Varroa mite on a honeybee drone. (Photo: Ethel Villalobos)
Here’s a fact that’s food for thought: Without honeybees, the plant world would produce about a third less food than it does. The adept, efficient pollination services honeybees provide are a wonder of nature, an indispensable element in the evolutionary biology of higher plants.
Until quite recently, Hawai‘i was free of the most serious honeybee pests. This allowed the Islands to host a significant queen bee production industry, exporting healthy queens to places around the world where they were needed to support bee husbandry…as well as the agriculture that depends on it. So it caused great concern in 2008 when the varroa mite—one of the greatest dangers to honeybees—was discovered on O‘ahu, causing massive bee colony losses and portending potential risks to bee-dependent crops like melons and lychee, to name only two. The varroa mite invasion then moved to the Big Island, causing distress among queen bee producers, farmers of crops such as macadamia nuts and coffee, and honey producers.
Two Plant and Environmental Protection Sciences researchers, Mark Wright and Ethel Villalobos, set out to find methods to control the scourge of the varroa mite parasites, which transmit viruses to bees. With Hawai‘i Department of Agriculture funding, they launched an all-out, statewide effort to save Hawai‘i’s honeybees. They initially concentrated on preventing movement of the mites from O‘ahu to Kaua‘i and Maui; now the scope has broadened to research on managing the ubiquitous pest and limiting its threat to our bees.
One technique they developed traps varroa mites in the drone brood, the part of the colony that male bees inhabit. By removing infested drone brood traps from hives, the mite population can be suppressed. Another significant breakthrough was registration of a new formulation of formic acid that proved to be highly effective against the mites. The treatment is quick, safe, and effective, and it likely will be approved for organic honey production.
Wright and Villalobos, and others in the CTAHR research group, continue to study mite population dynamics, determine safe thresholds for mite populations in hives, and learn more about how bees pollinate various crops. A partnership with researchers at Sheffield University in the United Kingdom is also being developed. For more information on CTAHR’s efforts to save Hawai‘i’s bees, see www.ctahr.hawaii.edu/wrightm/Honey_Bee_Home.html.