j Raptor Res. 27(3):154-160 ¸ 1993 The Raptor ResearchFoundation, Inc.

PRESENCE AND DISTRIBUTION OF MEXICAN : A REVIEW

PAULA ENRiQUEZ-ROCHA GEB-Mex, Ap. Postal4-077, 06400 M•xico, D.F., M•xico

j. Luis RANGEL-SALAZAR Departamentode EcologœaTerrestre, CIQRO, Ap. Postal424, 7700 Chetumal,Quintana Roo, Mdxico

DENVER W. HOLT OzolResearch Institute, P.O. Box 8335, Missoula, MT 59807 U.S.A.

ABSTR^CT.--Mexicohas a rich assemblage,represented by 27 species.Eighteen of thesespecies occur in theNearctic and Neotropical regions, and nine species occur only in theNeotropical region. Their biology, ecologyand distribution,however, are poorly known. We recorded3683 specimenscollected between 1840 and 1991 from 11 nationaland 37 foreignmuseums, and reviewedthe literature concerningthese owls.From thesedata we presenta more unifieddistribution of Mexican owls.Four species,Barn Owl (Tyro alba), Great Horned Owl (Bubovirginianus), Ferruginous Pygmy-Owl (Glaucidiumbrasilianum) and Burrowing Owl (Speotytocunicularia), have a wide distribution. The Balsas ScreechOwl (Otus seductus)is endemicto the centralPacific region. Oaxaca and Michoacanhad the highestowl species richnesswith 21 and 19 species,respectively. Aguascalientes, Campeche and Tlaxcala had the lowest owl speciesrichness, four, five, and five respectively.The FerruginousPygmy-Owl was the mostcollected owl, representing30.7% of the specimens,and the UnspottedSaw-whet Owl (Aegoliusridgwayi) the least with 0.19%.Of the Neotropicalspecies, the UnspottedSaw-whet Owl, StripedOwl (Asioclamator), and StygianOwl (A. stygius)are consideredendangered by the Mexicangovernment. The screech-owlgroup (Otus)and the ( varia)/FulvousOwl (S. fulvescens-- S. v. fulvescens)have uncertain distributions due to taxonomic uncertainties.

Presenciay distribuci6nde los bfihosMexicanas: una revisi6n RESUMEN.--M•xicotiene una alta riquezade especiesde bfihos,representada pot 27 especies.Dieciocho de estasespecies se encuentran tanto en la regionneirtica comoen la neotropical,y nuevede las especies selocalizan solo en la regi6nneotropical. Su biologla,ecologla asl comosu distribuci6nes poco conocida. Nosotroscompriamos 3683 datosde especlmenesde bfihoscolectados en Mgxico;con registros desde 1840 hasta 1991, de 11 museosnacionales y de 37 extranjeros,adicionalmente revisamos intensamente la literatura disponible.Combinando estos datos, damos una distribuci6nunificada de los bfihosde Mgxico. Cuatroespecies, la Lechuzade Campanario(Tyto alba), el BfihoCornado Americano (Bubo virginianus), el TecolotitoBajefio (Glaucidium brasilianum) y el TecoloteZanc6n (Speotytocunicularia) tienen una amplia distribuci6nen el continenteAmericano. E1 TecoloteOjioscuro del Balsas(Otus seductus) es endgmicopara la regi6ndel PacificoCentral de Mgxico.Los estados de mayor riqueza de especies fueron Oaxacay Michoacincon 21 y 19 especiesrespectivamente, por el contrariolos estados con menor riqueza fueronAguascalientes, Campeche y Tlaxcalacon 4, 5 y 5 respectivamente.El TecolotitoBajefio ha sido la especiede bfihomils colectada, representando el 30.7% de los especlmenes, y el queregistro con menos colectasfug el TecoloteAbetero Surerio (Aegolius ridgwayi) representando tan solo el 0.19%.De lasespecies neotropicales,el TecoloteAbetero Surerio, el BfihoCornado Cariblanco (Asio clamator) y el BfihoCornado Oscuro(A. stygius)son consideradas como amenazadas por el gobiernoMexicano. E1 grupoOtus asi comoel BfihoSerrano Vientrirrayado (Strix varia)/Bfiho Serrano Surerio (S. fulvescens = S. v.fulvescens) tienen distribuciones controversiales debidas a su clasificaci6n incierta. [Traducci6n Autores]

