Cotinga 16 Birds of San Juan M ixtepec, district of Miahuatlán, Oaxaca, Mexico Eugene S. Hunn, Donato Acuca Vásquez and Patricia Escalante Cotinga 16 (2001): 14–26 Se reporta la situación de 188 especies de aves observadas (o reportadas por gente del lugar en cinco casos) en los municipios de San Juan y San Pedro Mixtepec, distrito de Miahuatlán, Oaxaca, México, de julio de 1996 a marzo del 2000, en 235 días de trabajo de campo durante 57 visitas. Las observaciones fueron hechas por los autores bajo una investigación etnobiológica conducida por ESH. El área comprende cerca de 57 km2 del lado norte de la Sierra de Miahuatlán, entre los 1.630 y 3705 msnm. Sus hábitats, en orden de altitud, son: bosque subtropical caducifolio y matorral subtropical, bosque de galería, matorral de encino o chaparral, cultivos y pastizales, encinares, bosque de pino-encino seco, bosque de pino-abeto húmedo y bosques de Pinus ruáis de altura. De nuestros reportes lo más notable es el registro de la sita enana Sitta pygmaea que aparentemente es un residente permanente del área, y cuatro primeros registros para la Sierra Madre del Sur de Oaxaca, los tres primeros son los registros más meridionales para las especies en cuestión, para el tecolote enano Micrathene whitneyi, el reyezuelo de oro Regulus satrapa, el picogrueso norteño Coccothraustes vespertinus y el picogrueso encapuchado C. abeillei. Introduction as it contains an extensive ‘island’ of pine forest We summarise the status of 188 species of birds above 3400 m, isolated by at least 300 km from simi­ observed (or reported by local residents in five cases) lar high terrain both in both Mexico’s Central in or near the municipio of San Juan Mixtepec (in­ Volcanic Axis and on the Chiapas-Guatemala bor­ cluding portions of adjacent San Pedro Mixtepec), der. district of M iahuatlán, Oaxaca, Mexico (Fig. 1) in Highlights include a species new to the Oaxaca July 1996-March 2000. Observations were made by state list — Pygmy Nuthatch Sitta pygmaea, which the authors during the course of an ethnobiological is apparently a permanent resident in the study research project in this community directed by area — and four first reports from the Sierra Sur of ESH6. The municipio7 encompasses c. 57 km2, on the Oaxaca, the first three representing southernmost north side of the Sierra de Miahuatlán, at 1630– records for the species: Elf Owl Micrathene whitneyi, 3705 m. Major habitats include — in order of Golden-crowned Kinglet Regulus satrapa, Evening increasing elevation —deciduous subtropical forest Grosbeak Coccothraustes vespertinus and Hooded and subtropical scrub, riparian woodland, oak scrub Grosbeak C. abeillei. Our observations of Buff­ or chaparral, cultivated and fallow fields and pas­ breasted Flycatcher Empidonax fulvifrons are the tures, oak woodland, arid pine–oak forest, humid second and third reports from the region. Records pine–fir forest and high-elevation Pinus rudis for­ of Green-fronted Hummingbirds A m a zilia est2. The human population — estimated at 850 in viridifrons, at 2000–2050 m near town, are the 1996 (Hermilo Silva Cruz pers. comm.) — is based highest published reports for the species. South in a settlement at c. 2070 m (16°16’N 96°18’W), re­ Mexican highland endemics at the south-east lim­ ferred to as the ‘town’ within the species accounts. its of their range include: Dusky Hummingbird The vast majority of human residents are subsist­ Cynanthus sordidus, Pileated Flycatcher Xenotriccus ence farmers, owning variable numbers of livestock, mexicanus, Slaty Vireo Vireo brevipennis, Boucard’s predominantly goats, with some sheep, donkeys, and Wren Campylorhynchus jocosus, Ocellated Thrasher cattle. The settlement is 47 km south-east, by an Toxostoma ocellatum, White-throated Towhee Pipilo all-weather dirt road, of the district capital and albicollis and Bridled Sparrow A im ophila market centre of Miahuatlán, on the paved high­ mystacalis. Cooper’s Hawk Accipiter cooperii and way (federal route 175) between Oaxaca City and Violet-green Swallow Tachycineta thalassina were the Pacific Coast. The southern part of the municipio observed year-round, though definite nesting was includes an extensive region above 3000 m along not documented; neither is known to breed south of the crest of the drainage divide between the short north and central Mexico. Pacific Coastal streams and the Tehuantepec River basin. This high-elevation area is accessible by a M e t h o d s second dirt road that runs east from the paved high­ Observations were made during 57 visits to San way at San José del Pacifico, via San Mateo Rio Juan Mixtepec, on a total of 235 days, and were op­ Hondo, and La Cieneguilla. This region is little portunistic, as primary research goals were to collect known ornithologically, but is of particular interest plants and record local Zapotec names and local 14 C otin ga 16 Birds of San Juan Mixtepec, district of Miahuatlán, Oaxaca, Mexico cultural knowledge concerning plants and animals. ture and grazing activities. Communal forests above However, we were able to visit all