Cities are inhospitable environments for many species. Yet bees are able to thrive in urban areas, due to the availability of floral and nesting resources in parks, vacant lots, and home gardens. In fact, some cities host bee species diversity equal to or greater than nearby agricultural areas, and at times, as high as diversity in natural areas.

In this project, we explore why bee diversity is so high in cities, approaching the question from a variety of perspectives and scales. We have been sampling bee populations in community gardens, urban farms, vacant lots, and native vegetation sites across the city since 2011. We have identified 198 bee species in St. Louis, which represents over 45% of all the species found in the state of Missouri. The vast majority of the species are found north of Interstate 44.

01.

We use body measurements, such as intertegular distance and head width, to compare the types of bee species thriving in cities. We use a continuous model, instead of discrete data categories, to understand variation between individuals with greater resolution.

02.

St. Louis is unique in its overall species diversity, particularly its diversity of pollen specialists. Typically, specialists are rare in cities due to the unpredictable availability of resources and, thus, we know very little about their role in urban areas. We compare the physical (phenotypic) and genetic features of specialist bee species across rural, suburban, and urban environments in the St. Louis metropolitan area to better understand their persistence and place in the city.

03.

When landscaped effectively, your yard can provide bees with a variety of floral and nesting resources. We collaborate with the St. Louis Audubon Society’s Bring Conservation Home program (BCH) to investigate bee diversity in residential yards. We combine bee sampling with homeowner surveys to explore how human actions, yard management practices, and neighborhood characteristics influence bee diversity.

04.

What kinds of places support bee species in a city? We characterize soil type, plant composition, resource availability, resource spatial arrangement, and surrounding land use for sites that host specialist bees to figure out what matters for bee persistence in urban areas.

05.

As more and more people inhabit urban areas, we need to better understand how urban living affects biodiversity. We study the distribution of native bee species in the Saint Louis area, looking at factors like distance from the city, biogeographic regions, and functional traits. As much as we want to know what keeps some bees in the city, we also want to know what keeps others out. Knowing why some bees are found in one area and not in another will allow us to manage habitats so that we continue to support our native bees.