Meeting Abstract

P2.40  Tuesday, Jan. 5  Does seasonality determine the utility of landscape corridors for promoting seed dispersal by birds? EVANS, D.M.; Univ. of Washington, Seattle dmevans@uw.edu

Habitat fragmentation is a leading cause of species decline and extinction. Habitat corridors are a common strategy for mitigating fragmentation and creating connectivity. Plant fitness can hinge upon birds dispersing seeds, yet we know little about the mechanisms by which fragmentation and connectivity impact bird dispersal behavior. Seasonality governs movement and population structure of seed eating birds in many habitats. This study assesses seasonal variation in patterns of seed dispersal in an experimentally fragmented forest in order to compare the utility of corridors for promoting dispersal by birds in summer and winter. This study is ongoing at the Savannah River Site in South Carolina. The site consists of eight experimental landscapes; each has five 1.3-hectare habitat patches arranged with four peripheral patches equidistant from a central patch. One peripheral patch in each landscape is connected to the central patch by a corridor. Habitat within the patches is young longleaf pine (Pinus palustris) savannah; the matrix separating the patches is mature loblolly pine (Pinus taeda) forest. I use a single species of fruiting plant, Solanum americanum, for this study. S. americanum does not occur naturally in the patches. During summer 2009 I planted 38 fruiting plants in the center patch of each landscape, and I installed 16 seed traps on perch poles in every patch. Birds dispersed seeds into 3 of 8 center patches and 5 of 24 isolated peripheral patches. No seeds were dispersed down corridors. Most birds eating S. americanum fruits in summer are territorial; thus their foraging and movement may be driven more by breeding requirements than by landscape features like corridors. I will repeat this study in winter 2010, when seed eating birds at SRS are not territorial.