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Postdispersal fate of seeds from Ocotea endresiana (Lauraceae), a bird-dispersed Neotropical montane tree, was studied in Costa Rica to determine the influence of seed dispersers, seed predators, and microhabitat characteristics on seedling recruitment. Particular emphasis was placed on finding naturally dispersed seeds in order to study the link between dispersal and postdispersal fate of seeds. Four species of birds (Emerald Toucanet, Aulacorhynchus prasinus; Resplendent Quetzal, Pharomachrus mocinno; Three-wattled Bellbird, Procnias tricarunculata; and Mountain Robin, Turdus plebejus) dispersed the seeds by regurgitation, and one species (Black Guan, Chamaepetes unicolor), by defecation. Most seeds (80%) were dispersed within 25 m of parent trees and under high (>92%) canopy cover. Bellbirds deposited 52% of the seeds they dispersed under habitual song perches in standing dead trees on the edges of treefall gaps >25 m from parent trees. In contrast, the other four species dispersed only 6% of the seeds...

As habitat loss continues, natural protected areas will become islands in human-modified landscapes; maintenance of functional communities and ecosystems will depend on properly designed protected areas. We demonstrate that incorporating regional habitat linkages that allow for seasonal migrations of intratropical resident species must be a major design criterion for establishing protected areas. Using radiotelemetry, we monitored the seasonal movements of one such migrant, the Resplendent Quetzal (Pharomachrus mocinno), a large, frugivorous bird, one of many tropical residents known to migrate altitudinally within Mesoamerica. Based on three years of data we determined that quetzals followed a complicated local migration that linked four montane life zones. Using this species as an indicator revealed that the configuration of the Monteverde reserve complex in the Tilaran Mountains in west-central Costa Rica lacked sufficient habitat distribution to conserve montane biodiversity. On the basis of these results, we propose that the three-step process proposed by Soule and Simberloff (1986) for estimating minimum sizes of reserves be amended to include a fourth step: The critical habitats used throughout the annual cycles of target or keystone species must be identified and adequately protected. Natural protected areas can be considered adequately designed only when sufficient area with a full complement of ecologically linked habitats is included. A medida que la perdida de habitat continua, las areas naturales protegidas se iran transformando en islas dentro de paisajes modificados por las actividades humanas; el mantenimiento de comunidades y ecosistemas funcionales dependera de areas protegidas correctamente disenadas. En el presente estudio demostramos que la incorporacion las conecciones entre habitats de una misma region que permitan las migraciones estacionales de especies residentes intratropicales debe ser un criterio de diseno de gran importancia para el establecimiento de areas protegidas. Por medio del uso de radiotelemetria, supervisamos los movimientos estacionales de uno de tales migrantes, el Quetzal Resplandeciente (Pharomarchrus mocinno), un ave frugivora grande y uno de los tantos residentes tropicales que migran en forma altitudinal dentro de Mesoamerica. En base a tres ano de datos determinamos que los quetzales siguieron una migracion local complicada que conecto cuatro biomas montanos. El uso de esta especie como indicador, revelo que la configuracion del complejo de reservas de Monterverde en las Montanas Tilaran, en el centro-oeste de Costa Rica carecia de una distribucion de habitat suficiente para conservar la biodiversidad montana. Sobre la base estos resultados, proponemos que el proceso en tres etapas para estimar los tamanos minimos de las reservas propuesto por Soule y Simberloff (1986) sea modificado de tal forma que incluya una cuarta etapa; los habitats criticos usados a lo largo de los ciclos anuales de las especies clave deben ser identificados y protegidos adecuadamente. Las areas naturales protegidas solo pueden ser consideradas como disenadas adecuadamente cuando se incluya un area suficiente que comprenda un complemento de los habitats conectados ecologicamente.

Researchers at the Miguel Alvarez del Toro Regional Zoo (ZooMAT), in Chiapas, Mexico, have successfully bred a resplendent quetzal (Pharomachrus mocinno) chick in captivity for the first time. Quet? zals were sacred in Mayan culture; they symbolized freedom, precisely because they would die when caged. Included in Appendix 1 of the CITES convention, the fruiteating quetzal, with its impressive red, blue, and green plumage, is endangered by habitat degradation, hunting, and trafficking. "This achievement is the result of many years of research", explains Carlos Guichard, ZooMAT director (Tuxtla, Chiapas). "In the 1980s, studies were carried out in the Chiapas mountains to understand the biology and behavior of the quetzal in the wild", he continues. "Following this work, the bird's habitat was protected by the estab? lishment of the 100000-ha Triunfo A newly hatched quetzal chick.