It's all the buzz!

The California Honey Festival, set Saturday, May 7 from 10 a.m. to 5 p.m. in downtown Woodland, will focus on honey, bees, plants and pollination.  

"UC Davis will have a slimmed down version this year," said Amina Harris, director of the UC Davis Honey and Pollination Center at the Robert Mondavi Institute, and a co-founder of the event.  Launched in 2017, the Honey Festival hasn't been held since 2019 due to the COVID-19 pandemic. Some of the events on tap Saturday: 

• The UC Davis Honey and Pollination Center will showcase its honey tasting wheel and offer free honey tasting.
• The California Master Beekeeper Program will staff two educational booths. Visitors can examine a bee observation hive, check out the beekeeping equipment and peer through microscopes. Kids' activities are also planned. 
• The Bohart Museum of Entomology of the UC Davis Department of Entomology and Nematolgoy will showcase bee diversity in its specimen drawers. Its live "petting zoo" will include Madagascar hissing cockroaches and stick insects (walking sticks) that folks can hold,  said Tabatha Yang, education and outreach coordinator.
• The UC Davis Arboretum and Public Garden will address pollinator needs and gardening.
• The Woodland Public Library will offer a children's reading hour.
• Uncle Jer's Traveling Bee Show will provide educational performances.
• The UC Davis Bookstores booth will contain honey, books, and other gifts for sale.
• Visitors can don a bee costume and get their picture taken in the UC Davis Pollination Park, a collaboration with the UC Davis Arboretum and Public Garden. 

Harris said the festival will include live music, a beer and mead garden, and about 100 vendors selling everything from food to plants to arts and crafts. Admission to the festival is free. The first festival drew some 30,000 visitors.

An after-party is planned at The Hive, owned by Z Specialty Food, Woodland. Advance registration is required. Access https://zspecialtyfood.com/event/california-honey-festival-after-party/

(Note: This year the UC Davis Bee Haven, operated by the UC Davis Department of Entomology and Nematology, won't be able to participate due to scheduling conflicts, said academic program management manager Christine Casey.)

Scott McArt, an assistant professor in the Cornell University's Department of Entomology. will speak on "Pesticide Risk to Pollinators: What We Know and What We Need to Know Better" at the Wednesday, May 4 virtual seminar hosted by the UC Davis Department of Entomology and Nematology.

The seminar begins at 4:10 p.m. The Zoom link: 
https://ucdavis.zoom.us/j/99515291076

"The use of synthetic chemical pesticides is central to current agricultural practices worldwide," McArt says in his abstract. "But what is the cost to wildlife via non-target exposures? This talk will summarize when there's risk to bees, when there isn't, and what types of research are most likely to influence farmers, regulatory agencies, and policy makers."

McArt, who joined the Cornell faculty in 2017, focuses his research on pollinator health and ecology. His areas of expertise include disease ecology, ecotoxicology, community ecology, chemical ecology, and plant-pollinator interactions. He  maintains his lab research site at https://blogs.cornell.edu/mcartlab/. 

"Research in our lab focuses on the impact of pesticides, pathogens, and habitat on honey bees and wild bees," he writes on his website. "We are particularly interested in scientific research that can inform management decisions by beekeepers, growers and the public. Current research projects include: 1) Understanding pesticide exposure and risk to bees in multiple land management contexts, 2) Combining empirical data with network modeling to understand pathogen transmission in complex plant-pollinator networks, and 3) Understanding how habitat enhancements (e.g., flowers at solar power sites) impact pollinator populations and the services they provide to agriculture."

McArt's duties at Cornell also include director of the Cornell Chemical Ecology Core Facility, and associate curator of the Cornell University Insect Collection.

He writes a monthly column, Notes from the Lab, in American Bee Journal; each month he summarizes scientific publications for a non-scientific audience. "The goal is to make the emerging pollinator health science more approachable and relevant to beekeepers," he says.

He is also a member of the New York State (NYS) Beekeeper Tech Team, which works directly with NYS beekeepers to improve honey bee health, reduce colony losses, and increase profitability of the state's beekeeping industry: https://pollinator.cals.cornell.edu/nys-beekeeper-tech-team/

In addition, McArt coordinates such beekeeping workshops as "Introduction to Honey Bee Queen Rearing" and "Honey Bee Biology and Disease Management for Veterinarians" and engages with growers regarding pesticide risk to bees and creating pollinator-friendly habitat. His extension materials are onsite.  

When asked "What gets you out of bed in the morning?" during a new faculty interview, he responded "Most of the factors contributing to declines in bee health (pesticide exposure, lack of floral resources, disease, inadequate management practices) are preventable. With targeted research efforts and educated stakeholders, regulatory agencies and public, we can make a difference."

