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ORNITOLOGIA NEOTROPICAL 15: 447–482, 2004 © The Neotropical Ornithological Society AVIAN DIVERSITY IN THE MOSKITIA REGION OF HONDURAS David L. Anderson1,4, David A. Wiedenfeld2, Marc J. Bechard1, & Stephen J. Novak3 1Raptor Research Center, Department of Biology, Boise State University, Boise, ID 83725, USA. 2Charles Darwin Research Station, Puerto Ayora, Galapagos, Ecuador. 3Department of Biology, Boise State University, Boise, ID 83725, USA. Resumen. – Avifauna de la región de la Moskitia en Honduras. – La Moskitia al noreste de Honduras es considerada una región de alta diversidad en especies de aves, supuestamente por su inmensidad de hábitat natural y la poca intervención humana. Reportamos 358 especies de aves en la Moskitia de acuerdo a estudios hechos recientemente y datos históricos, el doble de la cantidad de especies ya reportadas. Sesenta y cinco especies habitan exclusivamente en bosques latifoliados lluviosos donde sus poblaciones son afectadas por la deforestación en Centro América. Cinco especies están en peligro de extinción a nivel mundial y otra está restringida (endémica) a la región. Incluimos una lista de todas las especies reportadas por categoría de residencia, estado de peligro, frecuencia de observación, y forma de documentación. Ade- más, incluimos una segunda lista de 145 especies que no han sido reportadas en la Moskitia pero que tie- nen altas posibilidades de encontrarse en la región. En conclusión, la Moskitia hondureña es notablemente importante para la conservación de la biodiversidad a nivel nacional y regional. Mientras tanto, es necesario realizar trabajos del campo adicionales para mejor entender el estado, la distribución, y la abundancia de aves en el noreste del país. Abstract. – The Moskitia region of northeastern Honduras has long been suspected of supporting high avian diversity, due to the diversity and large expanse of habitats, some with little or no known history of large-scale human disturbance. We have drawn on recent field studies combined with historic data to report on 358 species for this region, more than twice the number of species previously reported. This number represents half the total number of bird species found in Honduras. A total of 65 species are restricted to mature lowland broadleaf forest and susceptible to habitat loss throughout Central America. Five species are recognized as deserving conservation concern and one is regionally range-restricted (endemic). We include a complete list of reported species giving the residency status, threatened status, fre- quency of observation, and method of substantiation. A second list includes 145 species that likely occur in the Honduran Moskitia but have not yet been reported. We conclude that the Honduran Moskitia is especially important for conserving regional biodiversity. Meanwhile, much additional fieldwork is needed to understand the status and abundance of birds in northeastern Honduras. Accepted 31 July 2004. Key words: Birds, avifauna, diversity, Moskitia, Honduras. INTRODUCTION second largest country in Central America. Within its boundaries is a diverse mosaic of With an area of 112,090 km2, Honduras is the habitats that range in elevation from 0 to ___________ 2880 m and include mountainous highlands 4Current address: Museum of Natural Science, 119 interspersed with arid valleys, 120 km of Foster Hall, Louisiana State University, Baton Pacific and 650 km of Caribbean coastlines Rouge, LA 70803, USA. E-mail: birds@ with associated coastal plains, mangrove birdinghonduras.com swamps and estuaries, freshwater lagoons, 447 ANDERSON ET AL. s and forest coverage. as, with protected area protected with as, FIG. 1. Gracias a Dios departmentFIG. in Hondur 448 AVIFAUNA OF THE HONDURAN MOSKITIA humid and dry tropical forests, cloud forests, and cultural characteristics. The lowland broa- pine and oak forests, and offshore islands and dleaf forests of northeastern Honduras and cays. Owing partly to its habitat diversity, northern Nicaragua measure more than Honduras supports a high diversity of some 33,900 km2, with approximately half of the 701 recorded bird species (Bonta & Anderson forest found in each country. (D. Parent 2002). Of this total, 16 species are regional unpubl.). Pine savanna totals another 17,500 endemics confined to northern Central Amer- km2. These combined forests constitute one ica, one species is found only in Honduras, of the largest remaining forest blocks in Cen- and various species are in danger of extinction tral America. The ecosystems of the Moskitia at the national, regional, and global levels, more closely approximate their pre-industrial such as the Honduran Emerald (Amazilia state than any similar-sized areas in the Cen- luciae), Harpy Eagle (Harpia