Coleoptera Collected Using Three Trapping Methods at Grass River Natural Area, Antrim County, Michigan

Overall, 409 Coleoptera species (369 identified to species, 24 to genus only, and 16 to subfamily only), representing 275 genera and 58 beetle families, were collected from late May through late September 2017 at the Grass River Natural Area (GRNA), Antrim Coun-ty, Michigan, using baited multi-funnel traps (210 species), pitfall traps (104 species), and sweep nets (168 species). All three collecting methods were used in three distinct habitats: a rich conifer swamp (cedar), near the edge of a red pine plantation (pine), and within a mesic northern hardwood forest (hardwoods). Additional collections were made along two trails and in an open field by sweep netting only. Of the 409 species, 322 were collected in one or more of the cedar, hardwoods, and pine habitats, and 152 were collected along the two trails and the grassland site. Of the 322 species collected in the three main habitats, 40 species (36 genera and 14 families) were collected in all three habitats, 105 species (80 genera and 32 families) were collected in the cedar, 176 (131 genera and 38 families) in the hardwoods, and 199 (158 genera and 47 families) in the pine habitats. With respect to adult seasonal activity, 21% of the 409 species were first collected in May, 40% in June, 23% in July, 10% in August, and 6% in September. Of the 210 species collected in funnel traps, 144, 123, and 114 species were collected, respectively, in traps baited with α-pinene, ethanol, or ipsenol. Diversity indices were calculated for the funnel trap data by site and lure. Overall, 32 of the 409 species were considered exotic to North America, and 18 were considered new state records for Michigan. In addition, 16 species of aquatic beetles (12 genera in 5 families) were identified from GRNA stream samples collected during 2013–2019