McArt holds a bachelor of arts degree in environmental and evolutionary biology (2001) from Dartmouth College, Hanover, N.H., and a master's degree in biological sciences (2006) from the University of Alaska, Anchorage. He received his doctorate in entomology in 2012 from Cornell University. He served as a USDA-NIFA (National Institute of Food and Agriculture) postdoctoral fellow at the University of Massachusetts, Amhurst, in 2014, and then as a research scientist at Cornell from 2014 to 2017, before joining the Cornell faculty. 

Nematologist Shahid Siddique, assistant professor, UC Davis Department of Entomology and Nematology, is coordinating the spring seminars. For Zoom technical issues, contact him at ssiddique@ucdavis.edu.

(See complete list of spring seminars.)

A UC Davis entomologist, formerly of the Harvard University Herbaria, is among the scholars and artists who helped spearhead the newly created Harvard Museum of Natural History's “In Search of Thoreau's Flowers: An Exploration of Change and Loss," hailed as an examination of the natural world and climate change at the intersections of science, art and history. It opens to the public starting May 14.

Emily Meineke, assistant professor of urban landscape entomology, UC Davis Department of Entomology and Nematology, helped launch the project in 2017 when she was a postdoctoral fellow at the Harvard University Herbaria.

The exhibit in Cambridge, Mass., is “an immersive multidisciplinary experience that marries art and science through a modern artistic interpretation of Henry David Thoreau's preserved plants,” said Bethany Carland-Adams, a public relations specialist with Harvard Museums of Science and Culture (HMSC). 

Henry David Thoreau (1817-1862), naturalist, author and philosopher and a 1837 graduate of Harvard University, is best known for his book Walden. Removing himself from social life, he settled into a cabin by Walden Pond, Concord, Mass., from July 1845 to September 1847 to immerse himself in nature. 

The 648 plant specimens that Thoreau donated to the museum form the foundation of the exhibit. "He was prolific in his practice of collecting botanical samples and plants are important indicators of how our world is responding to climate change," Carland-Adams said in a press release.  

Meineke, who joined the UC Davis faculty in 2020, served as a postdoctoral fellow at Harvard University Herbaria from 2016 to 2019, including a National Science Foundation-sponsored fellowship there in 2017.  She holds a doctorate in entomology from North Carolina State University (2016), Raleigh, where she wrote her dissertation on “Understanding the Consequences of Urban Warming for Street Trees and Their Pests.” 

“I was one of the original creators of the exhibit, along with the other scholars and artists listed on the program,” Meineke related. “We started thinking about it in 2017 as a group. I served as the primary scientific liaison with the artists, helping them interpret the most interesting data that arose from studies of Thoreau's specimens.” 

“Ultimately, we landed on using visual media and portraits to highlight the decline of local plants," Meineke said. "Those art works are now central to the exhibit, as are Thoreau's actual specimens provided by Harvard and descriptions of the discoveries made possible by his work as a naturalist.”

The exhibit includes Meineke's work on insect herbivore-plant interactions over the period of recent climate change as one type of research made possible by Thoreau's plant collections. 

 “The digitization of the specimens, and others in the Herbaria collection, are now allowing broader access to scholars and citizen scientists, in turn welcoming new domains of scholarship,” Carland-Adams noted. "The exhibition invites visitors to experience emotionally resonant connections to the profound loss of natural diversity caused by human-induced climate change. The exhibition urges us to ask, 'What do Thoreau's findings tell us about what plants are winning, and what plants are losing, in the face of climate change today?'"

Charles Davis, curator of vascular plants at Harvard University Herbaria, teamed with Marsha Gordon, a North Carolina State University professor, and Meineke to frame plans for the exhibit, collaborating with artists Leah Sobsey and Robin Vuchnich, both university faculty members, to shape the vision. 

Vuchnich, an assistant professor at North Carolina State University, leveraged the digitized specimens to craft an immersive experience in the gallery theater. It includes animations of the herbarium images and soundscapes recorded at Walden Pond.

Sobsey, an associate professor of photography and director of the Gatewood Gallery at the University of North Carolina, Greensboro, focused on cyanotype, a 19th-century photographic process that relies on UV light to create a distinctive Prussian blue tone. Sobsey utilized all 648 digitized Thoreau specimens, and created a wallpaper comprised of original cyanotypes and digital imagery, relating a story of the survival and decline of plant specimens.

In the news release, HMSC executive director Brenda Tindal emphasized the significance of Thoreau's observations and his indelible impact on society..."Thoreau's clarion call compels us to intentionally lean into our surroundings and learn from nature—and by extension, the global community to which we all belong.”

Visitors will gain "a deeper understanding of how different plant species respond to environmental factors, within and between species," Carland-Adams shared. "For instance, some plants are sensitive to temperature, while others show less or no sensitivity. This type of data drives the exhibition's animations and directly impacts our daily lives in the context of agriculture and food production."

The Thoreau exhibit may also become a traveling exhibit.

