Abstract
Suitable microhabitat availability for dragonfly larvae within a lotic environment influences the distribution and abundance of individuals, yet few studies have addressed this. The objective of this study was to determine how nine microhabitat variables influenced Cordulegaster diastatops occupancy within two field sites, as well as to determine if larval dragonflies have the ability to select a characteristic of their microhabitat. Microhabitat variables differed between Nelson Swamp Unique Area (NSUA) and Tioughnioga Wildlife Management Area (TWMA), as well as between occupied and unoccupied sites within NSUA only. NSUA appears to be more suitable for C. diastatops than TWMA. Relatively shallow water depth, low water temperature, and slow water velocity along with a substrate that larvae can burrow in are associated with larval presence. In a sediment choice experiment larvae demonstrated the ability to select a substrate type, and most larvae exhibited a preference for fine sand over mixed gravel.