Scarab diversity in the Algodones Dunes (Imperial Co., CA) was assessed using a series of light-bucket transects to ascertain the impact of off-road vehicle (ORV) use. We compared dune endemic scarab species on the dunes south of Hwy. 78 that receive intense ORV use and the populations on the protected dunes north of Hwy. 78. We also compared the total numbers of Coleoptera collected. Our data indicate that unprotected dunes experienced a significant decline in Coleoptera populations, diversity, and species evenness. These results demonstrate that ORV use has a severe negative impact on Coleoptera that inhabit sand dunes.