The HMSC mission "is to foster curiosity and a spirit of discovery in visitors of all ages by enhancing public understanding of and appreciation for the natural world, science, and human cultures," according to its website. "HMSC works in concert with Harvard faculty, museum curators, and students, as well as with members of the extended Harvard community, to provide interdisciplinary exhibitions, events and lectures, and educational programs for students, teachers, and the public. HMSC draws primarily upon the extensive collections of the member museums and the research of their faculty and curators."

Resources:

• Harvard Museum of Natural History Website
• Press Release
• Podcast: Listen to the HMSC Connects! featuring host Jennifer Berglund, entomologist Emily Meineke, and artists Robin Vuchnich and Leah Sobsey. (Read the transcript) 

Bumble bees prefer foraging on flowers that contain yeast, but does yeast benefit bumble bee survival and reproduction?

Yes, according to UC Davis community ecologist and doctoral candidate Danielle Rutkowski and her colleagues in their newly published research in the Royal Entomological Society's Journal of Ecological Entomology.

The research, “Bee-Associated Fungi Mediate Effects of Fungicides on Bumble Bees,” provides direct evidence that fungi can benefit both survival and reproduction in two species of bumble bees, Bombus vosnesenskii,  and B. impatiens. The research also suggests that yeast, commonly found in the gut of bumble bees, may be more important than originally thought.

“Bumble bees are important pollinators that face threats from multiple sources, including agrochemical application,” said Rutkowsi, the lead researcher-author. “Declining bumble bee populations have been linked to fungicide application, which could directly affect the fungi often found in the stored food and gastrointestinal (GI) tract of healthy bumble bees.”

 “I tested if fungicides commonly applied in orchard systems affected yeasts and the health of their bee hosts, and if feeding those bees their fungi after fungicide exposure could rescue them,” said Rutkowski, who studies with major professors Rachel Vannette and Richard Karban, community ecologists in the Department of Entomology and Nematology.

“Bombus vosnesenskii (commonly known as the yellow-faced bumble bee), is native to California and we reared colonies of it from wild-caught queens,” Rutkowski said. “In this species, we observed strong negative effects of fungicide and the ability of bee-associated fungi to rescue bees from these negative effects. The other species, Bombus impatiens, is native to the eastern United States, but is commonly produced and sold commercially for pollination. In this species, we did not find any negative impacts of fungicide, but the addition of yeasts was very beneficial for bee survival and offspring production.” 

Vannette, a co-author of the paper, pointed out: “We knew that bumble bees in the field prefer foraging on flowers that contain yeasts, and that bumble bees have yeasts in their gut; but didn't know how those yeasts affected bees, or how fungicides affected yeast-bee interactions.”

“Although most previous work on bee microbiomes has focused on bacteria and their role in bee health, Danielle's work suggests that yeasts --which are commonly found in association with bumble bees--may be more important than previously thought,” Vannette said. “This has been hinted at in the literature but rarely tested directly.” 

Rutkowski examined the interactive effects of the fungicide propiconazole and fungal supplementation on the survival, reproduction and microbiome composition of microcolonies (queenless colonies) using the two species.

Both B. vosnesenskii and B. impatiens benefitted from fungal addition but in different ways. fungicide exposure decreased survival in B. vosnesenskii, while fungal supplementation mitigated fungicide effects. For B. impatiens, fungicide application had no effect, but fungal supplementation improved survival and offspring production.

The research also shows that for at least some bumble bee species, fungi can mediate the effects of fungicides on bee health. “In other words, the fungicide tested here (propiconazole) may harm the bee-associated fungi rather than the bees themselves, and restoring the yeasts (a type of fungus) can mitigate effects on bee survival,” Rutkowski said. 

 “Because the effect of fungicides on yeasts and bees takes a few weeks to observe, it is not detected in short term LD50 trials,” Vannette said, “and therefore could be an unrecognized threat to bumble bees and their symbionts.”

Other co-authors of the paper are entomologist Eliza Litsey and environmental scientist Isabelle Maalouf. 

More research is planned to determine the mechanism by which yeasts can affect bee health, and which fungicides affect bee-associated yeasts. 

 “I'm currently working on a project to determine the mechanisms behind the positive effects of yeast addition that we observed,” Rutkowski said. “In some bees and other insects, fungi can produce nutritionally important compounds for their host, and I'm currently trying to determine if this is the case for bumble bees as well.” 

“Additionally, I'm planning on following up some of the interesting results on differences between bumble bee species by determining how associated microbial communities differ between wild and commercially-reared bumble bees,” Rutkowski said. “In this current paper, we found that the fungal communities associated with the commercially-sourced bees were less diverse and less abundant, and I'm hoping to determine if that's a common pattern.” 

Rutkowski, who joined the UC Davis doctoral program in 2018, won the President's Prize (first-place) in her category for her graduate student research presentations at the 2017 and 2021 Entomological Society of America meetings. A 2018 graduate of Cornell University, summa cum laude, she holds a bachelor of science degree in entomology and biological sciences, with a concentration in ecology and evolution.

Rutkowski's research drew support from her three-year USDA National Institute of Food and Agriculture grant.