harpyja), and tral American isthmus. For this reason, 34,655 Golden-cheeked Warbler (Dendroica chryso- km2 of land have been set aside in four paria), among others (BirdLife International national and international protected areas (O. 2000, Bonta & Anderson 2002). Munguía pers. com). In Honduras, the low- The lowland rain forests of northeastern land broadleaf forests in the northeastern part Honduras have long been believed to support of the country lie in four departments: Colón, high bird species diversity, owing to their large El Paraíso, Olancho, and Gracias a Dios. The size and pristine condition. Although museum latter possesses the greatest extent of forest collectors visited Honduras in the 19th and and the lowest human population densities in 20th centuries, and the country’s avifauna was Honduras, and comprises the large majority addressed in an early ornithological mono- of the area called the Moskitia in Honduras. graph (Monroe 1968), there have been We will therefore use the departmental limits extremely few ornithological studies under- of Gracias a Dios (hereafter “the Honduran taken in eastern Honduras (Marcus 1983, Moskitia”) to delimit the geographic area Marcus 1984, Frederick et al. 1997, Anderson from which our data are derived. 1998, Anderson et al. 1998, Anderson 2000). Gracias a Dios measures 16,630 km2, To date, an accurate assessment of the Moski- ranges in elevation from 0 to 1356 m, and has tia avifauna has remained elusive. a human population density of approximately Our objectives in this paper are to 2.2 persons/km2 (Turner 2004). Lowland describe the avian diversity of the Honduran broadleaf rain forests in this department alone Moskitia, point out species of conservation total 6500 km2, with pine savanna encompass- concern, and estimate the number of bird spe- ing approximately the same area (Fig. 1). The cies present but as yet undetected in the study physiography of the Moskitia is characterized area. by north-south transverse mountain ranges descending onto the broad littoral plain of the STUDY AREA AND METHODS Río Patuca and Río Segovia. Pronounced dry (January–May) and wet (June–December) sea- Study area. The region known as the Moskitia sons occur, with an annual precipitation of includes land in both eastern Honduras and 2700 mm recorded on the Caribbean coast at northern Nicaragua. Because the Moskitia Belén (Dodds 1994). Primary lowland rain straddles the boundary of Honduras and Nic- forests are comprised of broadleaf evergreen aragua, it is difficult to accurately determine trees (e.g., Swietenia macrophylla, Pterocarpus offici- the size and geographic boundary of the nalis) with occasional deciduous species (Tabe- region, which is loosely defined by biological buia chrysantha, Ceiba pendantra; Hardy & 449 ANDERSON ET AL. Sutherland 1986). The dense canopy is typi- marshy or swampy areas); coastal habitats and cally 25–35 m high, and epiphytes are abun- mangroves; open habitats, usually highly dant. altered by human activity, including agricul- ture; aerial, for swifts only; all, for species Field observations. Our observations of birds in found in all habitats. As with all studies of the Moskitia are derived from three principal tropical birds, assigning species to a habitat time periods. DLA lived in the Río Plátano category can be problematic and the result of Biosphere Reserve in the village of Las Marías generalizations. Our intent was to provide a from January to June 1996 and 1997, and in framework for understanding the distribu- the Tawahka Asagni Biosphere Reserve in the tion of birds within habitats in the Honduran village of Krausirpe from January to May Moskitia and point future researchers toward 1999. DAW worked in gallery forest and pine meaningful studies of bird species distribu- savanna in the area of the Río Plátano east- tion in the Moskitia. ward to the Nicaraguan border from February to March and from August to October of Residency status classification. We classified bird 1992. species into five categories of residency sta- tus: permanent resident, Nearctic migrant, Frequency status. We assigned a frequency of partial migrant, intratropical migrant, and observation status to species based on our transient. All resident, nonmigratory species observations. The frequency classifications were classified as “permanent residents” and we used were: common, at least one individ- included species for which breeding was ual detected every day in the field; fairly com- either known or presumed. “Nearctic mon, at least one individual detected every migrants” were species that spent an week in the field; uncommon, at least one extended period (generally many months) of individual detected during a season (three the year in the Honduran Moskitia before months); rare, for species we