Pollinator behavior and visitation rates at urban orchards in St. Louis

Urban farming has emerged as an important means to decrease food insecurity as well as the environmental footprint of large-scale agriculture. The St. Louis area has seen rapid growth in community gardens and especially in community orchards, thanks to the work of Seed St. Louis. However urban harvests of orchard fruit can be extremely uneven and this may be due to variation in pollination services by insects. Pollination is well studied in the context of large scale agriculture, but less is known in the context of small scale growing within an urban matrix. In both contexts, the role of diversity of native pollinators is known to be incredibly important. As part of a larger USDA-funded collaborative project looking at pollination dynamics in urban orchards, we are testing how orchards within a gradient of urban to ex-urban environments are being served by their insect pollinators. Using extensive video sampling, we are measuring the (1) types, frequencies and durations of behavior that pollinators exhibit on flowers as well as the (2) visitation rates of pollinators on flowers within trees in a given orchard. Throughout the first two field seasons (2022 and 2023), we collected data from 10 orchard sites, visiting each orchard throughout the blooming season. We present preliminary results from these first two field seasons including types of pollinators found foraging in the orchards, common behaviors exhibited on flowers, and visitation rates at the orchards. We discuss these results in the context of urban biodiversity and of our larger project.