Anthony Zhao, University of Maryland. Species Diversity and Community Similarity of Carrion Beetles Along an Urban-Rural Gradient. Mentor: Dr. Jason Munshi-South Abstract: Habitat fragmentation resulting from urbanization is a major threat to carrion beetle (Coleoptera: Silphidae) communities in the Northeastern United States. This study examined species richness, diversity, and community similarity of carrion beetles along an urban-rural gradient in the New York City metropolitan area. Carrion beetles were trapped and collected at 12 field sites. We captured eight species in total, the most common being Nicrophorus tomentosus, Oiceoptoma noveboracense, and Nicrophorus orbicollis. O. noveboracense was found predominantly in urban and suburban areas, earlier during the summer. Necrophila americana was only found in suburban and rural areas later during the summer, Nicrophorus defodiens predominantly in rural areas, and Nicrophorus sayi only in rural areas. We calculated both species richness and Simpson’s reciprocal diversity index for all sites, and examined their association with urbanization using linear regression. We also examined community similarity between all pairs of sites. Additionally, the carrion beetle community at the Louis Calder Center in Armonk, New York was compared with the community observed in a past survey. Urbanization was not significantly associated with either species richness or diversity. We determined that community similarity was not strongly associated with position along the gradient, and it showed some variation between habitat groups. We also reported that the carrion beetle community at the Calder Center has changed considerably, likely as a result of increased local development. These findings indicate that urban forest fragments may be able to support relatively high carrion beetle diversity, and can be used to guide future studies in urbanization and arthropod communities. .