Edge effects detected at the level of order

Studies of how forest fragmentation affects insect abundance and community structure not only reveal the basic ecological mechanisms that shape the distribution of insects across different habitat types, they are key to informing conservation efforts and land management practices. The majority of studies of edge effects on insects often focus on one or two species of interest, mainly endangered or bioindicator species, and broader surveys of abundance and diversity at the level of Order and Family are lacking. During the 4-week Field Entomology course at Washington and Lee University in Lexington, Virginia, students used pitfall traps, quadrats, and sweep netting along transects to assess insect abundance and diversity in two sites in the fragmented forest in the back of campus. Site 1 was in an old power line cut that is now heavily used as a running trail, and site 2 was in the adjacent forest interior. Results show that Coleoptera and Hymenoptera are significantly more abundant in the interior habitat whereas Diptera were more often found in the power line cut. This study shows that insect abundances on the level of Order differ across edges despite the large diversity of feeding and mating behaviors within an Order, and underscores the importance of maintaining diverse habitats in managed lands.