl's breeding season spans from April to June. It nests in cavities in trees and lays a clutch of up to three white eggs. Little else is known about its breeding phenology.^[5]^[16]

Songs and calls

Listen to Puerto Rican owl on xeno-canto

Vocalization

The Puerto Rican owl's territorial song is "a short, relatively deep, somewhat guttural, toad-like quavering trill...rrurrrrrrr." It also makes "a soft cackling gu-gu and "a loud coo-coo"; the latter call provides the local colloquial name "cuckoo bird".^[5]

Status

The IUCN has assessed the Puerto Rican owl as being of Least Concern. Though it has a relatively small range, its population exceeds 10,000 mature individuals and is believed to be stable. No specific threats have been identified.^[1] Its disappearance from the Virgin Islands is thought to have happened because the native forests there were mostly cleared by the end of the nineteenth century.^[5]

Gallery

An adult at the western municipality of Aguada
An owlet

References

^ ^a ^b BirdLife International (2016). "Puerto Rican Screech-owl Megascops nudipes". IUCN Red List of Threatened Species. 2016. Retrieved 9 March 2022.
^ "Appendices | CITES". cites.org. Retrieved 2022-01-14.
^ Gill, F.; Donsker, D.; Rasmussen, P., eds. (January 2022). "Owls". IOC World Bird List. v 12.1. Retrieved January 15, 2022.
^ HBW and BirdLife International (2020) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world Version 5. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v5_Dec20.zip [.xls zipped 1 MB] retrieved 27 May 2021
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Goodson, C. (2021). Puerto Rican Owl (Gymnasio nudipes), version 1.1. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.prsowl.01.1 retrieved March 9, 2022
^ Daudin, François Marie (1800). Traité élémentaire et complet d'ornithologie, ou, Histoire naturelle des oiseaux (in French). Vol. 2. Paris: Chez L'Auteur. p. 199.
^ Peters, James Lee, ed. (1940). Check-List of Birds of the World. Vol. 4. Cambridge, Massachusetts: Harvard University Press. p. 107.
^ Bonaparte, Charles Lucien (1854). "Tableau des oiseaux de proie". Revue et Magasin de Zoologie Pure et Appliquée. 2nd (in French). 6: 530–544 [543].
^ Chesser, R.T.; Billerman, S.M.; Burns, K.J.; Cicero, C.; Dunn, J.L.; Kratter, A.W.; Lovette, I.J.; Mason, N.A.; Rasmussen, P.C.; Remsen, J.V.J.; Stotz, D.F.; Winker, K. (2020). "Sixty-first Supplement to the American Ornithological Society's Check-list of North American Birds". The Auk. 137 (ukaa030). doi:10.1093/auk/ukaa030.
^ Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (January 2021). "Owls". IOC World Bird List Version 11.1. International Ornithologists' Union. Retrieved 21 May 2021.
^ Jobling, James A. (2010). The Helm Dictionary of Scientific Bird Names. London: Christopher Helm. pp. 182, 276. ISBN 978-1-4081-2501-4.
^ Lawrence, George Newbold (1860). "Notes on some Cuban birds, with descriptions of new species". Annals of the Lyceum of Natural History of New York. 7: 247-275 [259].
^ Pardieck, Keith; Myers, J; Pagan, Michelle (1996). "Surveys of Puerto Rican screech-owl populations in large-tract and fragmented forest habitats" (PDF). The Wilson Bulletin. 108 (4): 776–782. JSTOR 4163757.
^ Moreno, Jorge A. (1998). "Status of the Virgin Islands screech-owl" (PDF). Journal of Field Ornithology. 69 (4): 557–562. JSTOR 4514360.
^ Salter, J.F.; Oliveros, C.H.; Hosner, P.A.; Manthey, J.D.; Robbins, M.B.; Moyle, R.G.; Brumfield, R.T.; Faircloth, B.C. (2019). "Extensive paraphyly in the typical owl family (Strigidae)". The Auk. 137 (ukz070). doi:10.1093/auk/ukz070. hdl:2346/93048.
^ ^a ^b Deane Lewis (October 20, 2020). "Puerto Rican Screech Owl ~ Megascops nudipes". Retrieved March 9, 2022.