PS 65-115
Agricultural development changes native bee community composition in Central Texas peach orchards

Thursday, August 8, 2013
Exhibit Hall B, Minneapolis Convention Center
Sarah Cusser, Evolution, Ecology and Behavior, University of Texas, Austin, TX
Shalene Jha, Integrative Biology, University of Texas at Austin, Austin, TX

Forty percent of the Earth’s habitable surface is covered by agriculture. Agricultural landscapes rely heavily on ecosystem services, including pollination provided by bees to produce marketable food, fiber, and forage plants. However, agricultural development alters bee population dynamics, in part by changing the distribution and composition of necessary floral and nesting resources. We hypothesized that agricultural landscapes act as barriers or filters to foraging and dispersing bees, eliminating those subsets of the bee community not adapted to the shifting conditions of modified agricultural landscapes. Under this scenario, species that remain in landscapes after agricultural modification are likely to be those with ecological traits that predispose them to negotiating novel landscapes. In this study we used trap nests and active netting to investigate the influence of agricultural development and land-use change on native bee community composition in Texas peach orchards ranging in the degree of agricultural modification and surrounding habitat composition. 


We found that agricultural development altered bee community composition in terms of both species richness and abundance. Specifically, we found that agricultural bee communities were composed of a subset of the regional bee community. Overall these findings indicate that aspects of agricultural development and land use change can systematically alter bee community composition, affecting species richness and abundance.  Future work will focus on quantifying changes in pollen deposition and fruit set associated with changes in bee community composition.