Middle American Screech-Owl Megascops guatemalae Scientific name definitions

The Vermiculated Screech-Owl is a small, finely-marked owl of lowland and lower montane forest. It occurs in several disjunct populations, which are often divided into separate species. The M. g. "guatemalae" group occurs from Mexico south to Nicaragua, M. g. vermiculatus is found from Costa Rica to northern Colombia and northern Venezuela, M. g. roraimae occurs in the tepuis of southern Venezuela and northern Brazil, and M. g. napensis is found along eastern Andean slopes from Ecuador to Bolivia. Populations differ largely in vocal characters. All populations are often heard calling shortly after dusk, and can sometimes be spotlighted on perches at relatively low levels and in dense vegetation.

Middle American Screech-Owl (Middle American)

20–23 cm (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ); 95–150 g (2 Whitacre, D.F. ed. (2012). Neotropical Birds of Prey: Biology and Ecology of a Forest Raptor Community. Comstock, Ithaca, NY. Close ). Medium-sized Megascops; occurs in brown and rufous morphs . Brown morph with facial disc light brown and lightly barred white, with thin dark border; thin white eyebrows contrast with short dark ear tufts; indistinct pale nuchal collar; crown heavily spotted and barred blackish; upperparts relatively dark grey-brown to blackish-brown with darker vermiculations and streaks, scapulars with black-edged whitish outer webs; flight feathers and tail barred; paler below, with blackish shaft streaks and vermiculations, strongest on breast; tarsus fully feathered; irides yellow ; cere and bill greenish (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ); toes dusky-flesh (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ). Rufous morph less boldly patterned. Differs from M. vermiculatus in feathered lower tarsus, stronger markings. Juvenile similar to adult, faintly barred. Races differ in tone of colouration and in size, which increases from N to SE: cassini smallest (wing length 152–159 mm (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ) ) and darkest; hastatus intermediate in size (wing length 153–165 mm (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ) ); dacrysistactus similar in size to nominate (wing length 164–175 mm and 152–178 mm, respectively (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ) ) but paler.

Vermiculated Screech-owl (Megascops vermiculatus)

20–23 cm; 91–128 g (2 Whitacre, D.F. ed. (2012). Neotropical Birds of Prey: Biology and Ecology of a Forest Raptor Community. Comstock, Ithaca, NY. Close ). Occurs in brown and rufous morphs. Brown morph with facial disc light brown with thin dark rings, indistinct border, pale eyebrows obscure; greyish-brown to buffy-brown above, finely and uniformly vermiculated with black; scapulars with white outer webs; flight-feathers prominently barred; whitish below , densely and finely vermiculated with black and brown , with some dark shaft streaks; tarsus feathered almost to toes; irides deep yellow ; bill grey-green; toes pinkish-grey. Rufous morph bright uniform rufous above and on head. Distinguished from M. guatemalae by bare lower tarsus, less strongly patterned plumage. Juvenile dull buffy-brown, abdomen and flanks with down feathers tipped greyish-white. Race roraimae darker, more heavily patterned; <em>napensis</em> with distinct white eyebrows, sometimes (seldom?) brown eyes (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ).

Editor's Note: This article requires further editing work to merge existing content into the appropriate Subspecies sections. Please bear with us while this update takes place.

Middle American Screech-Owl (Middle American)

Perhaps a member of the putative species-group centred on M. atricapilla (which see). Sometimes considered conspecific with M. atricapilla; has been treated as conspecific with M. vermiculatus (with races roraimae and napensis), but vocally distinct. Races tomlini, fuscus and thompsoni possibly inadequately differentiated to merit subspecific status and are not recognized in two recent treatments (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close , 3 Mikkola, H. (2014). Owls of the World. A Photographic Guide. 2nd edition. Firefly Books, Buffalo, NY, USA. Close ). Proposed races pettingilli and peteni included in cassini and nominate, respectively. Seven subspecies recognized.

Vermiculated Screech-owl (Megascops vermiculatus)

Perhaps a member of the putative species-group centred on M. atricapilla (which see). Sometimes considered conspecific with M. guatemalae, but vocally distinct. Isolated races roraimae and napensis may constitute two separate species; a recent treatment as such (4 König, C., F. Weick, and J.-H. Becking (1999). Owls. A Guide to the Owls of the World. Pica Press, Robertsbridge, UK. Close , 1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ), however, failed to provide comparisons involving all three taxa, so that claimed morphological and vocal distinctiveness of each is impossible to judge. Additional forms described from Peru (helleri) and Bolivia (bolivianus) here merged with napensis, but may merit subspecific recognition. Form centralis, here included in nominate vermiculatus, is sometimes recognized as separate species (range Panama to SW Ecuador) “based primarily on its distinctive voice” (5 Ridgely, R. S., and P. J. Greenfield (2001). The Birds of Ecuador. Volumes 1 and 2. Cornell University Press, Ithaca, NY, USA. Close ); further investigation needed. Form inexpectus (Costa Rica) included in nominate. Three subspecies recognized.

