Pollinator Week: Native Bee Research

Pollinator Week: Native Bee Research

Every year, we celebrate National Pollinator Week by sharing stories of researchers and native bee advocates and their work with our native pollinators. Below are the stories that we shared and we hope that they inspire you and give you ideas for how we can all work together to take care of our native bees and other pollinators.

Dr. Elaine Evans, Assistant Extension Professor, University of Minnesota

My work focuses on bee conservation. My recently finishedPh.D. research focused on bees in agricultural areas in the Northern Great Plains. I found that grasslands, wooded areas, and crops providing bee forage supported wild bee diversity. Farmers and other land managers can help bees by growing more crops that bees use for forage, retaining or creating shelter belts, and taking advantage of set-aside programs to create grasslands.

You can find out more about this by watching my TedX talk on Farms for Bees. This year I will start my 11th year of surveying bumble bees in parks in Minneapolis and St Paul in search of the rusty patched bumble bee, recently listed as an endangered species, and other declining bumble bee species. Everyone can help the efforts to track these rare and declining bumble bees by taking photos and submitting them to Bumblebee Watch.  

Claire Kremen, Professor, Department of Environmental Science, Policy and Management; University of California, Berkeley 

This year we've been investigating how to diversify farms so that they can support wild pollinators that in turn support crop production, we call this "ecological intensification". It uses ecological principles to enhance production while supporting and sustaining the underlying organisms (beneficial soil microbes, pollinators, predators of crop pests, etc.) that provide key processes important for crop production. For the coming year, we are starting to look at how soil health and pollinator health may be interrelated. Specifically, when farmers use practices than enhance beneficial fungi (arbuscular mycorrhizal fungi) in the ground, how does this affect the nectar and pollen quality of the crop? Does this make crops more attractive to pollinators, potentially enhancing pollination?

Expert advice: The most important thing is to plant a diversity of pollinator-attractive plants in your garden, and not to use pesticides, If possible, try to buy plants from nurseries that do not use neonicotinoid pesticides. Find pollinator plant lists here.

Heather Grab, Postdoctoral Researcher, Poveda Lab, Department of Entomology; Cornell University

The lake reeds we ordered this spring are part of a new project following up on some of the results from my Ph.D. work. One of the things we are finding is that bees collected from simple, highly agricultural landscapes are much smaller than their counterparts in more diverse landscapes.

There could be many reasons for this "Lilliputian" effect including lack of sufficient quantity or diversity in their diet, exposure to pesticides, or even selection acting to optimize body size to local conditions. My previous work focused on small ground-nesting bees in the genus Andrena. Their nests are extremely difficult to locate so trap-nesting bees seemed like the ideal research system for my postdoctoral work.

If I had to make a recommendation for gardeners, I would say plant as many native perennials as you can fit. For farmers, I would say to stagger the bloom times of your pollinator-dependent crops. This will not only increase pollination rates and yield but also provide more consistent floral resources for crop pollinators.

Joshua Campbell Ph.D.; Postdoctoral Research Associate, Department of Entomology and Nematology; University of Florida

Dr. Campbell’s long-term work has researched the pollinators of endangered plants and how changes in the landscape affect bee populations. An interesting example of research that stretched over a decade occurred in North Carolina. Dr. Campbell monitored bee biodiversity after prescribed burns, which are lower temperature fires that typically burn away leaf litter and understory brush. The first study on how these prescribed fires affected bees was conducted 15 years ago and they observed an increase in ground-nesting bee abundance and diversity shortly after the prescribed burns. This boost in bee populations is due to an increase in the understory floral blooms and the simple fact that the burn removed leaf litter, exposing soil for ground-nesting bees to build nests. Twelve years later Dr. Campbell was able to return to the same sites and compare results from the initial response to multiple rounds of prescribed burns applied over a 15 year period. Surprisingly, there is a repeated and continued success in bee populations after consistent prescribed burns, which points to the benefits arising not just from the initial burn.

Dr. Campbell’s recent work is studying the crop pollination of blueberries in Florida, which has the unique problem of blueberry blooms opening in January and February, much earlier than other parts of the country. The only bees flying this early in the year are (managed) bumble bees, honey bees, carpenter bees, and the southeastern blueberry bee. The research team is caging blueberry plants and only allowing managed bumble bees to enter. So far, the bumble bee’s pollination success in these cages is comparable to the honey bees. There is a 60-70% increase in blueberry production within cages stocked with bumblebees versus blueberry plant cages without any bees present.

Similar cages are being placed on watermelon plants in Florida to observe managed bumble bees. Florida watermelon are visited by 32 species of bees and about 28 are ground-nesting species. The team is also studying small wildflower plots near agricultural fields and asking do they attract native bees to the fields?

