The Response of Avian Feeding Guilds to Tropical Forest Disturbance MICHAEL A. GRAY, ∗ SANDRA L. BALDAUF, PETER J. MAYHEW, AND JANE K. HILL Department of Biology (Area 18), University of York, York YO10 5YW, United Kingdom Abstract: Anthropogenic habitat disturbance is a major threat to tropical forests and understanding the eco- logical consequences of this disturbance is crucial for the conservation of biodiversity. There have been many attempts to determine the ecological traits associated with bird species’ vulnerability to disturbance, but no attempt has been made to synthesize these studies to show consensus. We analyzed data from 57 published studies (covering 1214 bird species) that investigated the response of tropical bird assemblages to moderate forest disturbance (e.g., selective logging). Our results show that the mean abundance of species from six com- monly reported feeding guilds responded differently to disturbance and that species’ ecological traits (body size, local population size, and geographic range size) and evolutionary relationships may influence responses in some guilds. Granivore abundance increased significantly and insectivore and frugivore abundance de- creased significantly following disturbance. These general conclusions were robust to the effects of ecological traits and phylogeny. Responses of carnivores, nectarivores, and omnivores were less clear, but analyses that accounted for phylogeny indicated that these guilds declined following disturbance. In contrast to the other guilds, the reported responses of carnivores and nectarivores differed among regions (Asia vs. Neotropics) and were influenced by the sampling protocols used in different studies (e.g., time since disturbance), which may explain the difficulty in detecting general responses to disturbance in these guilds. Overall, general patterns governed the responses of species to habitat disturbance, and the differential responses of guilds suggested that disturbance affects trophic organization and thus ecosystem functioning. Keywords: habitat modification, meta-analysis, phylogeny, tropical diversity Respuesta de Gremios Alimentarios de Aves a la Perturbaci´ on de Bosques Tropicales Resumen: La perturbaci´ on antropog´ enica del h´ abitat es una de las principales amenazas a los bosques tropicales y el entendimiento de las consecuencias de esta perturbaci´ on es crucial para la conservaci´ on de la biodiversidad. Ha habido muchos intentos para determinar las caracter´ ısticas ecol´ ogicas asociadas con la vulnerabilidad de especies de aves a la perturbaci´ on, pero no ha habido intentos para sintetizar estos estudios para mostrar consenso. Analizamos datos de 57 estudios publicados (abarcando 1214 especies de aves) que investigaron la respuesta de ensambles de aves tropicales a la perturbaci´ on moderada de bosques (e.g., tala selectiva). Nuestros resultados muestran que la abundancia promedio de especies de seis gremios alimentarios com´ unmente reportados respondi´ o distintamente a la perturbaci´ on y que las caracter´ ısticas ecol´ ogicas (tama˜ no corporal, tama˜ no de la poblaci´ on local y extensi´ on del rango geogr´ afico) y las relaciones evolutivas de las especies pueden influir en las respuestas de algunos gremios. La abundancia de gran´ ıvoros increment´ o significativamente y la abundancia de insect´ ıvoros y frug´ ıvoros disminuy´ o significativamente despu´ es de la perturbaci´ on. Estas conclusiones generales fueron robustas para los efectos de las caracter´ ısticas ecol´ ogicas y filogenia. Las respuestas de carn´ ıvoros, necatar´ ıvoros y omn´ ıvoros fueron menos claras, pero los an´ alisis que consideraron la filogenia indicaron que estos gremios declinaron despu´ es de la perturbaci´ on. En contraste con otros gremios, las respuestas reportadas para carn´ ıvoros y nectar´ ıvoros fueron difirieron entre regiones (Asia vs. Neotr´ opico) y fueron influenciadas por los protocolos de muestreo utilizados en diferentes ∗ email mg162@york.ac.uk Paper submitted December 19, 2005; revised manuscript accepted April 18, 2006. 133 Conservation Biology Volume 21, No. 1, 133–141 C 2007 Society for Conservation Biology DOI: 10.1111/j.1523-1739.2006.00557.x