Insects, Trees, and Trails: effects of urbanization and vegetation on flying insect communities of temperate forests

Understanding how urbanization and human disturbances shape invertebrate communities is essential for managing biodiversity in urban green spaces. This study examined the effects of urbanization, trail proximity, and vegetation composition on flying invertebrate communities in urban and rural parks in northeastern Ohio. Flying invertebrates were sampled using fermented bait traps during summer and fall 2021, and vegetation surveys quantified tree and understory composition to assess habitat differences. We hypothesized that invertebrate communities would differ across an urban-to-rural gradient, vary with proximity to trails, and respond to differences in woody and understory plant composition. Overall, urbanization did not influence overall diversity of invertebrates but did alter community composition, favoring disturbance-tolerant taxa such as Scatopsidae, Tephritidae, and Ichneumonidae. Notably, the influence of habitat type and trail proximity on invertebrate abundance varied seasonally, suggesting that these effects fluctuate with changes in resource availability and environmental conditions over time. Rural parks supported more structurally complex, native-dominated vegetation, while urban parks had higher invasive plant cover. Overall, our results indicate that urban and rural parks contribute to biodiversity in complementary but different ways. Urban parks tend to promote generalist-dominated communities and can serve as refuges that help maintain biodiversity. In contrast, rural parks support native biodiversity and sustain key essential ecosystem functions. Maintaining structurally complex, native vegetation within urban parks may further improve invertebrate diversity and ecosystem function in urban forests.