Essay Benefits of Studies of Overwintering Birds for Understanding Resident Bird Ecology and Promoting Development of Conservation Capacity STEVEN C. LATTA ∗ AND JOHN FAABORG† ∗ Department of Conservation and Field Research, The National Aviary, Pittsburgh, PA 15212, U.S.A., email steven.latta@aviary.org †Department of Biological Sciences, University of Missouri, Columbia, MO 65211, U.S.A. Abstract: Funding of ecological research and monitoring of Neotropical migratory birds on their overwinter- ing grounds has benefited both migratory and permanent-resident species. Using examples from our work in Puerto Rico and the Dominican Republic, we demonstrate that ecological research of overwintering migrants often provides information about the ecology and demography of little-known tropical resident birds. Critically important long-term monitoring in Puerto Rico with a focus on winter residents has provided information on the relationships between annual rainfall and fluctuations in resident bird populations and survival rates. It also has alerted local biologists to declines in resident bird populations, including a decline apparently driven by the entry of a brood parasite. But migrant-focused research may also have had an underappreciated effect on the development of conservation capacity and conservation efforts in host countries. Investments in research on Neotropical migrants overwintering on Hispaniola have resulted in a huge increase in field training of students and wildlife professionals, promoted conservation awareness at local and national lev- els, played an important role in the growth and professionalization of key environmental organizations, spawned a growing ecotourism industry for bird-watching, and driven national park management planning and conservation efforts for all bird species. We encourage funding organizations and agencies to consider the broader impacts of funding migratory-bird research and monitoring efforts, and we encourage researchers in the tropics to use protocols that provide the most information about all the birds that use the study areas involved and to be aware of important opportunities that they may have to build capacity in host countries. Keywords: capacity building, ecotourism, funding priorities, monitoring, Neotropical migratory birds Beneficios de los Estudios de Aves Invernantes para Entender la Ecolog´ ıa de Aves Residentes y Promover el Desarrollo del Potencial para Conservar Resumen: El financiamiento de investigaci´ on ecol´ ogica y el monitoreo de aves migratorias neotropicales en sus zonas de invernaci´ on ha beneficiado tanto a especies migratorias como residentes. Utilizando ejemplos de nuestro trabajo en Puerto Rico y Rep´ ublica Dominicana, demostramos que la investigaci´ on ecol´ ogica de migratorias neotropicales a menudo proporciona informaci´ on sobre la ecolog´ ıa y demograf´ ıa de aves residentes tropicales poco conocidas. El monitoreo a largo plazo en Puerto Rico con enfoque en las residentes de invierno ha proporcionado informaci´ on sobre las relaciones entre la precipitaci´ on anual y fluctuaciones en las poblaciones y tasas de supervivencia de aves residentes. Tambi´en ha alertado a bi´ ologos locales sobre declinaciones en las poblaciones de aves residentes, incluyendo una declinaci´ on provocada aparentemente por la entrada de un par´ asito de cr´ ıa. Pero la investigaci´ on centrada en migratorias tuvo un efecto subestimado sobre el desarrollo del potencial para conservar y los esfuerzos de conservaci´ on de los pa´ ıses hu´ esped. Las inversiones en investigaci´ on de migratorias neotropicales invernantes en Hispaniola han resultado en un enorme incremento del entrenamiento en campo de estudiantes y profesionales en vida silvestre, promovido Paper submitted April 25, 2008; revised manuscript accepted July 29, 2008. 286 Conservation Biology, Volume 23, No. 2, 286–293 C 2008 Society for Conservation Biology DOI: 10.1111/j.1523-1739.2008.01098.x