Currently, there are 178 speciesof owls recog- forests,north of 35ø (Norberg 1987). Although,there nized in the world (Sibley and Alhquist 1990), of is someoverlap. which 27 (15%) speciesoccur in . This ex- Owls in Mexico have been little studied and most ceedsthe owl speciesdiversity (N = 22) of northern literature is old (Ridgway 1895, Kelso and Kelso

154 SEPTEMBER 1993 MEXICAN OWL DISTRIBUTION 155

Sonora

Chihuahua aa Coahuila Californi,

Sur Si Durango

dipas 1. Aguascalientes 2. OistritoFederal •,,N• Gulf of 3. Guanajuato Mexico

4.5. MorelosHidalgo • IRa 6. Queretaro Colinn :ruz 7. Tlaxcala Guerrero

Pacific Ocean Oaxaca

Figure 1. Map of the Mexican Republic showinglocations of 32 states.

1936, Moore 1937a, 1937b, 1941, 1947a, Moore choacfin,Escuela Nacional de CienciasBio16gicas, Insti- and Peters 1939, Alvarez del Toro 1949, Briggs tuto de Historia Natural de Chiapas, Instituto Nacional 1954, Moore and Marshall 1959, Buchanan 1964, de InvestigacionesForestales y Agropecuarias-Bacalar, Instituto Nacional de Investigacionessobre Recursos B•6- Northern 1965). Generally,most Mexican owl spe- ticos,Laboratorio Natural de Las Joyas, Universidad de cieshave limited morphologicaldescriptions and only Guadalajara, Museo de Zoologlade la Facultad de Cien- approximateddistributions (Friedman et al. 1950, cias, Museo de Zoologla Iztacala, Sa16nde las Aves de Blake 1972, Davis 1972, Peterson and Chalif 1973, Saltillo Coahuila,Universidad Aut6noma de Baja Cali- fornia Sur and 37 foreignmuseums (Australian Museum, 1989, Edwards 1989). Unfortunately,these distri- AnnistonMuseum of Natural History, Academyof Nat- butionsare often controversial.Here, we presenta ural Sciencesof Philadelphia,Bell Museum of Natural review of the distribution and relative status of Mex- History, British Museum, Carnegie Museum of Natural ican owls based on museum specimen data and History, Cornell University Collection,Collection Zool- available literature. ogy Museum Amsterdam-Nederland, Denver Museum of Natural History, Delaware Museumof Natural History, Fort Hays Museum,Florida Museumof Natural History, STUDY AREA AND METHODS Forschungsinstitutund Naturmuseum Senckenberg, Har- Mexico (2 million km2) has32 states(Fig. 1) with > 50% vard Museumof ComparativeZoology, Illinois StateMu- of the land mass above 1000 m elevation (Ramos 1985). seum Collection,Kansas University Collection,Los An- Its 32 vegetationtypes (Rzedowski 1986), geographiclo- gelesCalifornia Museum-Natural History, LouisianaState cation, and topography contribute to a rich diversity of UniversityMuseum Zoology,Moore Laboratoryof Zo- fauna and flora. ology-OccidentalCollege, Museo Nacional de Ciencias To obtain information on Mexican owl specimenswe Naturales-Espafia,Museum of Natural History-Chica- wrote letters to or visited 11 national museums (Colecci6n go, Museum of Vertebrate Zoology-Universityof Cali- Ornitol6gicadel Instituto de Biologla,Colecci6n Ornito- forniaBerkeley, Oklahoma Museum of Natural History, 16gicade San Nicol•tsde Hidalgo, Universidadde Mi- ProvincialMuseum of Alberta, PeabodyMuseum Col- 156 ENRiQUEZ-ROGHAET AL. VOL. 27, NO. 3 lection-YaleUniversity, Royal Ontario Museum, Rijks- museumVan Naturvlijke Historie-Leiden, SantaBarbara MuseumofNatural History, Southwestern College Col- Sr^TESø• lection,San Diego Museum of Natural History, Staatli- 0 O0 0 0 0 0 0 XO O0 O0 chesMuseum ftir Naturkundein Stuttgart,Texas Co- Bcs 0 O0 0 XO O0 O0 operativeWildlife Collection,National Museum of Natural 0 X 0 0 0 History-SmithsonianInstitute, University of Washington, c.,. O0 O0 0 O0 O0 OOOX 000 Thomas Burke Memorial State Museum, Universityof c.