Honeybee colonies unwittingly invite destruction from invasive beetles

GAINESVILLE, Fla. — Although its link to a near-epidemic honeybee die-off has not been demonstrated, researchers have unraveled a bizarre love-hate triangle of bees, yeast and an invasive species of beetle that has been wrecking hives around the globe.

Best of all, this story may have a happy ending.

The scenario is relatively straightforward. When a beehive undergoes even the smallest amount of stress — such as inclement weather or a lack of pollen in the area — the bees release a pheromone to spread the word in the hive that tough times may be ahead.

The problem is that the small hive beetle, an invasive species from Africa, is strongly attracted to the pheromone. The insect is actually 100 times more sensitive to the chemical than the bees themselves.

These beetles carry a type of yeast in their gut that breaks down pollen. As they begin to infest a hive, the yeast spreads out from the beetles’ feces and causes some of the pollen to ferment.

The fermentation alarms the bees — who then send more of the stress pheromone — which draws the attention of even more beetles. Eventually the bees give up, and the colony abandons its hive.

However, this doesn’t have to be the case, thanks to researchers from the United States Department of Agriculture (USDA), the University of Florida’s Institute of Food and Agricultural Sciences (IFAS), Pennsylvania State University, and the International Centre of Insect Physiology and Ecology in Nairobi, Kenya.

In the April 30 early edition of the journal Proceedings of the National Academy of Sciences, the researchers describe this three-pronged relationship and a simple way of luring the beetles away from a hive using chemicals similar to the bee stress pheromones.

To inquire about these findings, contact:

Peter E. A. Teal, USDA and IFAS research leader, 352-374-5730, pteal@gainesville.usda.ufl.edu

Richard T. Arbogast, USDA and IFAS research entomologist, 352-374-5719, Terry.arbogast@ars.usda.gov

James H. Tumlinson, USDA and Penn State research entomologist, 814-863-1770, jht2@psu.edu