Professor The Ohio State University Columbus, Ohio
Urbanization is driving moth declines worldwide; two-thirds of common species have declined significantly since the mid 1900s. Urban greening investments such as wildflower habitats improve bee diversity, but their value for moths had not been thoroughly assessed. The goal of this project was to determine the value of small-scale urban pollinator habitats for moth conservation in a growing city. Our first objective was to compare the diversity of moths in urban pollinator habitats (0.5km2 – 12km2) to metro park grasslands (1km2 – 100km2) and turf fields. Our second objective was to assess the effects of habitat size, urbanization intensity, light pollution, and plant diversity on moth diversity using a generalized linear model. We hypothesized that metro park grasslands would support more moths than urban pollinator habitats, but that both greening investments would support more moths than turf-based landscaping. We used blacklight traps to collect moths from metro park grasslands, urban pollinator habitats, and turf fields in Franklin County, Ohio, in the summers of 2023 and 2024. We found that metro park grasslands, but not urban pollinator habitats, had significantly more moths than turf fields. We also found a positive association between impervious surface area within a 1000m radius and moth abundance in metro park grasslands and urban pollinator habitats, suggesting that both types of greenspaces can provide a refuge for moths in highly urbanized areas. The results of this study will inform greenspace management practices to improve pollinator conservation outcomes in cities.