•s 0 0000000000 0 O0 0 OOX WisconsinZoological Museum, Western Foundation Ver- co^ O0 O0 0 O0 XOO0 O0 cot 0 0 000 0 O0 OXXOOO0 tebrate Zoology Collection,Zoological Institute of the 0 O0 0 0 0 OXO XO 0 X Academyof Sciences-URSS).Additionally, we reviewed OF O0 O0 0 0 0 XOO0 O0 the existingliterature for informationconcerning Mexican O0 0 XO 0 0 O0 0 0 0000 000 owls. For vegetationtypes, we followedRzedowski (1986). 0 0 0 0 000 O0 State boundarieswere the unit usedto delineatedistri- XO O0 X 0 0 0 O0 O0 O0 0 0 O0 000 O0 OX 000 butionsof the owls. We applied the taxonomyused by O0 0 O0 O0 X 0 OXO0 XO Amadonand Bull (1988) for mostof the owl specieswhich O0 O0 000 0 O0 000 XOOO0 O0 occurin Mexico. We followed Marshall et al. (1991) for •oR O0 0 O0 0 00000 0 0 0 0 O0 0 0000 recentchanges of VermiculatedScreech-Owl (Otus gua- OX O0 0 O0 O0 OOX 0 temalae)to Variable Screech-Owl(O. atricapillus),and o•x O0 0 O0 0000000 0 O0 OOXO X A.O.U. (1991) for genericchange of the BurrowingOwl O0 X O0 XO0 0000 X from Atheneto Speotyto.We includedthe Fulvous Owl 0 OX 0 0 0 0 O0 X 0 0 000 0 X 0 X (Strixfulvescens) as a subspeciesof the BarredOwl (Strix o•oo O0 O0 0 0 O0 0 0000 0 varia) = S. v.fulvescens (Edwards 1989, J. Marshall pers. O0 0 0 OOOOXO O0 0 O0 comm.). son O0 O0 0 0 O0 O0 0000 0 TAB 0 XO XO O0 0 RESULTS •^• 0 O0 0 0 O0 000XO 0 0 TLAX O0 0 0 0 We compiledand analyzeddata on 3683 speci- O0 0 0000000 0 O0 OX OOXX 0 0 O0 0 0 X X mensof Mexicanowls. Twenty-seven Mexican owl Yuc 0 0 0 0 000 speciesfrom boththe Nearcticand Neotropicalzoo- geographicregions are represented.Eighteen species Figure 2. Presenceof owl speciesby state in Mexico. occurin the Nearcticand Neotropicalregions, while Codesare describedin the text. (O = museum recordsand nine speciesoccur only in the Neotropicalregion. X = literature records.) The Balsas Screech-Owl (Otus seductus)is endemic to Mexico's Pacific slope region. The Bearded sula. Blake (1972) and Grossmanand Hamlet (1988) Screech-Owl(Otus barbarus)and UnspottedSaw- consideredthem widely distributed throughout whet Owl (Aegoliusridgwayi) are found only in Mexico. Chiapas. The greatestnumber of museumspecimens were Flammulated Owl (OFLA) Otusfiamrneolus of the FerruginousPygmy-Owl (Glaucidiumbrasi- Flammulated Owl inhabits highlandsand pine hanum) and least number of the UnspottedSaw- forestfrom 2100-3000 m elevation.It is migratory whet Owl. The richestowl assemblagecame from in southern Sinaloa, central Mexico and south Oaxaca and Michoacan with 21 and 19 species, throughthe highlandsof Chiapas.Eighty-one spec- respectively. imens from 16 stateswere recorded(Fig. 2). Ad- ditionally, it has beenreported for Distrito Federal SpeciesAccounts (Ridõway 1914, Friedman et al. 1950, Blake 1972) and Nuevo Le6n (A.O.U. 1983, Contreras-Balderas Barn Owl (TALB) Tyroalba 1992). The most widely distributedowl in Mexico, it inhabitatsforest, open areas, villages and cities,and Eastern Screech-Owl (OASI) Otus asio islands from sea level to 3500 m in elevation. One Eastern Screech-Owlinhabits pine forest, pine- hundred forty-one specimensfrom 31 stateswere oak forest and riparian from sea level to recorded(Fig. 2). Friedman et al. (1950) also re- 1500 m elevation.One hundredand sevenspecimens portedBarn Owls from Hidalgo and QuintanaRoo, from 19 stateswere recorded(Fig. 2). Its distribution as have we (Enrlquez-Rochaand Rangel-Salazar is restricted to northeastern and southern Mexico, pers. ohs.). Paynter (1955) and Hartiõ (1979) did which agreeswith Marshall (1967) and Rowley not report the Barn Owl from the Yucatan Penin- (1984). SEPTEMBER1993 MEXICAN OWL DISTRIBUTION 157

