Urban Prairie Plots and Gardens Can Sustain Plant-Pollinator Interactions Similar to Established Rural Prairies

Abstract

Abstract. Urban prairie “gardens/plots” are gaining popularity for providing similar ecological services as remnant and restored prairies, which are predominantly found in rural areas. However, it is not known to what extent small urban prairies can sustain the plant-pollinator interactions that are vital to both the insects and the plants. The goal of our research was to examine plant/pollinator interactions in three urban prairies in southwest Missouri and compare them to rural managed/restored prairies using a visit-based approach. Urban prairies were all in Springfield, Mo. and shared similar habitat matrices (within an area of 8 km2); rural prairies were located within 68 km of urban prairies, shared similar habitat matrices to each other, and shared soil edaphic characteristics with an urban prairie. From May through August 2018 in all six prairies, we observed the five most abundant forbs in bloom, the number of pollinator visits by bees, butterflies/moths, wasps, beetles, and flies; and, pollinator fidelity from dawn to dusk. The areas observed within a prairie, hereafter “plot(s)”, were determined randomly by where at least two plants of the same species, out of the five most abundant forbs, were located. Using these criteria of observations on the five most abundant species across six prairies and four months, a total of 66 forb species were identified, with 58 of the species native to tallgrass prairies. However, only eight of the 58 native forb species were shared across urban and rural prairies. Jaccard similarity indices indicate lower similarity of the five abundant forbs within urban plots (9%) when compared to rural plots (24%), and low similarity between urban and rural plots (9%). Insect visitation varied by prairie type (rural/urban), month, and insect group; however, urban plots received 61% of the total visits compared to 39% in rural plots. Bees accounted for 5913 visits out of 10,113 visits recorded; high bee visits were similar in urban and rural plots. Insect fidelity was over 97% and did not significantly differ between rural and urban prairies. Therefore, the lack of similarity among and across urban and rural prairies in dominant species did not affect insect visitation rates or fidelity in our study. Our results suggest that establishment and management of urban prairie gardens and plots of various size may sustain the same or greater levels of pollinator services as rural prairies.