PARENT SESSION
Contributed Oral Session 109: Agroecology: Soils; Nutrient Cycling
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 513 A, Level 5, Palais des congrès de Montréal
Bird insectivory reduces insect damage to Theobroma cacao crops in Bocas del Toro, Panama.
Van Bael, Sunshine*,1, 2, Bichier, Peter1, Greenberg, Russell1, 1 Smithsonian Migratory Bird Center, Washington, DC, USA2 Smithsonian Tropical Research Institute, Balboa, ANCON, Republic of Panama
ABSTRACT- The degree to which agriculture can be compatible with conservation goals (e.g., preserving natural biodiversity) depends on land-use practices. In turn, natural biodiversity may confer a variety of services to farmers including biocontrol of insects and pathogens. Theobroma cacao , the cocoa tree, is grown under the shade of pre-existing rainforest trees or planted canopy trees. Relative to alternative land-uses, cocoa farms maintain habitat for a wide diversity of rainforest plants and animals, including migratory birds. We estimated the abundance and species richness of birds in cocoa farms and forest fragments of Bocas del Toro province, Panama. We observed a total of 243 bird species with 126 bird species in forest remnants and 178 bird species in cocoa farms. Cocoa farms provided habitat for 35 bird species that were seasonal migrants and 23 resident bird species were seen with nesting material. Concurrent with the bird censuses, we used an exclosure experiment to determine whether birds affect insect densities and insect damage on cocoa trees. Over the course of one year, bird insectivory significantly decreased local arthropod abundances and damage to leaves of cocoa trees. Bird limitation of arthropods was especially intense during periods when migratory birds were present. Our results corroborate earlier findings from coffee plantations that shaded crops can provide important habitat for migratory birds and that crops benefit from bird insectivory.
Key words: agroecology, migratory birds, insectivory, herbivory