Western Screech-Owl (OKEN) Otuskennicottii elevation.One hundredand six specimensfrom 16 Western Screech-Owl inhabits dense pine and stateswere recorded (Fig. 2). Althoughreported from pine-oakforests, open habitats, and semi-desertveg- Campeche and Tabasco (Friedman et al. 1950, etation from 0-2400 m elevation. One hundred and Paynter 1955, Storer 1961, Davis 1972), no speci- forty-eight specimensfrom 15 stateswere recorded menswere located.This is the only speciesfrom the (Fig. 2). There is confusionregarding species and Otusgenus found in the Yucatan Peninsula. subspeciesdistributions due to taxonomicchanges (Marshall 1967). Our data conflictwith Blake (1972) CrestedOwl (LCRI) Lophostrixcristata who reportedthis speciesin Queretaroand Hidalgo. Crested Owl occurs in southern Mexico and in- Its distribution is northcentral, southwestern, and habitstropical evergreen and semi-deciduousforest, Baja California. riparian areas, partial clearings, and foothills. It rangesfrom sealevel to 1000 m elevation.Twenty- Balsas Screech-Owl (OSED) Otus seductus two specimensfrom four stateswere recorded(Fig. BalsasScreech-Owl inhabits tropical deciduous 2). Grossmanand Hamlet (1988) reportedit from forestand arid tropical scrub,and the edgesof crop- the Yucatan Peninsula, but we could not confirm land. It rangesfrom sea level to 1200 m elevation. this. Twenty-five specimensfrom two states were re- corded(Fig. 2). It hasalso been recorded in Guerrero SpectacledOwl (PPER) Pulsatrixperspicillata (Marshall 1967, Peterson and Chalif 1975, A.O.U. SpectacledOwl inhabitstropical evergreenand 1983). This, the only endemicMexican owl, is cur- semi-deciduousforests, riparian areas,partial clear- rently found only in Michoacan and Colima. ings, and forest edges.It rangesfrom sea level to 900 m. Thirty-one specimensfrom three stateswere PacificScreech-Owl (OCOO) Otuscooperi recorded(Fig. 2). It appearsrestricted to southern Pacific Screech-Owl inhabits tropical lowlands, Mexico, but Grossmanand Hamlet (1988) report mangroves,open forests,palm groves,and swamps. it for the Yucatan Peninsula. We are uncertain of It occursfrom sealevel to 90 m elevation.Twenty- this. three specimensfrom six stateswere recorded(Fig. 2). It appearsto exist only along the Pacific slope Great Horned Owl (BVIR) Bubovirginianus in southwestern Mexico. Great Horned Owl inhabitsa wide diversityof habitatsfrom forestland to open areas.It ranges WhiskeredScreech-Owl (OTRI) Otustrichopsis from sea level to 2700 m elevation. Two hundred Whiskered Screech-Owl inhabits highlands, in thirty-six specimensfrom 26 states were recorded pine-oakforest, pine forest and dry oak. It ranges from 1200-5000 m elevation. One hundred and (Fig. 2). Brodkorb(1943) reportedit for Tabasco, but no specimensexist. The presentdistribution en- ninety-threespecimens from 20 stateswere recorded compassesalmost the entire countryand its presence (Fig. 2). Additionally, it has been reported from in Tabascoseems likely. Hidalgo and Puebla (Davis 1972, A.O.U. 1985). It has a wide distribution but is absent in the Yucatan (CVIR) Ciccabavirgata and Baja California peninsulas. Mottled Owl inhabitstropical lowland forest, open tropicalforest, and foothills.It rangesfrom sealevel Bearded Screech-Owl (OBAR) Otusbarbarus to 2100 m elevation.Four hundred and one speci- BeardedScreech-Owl inhabits pine and pine-oak mensfrom 22 stateswere recorded(Fig. 2). It has forestfrom 1400-1800 m elevation.Only nine spec- a wide distribution,but is notyet reportedfrom Baja imens,all from Chiapas,were recorded(Fig. 2), but Peninsula and northcentral Mexico. Ridgway (1914) reportedit southof Chiapasin the highlandsof . It has the most restricted Black and White Owl (CNIG) distributionof any Mexican owl. Ciccabanigrolineata Black and White Owl appearsto have discontin- Vermiculated Screech-Owl (OGUA) uousdistribution within Mexico. It inhabitstropical Otusguatemalae evergreenand semi-deciduousforests, forest edge, or VermiculatedScreech-Owl inhabits riparian ar- partial clearings.It rangesfrom sealevel to 1200 m eas, tropical semi-deciduousand deciduousforests, elevation.Forty-six specimensfrom five stateswere and forestedges. It rangesfrom sealevel to 1500 m recorded(Fig. 2). Our