Human disturbance and habitat size do not affect mammal species richness
Aurora Robert
From changes in their behavior to declines in population size, mammals are frequently influenced by human disturbance. In the presence of human disturbance, mammal community composition can change, and species diversity may decrease. At the local scale, human disturbances can be lasting (e.g., the removal of forests creating open and edge habitats) or temporary (e.g., hiking, field maintenance, vehicle traffic). Human activities also decrease the habitat size available to mammals. In this study, we investigated whether habitat size and human disturbance affect species richness in Upstate South Carolina. We predicted species richness would be lower in areas with higher temporary human disturbances (THD) and in more open habitats. We also predicted that smaller available habitats would have a lower species richness than larger available habitats. To test our predictions, we collected images using camera traps in various stations across four sites. We calculated the area of each site using GIS mapping. Each station was classified as forest, open, or edge habitat and given a THD score. The mammal species in each image were identified, and we used the Chao 1 estimator to determine species richness for each station and site. We found no significant difference in the mean species richness between the high, low, and no THD stations. We also detected no difference in mean species richness between the three habitat types. Additionally, we found no significant relationship between species richness and habitat size. Overall, local human disturbance and small habitats do not significantly decrease species richness in mammal communities at our sites. This suggests that the mammal species we observed in Upstate South Carolina are tolerant to both local disturbance and increased habitat fragmentation. In future studies, we will use GIS to investigate the effects of lasting and temporary landscape-level human disturbances on mammal communities.
Aurora Robert is an environmental science major at Lander University. She plans to pursue a career in environmental conservation.