Research summary

Pollination ecology, data mining, and sustainability of urban systems

Research in our lab over the last 20 years has focused on the community ecology and conservation of wild bees. We have shown that bee species richness, diversity, and abundance are directly and positively prairie preserves serve as a reservoir for wild bee diversity.  Furthermore, we have demonstrated that greater bee diversity leads to greater plant reproduction for important, out-crossing prairie plants.  We have also shown that the size of prairie preserves is relatively unimportant, if the floral resources are species rich – even small patches, protected or not – had equivalent bee communities. 
Our studies of bee communities in almond orchards in California show that wild bees are an important component of pollination success for almond growers and our studies at small produce farms in Iowa show that most of the pollination there is done by wild bees even when honey bees are nearby.  However, the composition of the bee community differs at farms compared to prairies, possibly as a result of differences in floral resources at these sites.

An important resource to our research program is the extensive bee collection of over 20,000 specimens collected over the past 20 years in over 70 locations.  An important aspect of collecting is that we have always identified the plant species on which a bee was caught.  We have used the associated database to “mine” for answers to questions that can only be addressed by large samples.                                                
For example, we have shown that a small group of prairie plants (like leadplant) are much more attractive to bees than expected and that these are good candidate plants for restorations designed to improve pollination services.  We are now using the data base to investigate such questions “What plants do rare bees favor?” and “What differences exist in plants visited by male and female bees of the same species?” 

Most recently, we have been investigating (with Heather Sanders in Geography) the status of urban bee communities and ways to improve it.

Our work has shown that pollinator services generally meet the demand for pollination serves in the neighborhoods in Iowa City, but that pollinator services increases with increases in socio-economic characteristics, such as income and education.  We are presently refining and expanding these preliminary studies to include detailed analyses of floral resources and bee communities in different mid-western cities.