January 26, 2026 – A new study led Ph.D. student Idan Kahnonitch under the guidance of Prof. Yael Mandelik of the Hebrew University of Jerusalem (HU) and Dr. Asaf Sadeh of the Volcani Institute in collaboration with Prof. Nor Chejanovsky of the Volcani Institute, Prof. Michelle Flenniken and Dr. Katie Daughenbaugh of Montana State University, reveals that the spread of viruses among wild bees is closely linked to the composition and availability of flowering plants, from the immediate local habitat to the wider landscape. 

Published in Ecological Applications, the study shows that viruses commonly associated with honeybees are also present in wild solitary bees, and that floral communities strongly influence their distribution. s. By surveying wild bee populations across multiple sites in a Mediterranean agroecosystem, the researchers found that both the diversity of flowers at a site and the availability of floral resources in the surrounding landscape play a key role in shaping where and when bee viruses occur. 

The team focused on mining bees (Andrena species), an important group of wild pollinators, and screened them for several widespread bee viruses. The results indicate that flowers act as shared meeting points for different pollinator species, creating opportunities for virus transmission. Certain floral communities were associated with a higher likelihood of viral presence, while landscape-level floral resource availability, extending up to one kilometer from a site, emerged as a particularly strong predictor. 

“Our findings show that flowers are not just food sources for pollinators,” the researchers said. “They also shape disease dynamics within pollinator communities. This means that decisions about habitat management and restoration, often focusing actions on the plant communities, can have unintended consequences for pollinator health if disease transmission is not taken into account.” 

Notably, the study also found evidence that viruses can be shared between managed honeybees and wild bees, reinforcing concerns that intensive agriculture and beekeeping may influence the health of native pollinator populations. While virus levels in wild bees were generally low, their presence was consistently linked to ecological conditions, especially floral composition and resource availability. 

The researchers emphasize that pollinator conservation strategies should move beyond simply increasing flower abundance or diversity. Instead, they argue for a landscape-level approach that considers which plant species are present, how pollinators share floral resources, and how these interactions may affect disease spread. 

The research was supported by the United States–Israel Binational Science Foundation and the Israel Science Foundation.

The research paper titled “Virus distributions in wild bees are associated with floral communities at local to landscape scales” is now available in Ecological Applications and can be accessed here.

Researchers:

Idan Kahnonitch1,2, Katie F. Daughenbaugh3, Na’ama Arkin2,4, Tal Erez1,5, Achik Dorchin6, Michelle L. Flenniken3, Nor Chejanovsky5, Asaf Sadeh2, Yael Mandelik1

Institutions:

  1. Department of Entomology, Institute of Environmental Sciences, Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
  2. Department of Agroecology and Natural Resources, Newe Ya’ar Research Center, Agricultural Research Organization–Volcani Institute, Ramat Yishay, Israel
  3. Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, Montana, USA
  4. The Mina & Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan, Israel
  5. Department of Entomology and Nematology, Institute of Plant Protection, Agricultural Research Organization – Volcani Institute, Rishon Letzion, Israel
  6. The Steinhardt Museum of Natural History, Tel Aviv University, Tel Aviv, Israel