museumdata agreewith the 158 ENRiQUEZ-ROCHAET AL. VOL. 27, No. 3 literature (Ridgway 1914, Friedman et al. 1950, not been reported from Mexico's peninsulasor the Blake 1972, Davis 1972, Petersonand Chalif 1973, northcentraland central plateaus. A.O.U. 1983, Edwards 1989). Paynter (1955) re- FerruginousPygmy-Owl (GBRA) portedone specimenfrom Quintana Roo, and we Glaucidium brasilianum have additional specimensfrom there. FerruginousPygmy-Owl inhabitslowland ripar- Barred Owl (SVAR) Strix varia ian forest, forest edge, secondgrowth, and thickets Found in pine and pine-oak forests,and ranges from sea level to 1500 m elevation. One thousand from 1500-3000 m elevation.Thirty-nine specimens one hundred thirty-one specimensfrom 23 states from 10 stateswere recorded(Fig. 2). Someauthors were recorded(Fig. 2). It has not beenreported in (Ridgway 1914, Peters1940, Friedmanet al. 1950, the Baja California Peninsula. Friedman et al. Davis 1972, A.O.U. 1983) reported it for Puebla, (1950), and A.O.U. (1983) report it for Distrito but we locatedno museum specimens.Alvarez del Federal and Coahuila but no museum specimens Toro (1980) reportedthe FulvousOwl (Strix ful- exist. vescens)from the Cloud Forest of Chiapas, but we Elf Owl (MWHI) Micrathenewhitney• identifiedonly one museum specimen from the Cloud Elf Owl inhabitssaguaro deserts and arid tropical Forestas Strix variafulvescens.Six specimensin three scrub from sea level to 1800 m elevation. One hun- museums identified as Strix varia were reclassified dred sixty-sevenspecimens from 16 stateswere re- as S. v. fulvescensby J.T. Marshall (pets. comm.). corded(Fig. 2). This includesthe RevillagigedoIs- Also,two other specimensfrom Oaxacawere iden- lands in the Pacific Ocean. It has alsobeen reported tified as S.fulvescens, but they shouldbe reclassified for the state of Mexico (Peters 1940, Blake 1972), as S. v. fulvescens. and Tamaulipas (Grossmanand Hamlet 1988), but SpottedOwl (SOCC) Strix occidentalis no specimensexist. It doesnot occur in southern SpottedOwl hasa discontinuousdistribution, in- Mexico. habiting pine and pine-oak forestsfrom 1200-2500 Burrowing Owl (SCUN) Speotytocunicularia m elevation. Twenty-sevenspecimens from eight Burrowing Owl inhabitsopen lands,grasslands, stateswere recorded(Fig. 2). It has been reported prairies, and tropical scrubfrom sealevel to 1800 in Baja California (Ridgway 1914, A.O.U. 1983, m elevation.Two hundred seventy-sevenspecimens Edwards 1989, Peterson and Chalif 1989), but no from 27 stateswere recorded(Fig. 2). It has a wide specimensexist from there. A specimenfrom San distribution and occursthroughout the country in Luis Potosiand one sightrecord from Durango do suitable (Grossman and Hamlet 1988). exist (R. Clark pets. comm.),but we were not able to confirm this. Northern Saw-whet Owl (AACA) Aegoliusacadicus Northern Pygmy-Owl (GGNO) Northern Saw-whet Owl inhabits foothills with Glaucidiumgnoma pine and pine-oak forestsfrom 1800-2800 m ele- NorthernPygmy-Owl inhabits pine-oak forest and vation. Twenty-six specimensfrom 11 stateswere scrubvegetation, from 1800-3700 m elevation.One recorded(Fig. 2). It occursin northcentraland cen- hundredeighty-eight specimens from 25 stateswere tral Mexico, and hasbeen reported from Chihuahua, recorded(Fig. 2). It has also been reportedfrom Jalisco,and Veracruz (Ridgway 1914, Friedmanet Colima (Ridgway 1914, Friedmanet al. 1950), but al. 1950, Blake 1972, Davis 1972). no museum specimensare known. UnspottedSaw-whet Owl (ARID) Least Pygmy-Owl (GMIN) Aegoliusridgwayz Glaucidium minutissimum UnspottedSaw-whet Owl inhabitscloud forest, Least Pygmy-Owlinhabits tropical forest, forest pine, and pine-oak forest from 2100-3000 m ele- edge,plantations, and barrancasfrom sea level to vation.Only sevenspecimens, all from Chiapaswere 1800 m elevation.One hundred thirty-nine speci- recorded(Fig. 2). It has been reported previously mens from 14 stateswere recorded (Fig. 2). The from Chiapas(Moore 1947b,Alvarez del Toro 1980, specimendata agreewith the distributionsgiven by Davis 1972, Petersonand Chalif 1973, A.O.U. 1983, Davis (1972) and Petersonand Chalif (1989). It has Enriquez and Rangel-Salazar (pers. obs.). The SEPTEMBER 1993 MEXICAN OWL DISTRIBUTION 159

