International Research Fellowship Program: Tropical Forest Songbird Behavior and Movements in Human-Dominated Landscapes

Withey John C, Seattle WA

Investigators

Abstract

0602091 Withey The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twelve-month research fellowship by Dr. John C. Withey to work with Dr. William F. Laurance at the Smithsonian Tropical Research Institute (STRI) in Panama City, Panama. Support for this project comes from the Office of International Science and Engineering's (OISE) Americas Program. Human destruction, alteration, and fragmentation of forest habitats have caused declines in native bird populations and loss of avian biodiversity through local extinctions. Conversion of forests continues at a rapid pace, especially in the tropics. The response of songbirds to forest loss and fragmentation in the neotropics varies, and the mechanisms producing declines in populations and biodiversity in the tropics are different from those found in temperate regions. In studies of fragmented landscapes scientists have increasingly recognized the importance of the matrix: the modified habitats surrounding forested areas. Whether and how tropical forest songbirds use lands in the matrix is not well known. This type of information is critical for understanding how birds respond to habitat modification and fragmentation, and how to manage human-dominated landscapes in the tropics to help conserve native forest species. The proposed research questions include: 1) in a fragmented landscape, how do tropical forest songbirds use matrix habitats (for breeding, foraging, as movement corridors, not at all); 2) how does avian use of matrix habitats vary by the type of land cover or land use; and 3) does the dispersal limitation hypothesis explain the absence of certain species from forest fragments (i.e., does movement into and use of matrix habitat predict occurrence in small forest fragments)? Fragmented forests in the Panama Canal area (Pacific slope lowlands) will be used as study sites and three focal bird species will be captured and tracked using radiotelemetry. Most previous research of bird occurrence in the matrix has focused on the community level and detailed movements and behavior of tropical birds in the matrix are only just being studied. This research will benefit greatly from years of studies of Panama's avifauna, particularly in the Canal area, and the experience of Dr. Laurance and his colleagues at STRI. Dr. Laurance has studied the effects of habitat fragmentation on tropical forest ecosystems over many years, and has specifically pointed out the importance of the matrix to the functioning of remaining forest patches.