Editor's Note: Additional distribution information for this taxon can be found in the 'Subspecies' article above. In the future we will develop a range-wide distribution article.

Middle American Screech-Owl (Middle American)

Humid lowland to semi-arid evergreen forest, semi-deciduous forest and thorn forest; also dense second growth and similar scrubby woodlands (6 Howell, S. N. G., and S. Webb (1995). A Guide to the Birds of Mexico and Northern Central America. Oxford University Press, New York, NY, USA. Close ) and plantations. From sea-level to 1500 m elevation (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ).

Vermiculated Screech-owl (Megascops vermiculatus)

Humid tropical forest in lowlands and foothills, to c. 1200 m. Race roraimae inhabits rainforest on mountain slopes, at 1000–1800 m; <em>napensis</em> mostly above 250 m, up to 1500 m.

Middle American Screech-Owl (Middle American)

Presumably resident (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ).

Vermiculated Screech-owl (Megascops vermiculatus)

Middle American Screech-Owl (Middle American)

Mainly large insects such as beetles, katydids, orthopterans; frogs, reptiles, fish and small rodents occasionally reported. Nocturnal hunter, using forest clearings and edge. Hunts from perch, swooping on to prey on ground or branch; also catches insects in flight (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ).

Vermiculated Screech-owl (Megascops vermiculatus)

Little information. Probably fees mainly large insects; perhaps also takes small vertebrates. Prey at one nest in W Ecuador included insects, a whip spider (Amblypygi), small frogs and unknown passerines (7 Reyes, E.M.R. and Astudillo-Sánchez, E. (2017). Notes on the nest, owlets, diet, and parasites of the Choco Screech-Owl (Megascops guatemalae centralis) in Loma Alta Communal Reserve, western Ecuador. Wilson Journal of Ornithology. 129(2): 377-381. Close ).

Middle American Screech-Owl (Middle American)

Primary territorial song a rapid, quavering trill  , c. 14 notes per second, increasing in pitch and volume, ending abruptly, usually 6–15 but up to 20 seconds in duration (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ); secondary song short series of notes, speeding up in bouncing-ball rhythm.

Vermiculated Screech-owl (Megascops vermiculatus)

Primary song very fast , long, toad-like trill , starting softly, becoming louder, then dropping in pitch and fading out towards end; female may answer with shorter, higher trill; probable secondary song a very brief descending purr; also “ghoor”  or “khooo” calls. Races roraimae and napensis similar to M. guatemalae, but song shorter.

Middle American Screech-Owl (Middle American)

Little published information. Reported to lay mostly Mar–Apr, but incubation recorded in Jun in Yucatán Peninsula; juveniles observed in Jun. Nest in natural tree cavity or old woodpecker hole; recorded in old nest of trogon (Trogon). Clutch size 2–3 eggs (1 König, C., F. Weick, and J.-H. Becking (2008). Owls of the World. Second Edition. Christopher Helm, London, UK. Close ) (occasionally up to 5?); apparently no data on length of incubation and nestling periods.

Vermiculated Screech-owl (Megascops vermiculatus)

Very poorly known. Said to lay during Mar in N of range. Nest in natural tree cavity or old nest hole of other bird. Clutch size reported to be 3 eggs. Nest found in W Ecuador contained two nestlings on 7 Mar 2015; nest was in natural cavity of dead tree 3·35 m above ground; owlets fledged before 21 Mar, suggesting that egg laying occurred in Jan (7 Reyes, E.M.R. and Astudillo-Sánchez, E. (2017). Notes on the nest, owlets, diet, and parasites of the Choco Screech-Owl (Megascops guatemalae centralis) in Loma Alta Communal Reserve, western Ecuador. Wilson Journal of Ornithology. 129(2): 377-381. Close ). One nest found in SW Colombia with nestlings in Nov.

Middle American Screech-Owl (Middle American)

Not globally threatened (Least Concern). CITES II. Little information available, and no estimates of global population size; appears to be not rare locally. Has been recorded at San Blas (Nayarit), El Sumidero and Bonampak (Chiapas) and Cobá and Felipe Carrillo Puerto (Quintana Roo). Populations have probably declined as a result of forest destruction. Habitat loss a threat, at least in long term.

Vermiculated Screech-owl (Megascops vermiculatus)

Not globally threatened (Least Concern). CITES II. Needs almost solid forest. Very little information; possibly not rare locally. Has been recorded at Finca La Selva, on the Caribbean lowlands of Costa Rica, and the Pipeline road, in central Panama. Forest destruction a threat, at least in long term.