US-IALE 2018

AUTHORS: Beatriz Otero-Jimenez*, Department of Ecology and Evolutionary Biology, University of Michigan; Kevin Li, Department of Crop Science, University of Gottingen

ABSTRACT: Agricultural production has expanded rapidly in tropical regions, transforming the landscape and fragmenting tropical forests. However, little is known about the long­term effects of agricultural production practices (i.e., management intensification) on population connectivity and dispersal. Our study integrates genetic and landscape data to examine landscape factors influencing the connectivity of tropical small mammals. Specifically, we investigated landscape factors driving the population structure of Heteromys desmarestianus goldmani, a common forest rodent, in a coffee agroecosystem. We evaluated 5 different landscape variables; (1) tree cover, (2) slope, (3) elevation, (4) riparian effect, and (5) streams, to measure their influence in driving H. d. goldmani genetic patterns in the coffee agroecosystem. Our results show that H. d. goldmani dispersal is limited in the coffee landscape, characterized by discrete genetic populations with limited gene flow. We found that riparian effect is the variable with the strongest correlation with the observed genetic structure. Areas close to streams in these coffee farms are steep, hard to access, and tend to be unmanaged. Our results suggest that these areas are serving as habitat or corridors, facilitating dispersal, and allowing H. d. goldmani to survive within the coffee farms. Additionally, tree cover and elevation showed some correlation with genetic distance, but it was not significant.