A.O.U. (1983) reported a questionablespecimen Owl (Edwards 1989, J. Marshall pers. comm.); record from Oaxaca. however,field work is still neededto verify this. The UnspottedSaw-whet Owl, StripedOwl, and Striped Owl (ACLA) Asiaclarnatar StygianOwl are listed as endangeredby the Mex- StripedOwl inhabitsdense tropical evergreen for- ican government (SEDUE 1991). The Balsas est,forest gaps, and forestedge from sealevel to 900 Screech-Owl, Bearded Screech-Owl, Crested Owl, m elevation. Twenty-six specimensfrom 3 states SpectacledOwl, Black and White Owl, Barred Owl were recorded(Fig. 2). It occursprimarily in south- and SpottedOwl are being consideredfor endan- easternMexico, but alsoin Veracruz,Chiapas (Blake geredstatus because of their low numbers,restricted 1972, Davis 1972, Peterson and Chalif 1973), and distribution, and habitat loss. Oaxaca (Binford 1989). Museum collectiondata can help delineategeo- StygianOwl (ASTY) Asiastygius graphic distribution and estimate relative abun- Stygian Owl inhabits densecloud forest in the dance.Lack of museumcollections may indicate a mountainsand rangesfrom 1500-3000 m elevation. rare, uncommon,or easily overlookedspecies. Mu- Seventeenspecimens from nine stateswere recorded seumdata can be important alsofor comparingpres- (Fig. 2). It hasalso been reported in Chiapas(Fried- ent and historical distributions. Threatened and en- man et al. 1950, Davis 1972, Alvarez del Toro 1980, dangeredspecies data in collectionsare also important A.O.U. 1983) and the Yucatan Peninsula (A.O.U. for historic location sites. On the other hand, for 1983, Edwards 1989), but, this doesnot agreewith somemuseum specimens the accompanyingdata are our dataor that of Paynter(1955) and Hartig (1979). incompleteor completelywrong. Often date of col- lection and other important information were not Long-earedOwl (AOTU) Asiaatus included. Long-earedOwl inhabitspine and pine-oakforest This is the first attempt in Mexico to draw in- and riparian forest from sea level to 1800 m eleva- formationtogether about this taxonomicgroup. We tion. Forty-one specimensfrom 13 stateswere re- hope this paper acts as a catalystto spur further corded(Fig. 2). Museum data and the literature are investigationsinto Mexican owl distribution, status, in closeagreement (Ridgway 1914, Friedman et al. biology,ecology, and conservation. 1950, Blake 1972, A.O.U. 1983). There are band recoveriesof long distancemigrants to Mexico from ACKNOWLEDGMENTS Saskatchewan,Canada (Houston 1966), Montana, We are very grateful to the museums that provided U.S.A. (D. Holt pers. obs.), and Minnesota, U.S.A. information. We thank J.T. Marshall for commentson (D. Evans pets. comm.). the manuscriptand additionalinformation. We thank R.J. Clark, C.D. Marti, H. Mikkola and an anonymousreferee Short-earedOwl (AFLA) Asiafiamrneus for commentson the manuscript. Short-earedOwl inhabitsgrasslands, open trop- LITERATURE CITED ical forests,prairies, and marshesfrom sea level to ALVAREZDEE TORO, M. 1949. Striped horned owl in 1500 m elevation.Twenty-nine specimensfrom 14 southern Mexico. Condor 51:232. stateswere recorded(Fig. 2). It has also been re- 1980. Las Aves de Chiapas. Gob. del Edo. de ported from Jalisco, Oaxaca, Puebla, Veracruz, Chiapas.Tuxtla Gutierrez, Chiapas,M6xico. Quintana Roo and Yucatan (Friedman et al. 1950, AMADON, D. AND J. BULL. 1988. Hawks and owls of Hartig 1979, A.O.U. 1983, Binford 1989, Mac- the world: a distributional and taxonomic list. Proc. Kinnon 1992). West. Found. Vertebr. Zool. 3:295-357. AMERICAN ORNITHOLOGISTS' UNION. 1983. Check-list of North AmericanBirds. 6th. Ed. Am. Ornithol. Union, DISCUSSION Washington, DC U.S.A. The taxonomyand distributionof most Mexican 1991. Thirty-eight supplementto the American Ornithologists'Union Check-list of North American owls is still incomplete.For example, subspeciesof . Auk 108:750-754. the screechowls (Otus)group discussed by Marshall BINFORD,L.C. 1989. A distributionalsurvey of the birds (1967) werereported only fromeastern Mexico. Our of the Mexican stateof Oaxaca. Ornithol.Monogr. 43. museum data, however, indicate that someof these Am. Ornithol. Union, Washington, DC U.S.A. subspeciesoccur in western Mexico. The Fulvous BLAKE,E.R. 1972. Birdsof Mexico. Univ. ChicagoPress, Owl has been considereda subspeciesof the Barred Chicago, IL U.S.A. 160 ENRiQUEZ-ROCHAET AL. VOL. 27, NO. 3