major habitat 2200 m, in contrast, are well preserved and have types and all major regions of the community re­ been subject to very limited commercial logging to peatedly during all months. Research was approved date. Forest fires are frequent, but crown fires are by the local community assembly, and capture of typically restricted to high ridges. We observed sev­ animals, and collection of plants and insects, were eral pines (e.g. Pinus douglasiana, P. ayacahuite) conducted under permit, to ESH, from the Mexican and oaks (Quercus laurina), at 2400–2900 m, with government. ESH tape-recorded vocalisations, es­ diameters >1 m that probably are several hundred pecially in spring when breeding species were years old. The woody dominants in each major habi­ especially vocal. DAV mist-netted a total of 153 birds tat (following Binford2) are as follows. on 16 days, which were measured and photographed prior to release. Birds found dead or casualties of Highland pine forest mist-netting were prepared as specimens by DAV Above 3200 m, forests are near-uniform stands of and have been deposited in the collection of the Pinus rudis with Alnus jorullensis var. jorullensis Instituto de Biología of the Universidad Nacional in clearings and along streams. Characteristic spe­ Autónoma de México, Mexico D.F. cies of the shrub layer are Senecio sp., Lobelia sp., Arbutus xalapensis, L upinus spp., Ceanothus Local habitats coeruleus and Penstemon spp., often with a low Lands near and below the town have been occupied ground cover of Pernettya sp. Agave atrovirens is for at least 1500 years, probably by directly ances­ common on open ridges and in areas made open by tral Zapotec-speaking populations9. Habitats below crown fires. 2,200 m have been extensively modified by agricul­ Figure 1. Map of Oaxaca, Mexico showing location of the study site in the municipios of San Juan and San Pedro Mixtepec, district of Miahuatlán, on the north slope of the Sierra de Miahuatlán. 15 Cotinga 16 Birds of San Juan Mixtepec, district of Miahuatlán, Oaxaca, Mexico Humid pine–oak and pine–fir forest rescent or columnar cacti Opuntia pilifera , At 2700–3400 m, particularly in moist canyons, one Stenocereus treleasii and S. pruinosus, a few finds Abies guatemalensis mixed with Pinus rudis, Cephalocereus chrysacanthus, Mitrocereus fulviceps P. ayacahuite, P. pseudostrobus, Quercus laurina, and Myrtillocactus schenkii occur at the lower bor­ Alnus jorullensis, Arbutus xalapensis and ders of San Juan Mixtepec communal lands. Cheiranthodendron pentadactylon. E piphytic bromeliads (Tillandsia spp.) are common on oaks. Riparian groves Common shrubs include Baccharis heterophylla, These groves are prominent below 2300 m where Senecio spp., Stevia spp., Lobelia sp., Sambucus the closed pine–oak forests give way to more open mexicanus, Satureja macrostema and Rubus spp. terrain. Characteristic trees of this zone are Alnus acuminata and Salix bonplandiana. Salix chilensis, Arid pine–oak forest Populus mexicanum and Fraxinus uhdei are scarce; Forests of this type, below c.2200 m, are rather open Taxodium mucronatum and Ligustrum lucidum and predominantly oak (and can be described as occur below 1700 m. Common shrubs are Baccharis oak woodland); the pine canopy is enclosed above salicifolius and Cornus excelsa. This zone is fre­ 2300 m. Dominant pine species include Pinus quently planted with fruit trees, including douglasiana, P. oaxacana and P. teocote; P. leiophylla Mangifera indica , Annona cherimola, Persea occurs locally, while P. ayacahuite is conspicuous am ericana, Byrsonima crassifolia , P sidium above 2500 m. Common oaks include Quercus guajuava, Crataegus pubescens, Malus pumila , acutifolia and Q. crassifolia, with Q. castanea, Q. Prunus persica, P. serotina ssp. capuli, Casimiroa magnoliifolia, Q. obtusata and Q. conzattii at lower edulis and Citrus spp. elevations. Quercus laurina is common above 2400 m. Alnus jorullensis var. lutea and A. arguta are com­ Modified terrestrial habitats mon understorey trees above 2400 m. Arbutus Gardens, orchards, hedgerows, and road and trail xalapensis is common in the understorey through­ margins in and near town (at 1900–2200 m) are out. Clearings in pine forests, above 2300 m, are characterised by anthropogenic woody vegetation. typically associated with seepage areas and are Exotic trees planted in town include Casuarina ringed by up to 3-m-tall Baccharis heterophylla. equisetifolia , Jacaranda mimosifolia , M elia azedarach, Ficus nitida and Eucalyptus globulus. Oak scrub or chaparral Cultivated fruit trees include Ficus carica, Persea Drier slopes, at 2000–2300 m, may lack trees, but americana, Morus celtidifolia, Punica granatum , are covered by dense stands of 2–3-m-high shrubs, Cydonia oblonga, Eriobotrya japonica, M alus predominantly Arctostaphylos pungens and pum ila, Prunus persica,P. armeniaca, Citrus limetta Comarostaphylis glaucescens, Cercocarpus and C. limonia. Living fences are of Agave spp., macrophylla, Calliandra spp., Dodonea viscosa and Bursera spp., Opuntia spp., Stenocereus spp., Lantana spp.