Next up are plans to work through the Museum of Natural History and collaborate with an energy company to explore bee abundances and diversities within their right of ways for power lines. This research will investigate vegetation management practices and how to best support pollinators. Utility companies have recently shown increased interest in managing their right of ways as pollinator habitat.

Expert Bee Advice: Most bee species nest in the ground and this means that plowing land is not beneficial for bees. If you have a large garden, no-till practices would be best. Ground-nesting bees have a variety of preferences but they all need access to soil that they can nest within without much disturbance.


Leif Richardson, Postdoctoral Research Associate at University of Vermont; Senior Ecologist, Stone Environmental

Through a specialty crop grant from the USDA, Dr. Richardson is studying native bees and their importance as pollinators of apples, blueberries, and raspberries. The grant is supporting the research of bees in the Osmia (mason bee) and Bombus (bumblebee) genera at 20 different farms across Vermont. For the Osmia study, the research team is using trap nests in 8mm, 6mm, and 4mm hole sizes. The aim is to rear populations of native bees, propagate them and move them to nearby farms. Local native bees are best because they have the proper genotype and there are disease concerns from managed bees that have been raised elsewhere. The study’s bee houses have been designed to have the right number of nesting holes in order to have a good success rate for increasing native bee populations. Cocoons of wild bees will be managed to overwinter in a variety of ways based on what each species dictates.

Another grant is funding the study of polyester bees in the Colletes genus and their pollination of apples and blueberries. Colletes are ground-nesting bees that are active from April to June, and they nest in large aggregations in sandy soil and their underground nests are excavated in the fall. Adult bees hibernate as pupae and after harvest, these young bees are repacked in dense sand to continue hibernation over winter. The bees are managed similarly to the western states alkali bees, which are ground-nesting bees that pollinate alfalfa fields.

Expert Bee Advice: There is a distinction in the role of honey bees and native bees and native bees are doing the majority of pollination on farms regardless if the farm brings in honey bees or not. Native bees are doing the bulk of pollination and are not getting recognition for their work. Our food supply is linked with native animals and we need to think about the bees that are involved in pollinating our food. We should wonder if the bees are wild and abundant, based on the landscape, and what kind of pest management tools are used. 

Erin Krichilsky, Undergraduate Senior of Entomology, Cornell University

During my time at Cornell I have had the incredible opportunity to be a member of the Danforth lab. Since I entered the lab 2 years ago, I have received funding from various sources within the College of Agriculture and Life Sciences (CALS). These include the Jane E. Brody Undergraduate Research Award and the S. Ann and Robert R. Morley Research Grant. These grants, and the amazing mentorship of the Danforth lab has allowed me to since pursue an independent project.

I work closely with Dr. Heather Grab. The project focuses on the bee fungal pathogen, Ascosphaera, commonly known as chalkbrood. In this project, we investigated the presence of Ascosphaera within the hornfaced mason bee, Osmia cornifrons. The O. cornifrons were seed bees that were set out and collected from 17 orchards in the Finger Lakes region of New York. We recorded the types of pesticides sprayed in the orchards and the types of landscape that surrounded them. We determined the presence of Ascosphaera by using both visual detection and molecular techniques. By using molecular techniques we were able to determine the species of Ascopshaera present in O. cornifrons. We then explored potential relationships between the pesticides and landscape data and the presence of Ascosphaera.

We also had the opportunity to mentor an Ithaca high school student, Madelyn Kuo, during the Spring semester. She helped us by measuring the intertegular distance of the bees in the study to see if there was a relationship between size and Ascosphaera presence.

We found really interesting and exciting results. During the spring semester I was able to present this research at the Scientista symposium in NYC and at the Cornell Undergraduate Research Board Spring Symposium on the Cornell campus. I was also able to present this work for the Cornell Entomology department at the final Jugatae seminar of the semester.

Plans for the future: We are currently conducting a bioassay with O. cornifrons to further explore interactions between fungicides and Ascosphaera. This is a follow-up study from the results we found in the Spring. We are excited to see what the experimental aspect of this project will show us.

I plan to finish this project and turn it into a Senior Thesis before I finish my undergraduate career (December 2017). There’s still lots of hard work to do, but we ultimately hope to turn this project into a publication.

Expert Bee Advice: Bees truly embrace the adage, small but mighty. I think the first step towards benefiting pollinators is recognizing their intricacies. We should be working to both better understand that and how to serve it in our ecosystem.
Simple steps can truly form an impact; from planting native flowers, to reading accurate sources, remember that knowledge is power… and bees are powerful.

Thanks: I am so grateful to all the time and mentorship Heather Grab has devoted to me and this project, all while finishing up her Ph.D. (which happened this Spring). To Mary Centrella who was instrumental in the experimental design and inspiration of this project. To Bryan Danforth for accepting me into the lab and allowing me to pursue this. And to the entire Danforth lab for their endless support and guidance throughout this process. It has by far been one of my most valuable experiences at Cornell and in life.