BRIGGS,M. 1954. Apparent neotenyin saw-whet owls --AND J.L. PETERS.1939. The genusOtus of Mex- of Mexico and . Proc. Biol. Soc. Wash. ico and Central America. Auk 56:38-56. 67:179-182. NORBERG,A.R. 1987. Evolution, structureand ecology BRODKORB,P. 1943. Birds from the Gulf lowlands of of northernforest owls. Pages 3-34 in R.W. Nero, R.J southern, Mexico. Misc. Publ. Mus. Zool. Univ. Mich. Clark, R.J. Knapton and R.H. Hamre lEDs.], Biology 55:88. and conservation of northern forest owls. Gen. tech BUCHANAN,M. 1964. The Mexican races of the least Rep. RM-142, Rocky Mountain Forest and Range pygmyowl. Condor66:103-112. Exp. Sta., U.S. Forest Serv., Ft. Collins, GO U.S.A. CONTRERAS-BALDERAS,A. 1992. Second record of the NORTHERN,J.R. 1965. Notes on the owls of the Tres Flammulated Owl in Nuevo Leon, Mexico. Wilson Marias Islands Nayarit, Mexico. Condor67:358. Bull. 104:375. PAYNTER,R.A. JR. 1955. The Ornithogeographyof the DAVIS,L.I. 1972. A field guideto the birds of Mexico Yucatan Peninsula.Peabody Mus. Nat. Hist. Bull. 9 and Central America. Univ. Texas Press, Austin, TX New Haven, GT U.S.A. U.S.A. PETERS,J.L. 1940. Check-list of birds of the world EDWARDS,E.P. 1989. A field guideto the birdsof Mex- Harvard Univ. Press,Cambridge, MA U.S.A. ico. Ernest P. Edwards. Sweet Briar, VA U.S.A. PETERSON,R.T. ANDE.L. CHALIF. 1973. A field guide FRIEDMAN, H., L. GRISGOM AND R.T. MOORE. 1950. to the Mexican Birds. Houghton Mifflin Go., Boston, Distributionalcheck-list of the birdsof Mexico. Cooper MA U.S.A. Ornithol. Club, Berkeley,GA U.S.A. • AND -- 1989. Aves de Mexico. Gula de GROSSMAN,M. AND.J. HAMLET. 1988. Birds of prey of Gampo. Ed. Diana, Mexico. the world. Bonanza Books, New York, NY U.S.A. RAMOS,g. 1985. Endangeredtropical birds in Mexico HARTIG, H.M. 1979. Las Aves de Yucat•tn. Fondo Edit. and Northern Central America. IGBP Tech. Publ. No Yucat•tn, M6xico. 4:305-318. HOUSTON,C. 1966. SaskatchewanLong-eared Owl re- RIDGW^Y,R. 1895. On the correctsubspecific names of coveredin Mexico. Blue Jay 24:178. the Texan and Mexican screech owls. Auk 12:389- KELSO L. AND H. KELSO. 