Implications of rural, suburban, and urban milkweed waystation sites on monarch butterflies, Danaus plexippus

Abstract

By Hannah Dawson, Biological Sciences and Neuroscience; Adam Parlin, University of Cincinnati

Advisor: Patrick Guerra

Abstract: The population of the monarch butterfly, Danaus plexippus, has been declining due to modern stressors such as habitat destruction, urbanization, and climate change. One stressor that impacts organismal function is ambient temperature, which is usually higher in urbanized areas due to the urban heat island effect. Lower temperatures can impede flight performance, while higher temperatures lead to a more rapid depletion of lipid energy sources and a lower availability of food sources1. Increased density of canopy cover can help mitigate extreme temperatures, protecting the monarchs from extreme temperatures while maintaining optimal body temperatures needed for survival2. Conservation efforts to help provide suitable habitats and aid population growth include pollinator gardens, such as the Monarch Waystation Program. This program encourages the development of milkweed plots (waystations), to increase resource and breeding site availability for monarchs along their migration route3. The location of these registered waystations throughout the United States could have a negative impact on the growth, developmental and migratory stages of the monarchs. Using the waystation registry and raster values extracted with QGIS software, we investigated different environmental parameters that are associated with each waystation in urban, suburban, and rural locations. To investigate these parameters, we used the coordinates of the waystations and determined the surrounding habitat characteristics from canopy cover, urban imperviousness, and nighttime light pollution data. The detailed investigation of these waystation sites can contribute to better implementation practices of milkweed plots, which could bring more beneficial contributions to the migratory success and survival of the monarch butterfly.