1936. A new Ciccaba from 390. southeastern Mexico and northern Guatemala. Auk 53: 1914. The birds of North and Middle America. 215-216. Part VI. Bull. U.S. Nat. Mus. 50:1-882. MAGKINNON, B.H. 1992. Check-list of the birds of the ROWLEY,J. 1984. Breeding recordsof land birds in Yucatan Peninsulaand its protectedareas. Amigos de Oaxaca, Mexico. Proc. West. Found. l/err. Zool. 3:224. Sian Ka'an. Gancun(•uintana Roo, M6xico. RZEDOWSKI,J. 1986. Vegetaci0nde M6xico. Lirausa, MARSHALL,,J.T. ,JR. 1967. Parallel variation in North M6xico. andMiddle Americanscreech owls. Monog. West. Found. SECRETARIADE DESARROLLOURBANO Y ECOLOGiA(SE- I/err. Zool. 1:1-72. DUE). 1991. Acuerdo por el que se establecenlos --, R. BEHRSTOCKAND C. K•NIG. 1991. Voices of criterioseco16gicos GT-GERN-001-91 que determl- the Owls (Strigiformes:tytonidae, Strigi- nan las especiesraras, amenazadas,en peligro de ex- dae). Wilson Bull. 103:311-315. tinci6no sujetasa protecci6nespecial y susendemis- MOORE,R.T. 1937a. New racesof the genusOtus from mos,de la flora y acu•tticasen la RepfiblicaMexicana northwestern Mexico. Proc. Biol. Soc. Wash. 50:63-68. Diario Oficial de la FederacidnCDLII 12:7-35. 1937b. Two new owls from Sinaloa, Mexico. SmLEY,G.G. ANDJ.E. ALHQUIST. 1990. Phylogenyand Proc. Biol. Soc. Wash. 50:103-106. classificationof birds. A studyin molecularevolution. 1941. Three new racesin the genusOtus from Yale Univ. Press, New Haven, GT U.S.A. central Mexico. Proc. Biol. Soc. Wash. 54:151-160. STORER,R. 1961. Two collectionsof birds from Gam- 1947a. New owlsof the generaOtus and Glau- peche,Mexico. Univ. Mich. Mus. Occ. Papers Zool cidium. Proc. Biol. Soc. Wash. 60:141-146. No. 621:1-20. 1947b. Two new owls, a swift and poorwill from Mexico. Proc. Biol. Soc. Wash. 60:141-146. -- ANDJ.T. MARSHALL,JR. 1959. A new race of from Oaxaca. Condor 61:224-225. Received13 November 1992; accepted15 June 1993