Bug Blog

Fungicides and Pesticides May Both Spur Honeybee Decline

Fungicides and Pesticides May Both Spur Honeybee Decline

Even fungicides labeled “safe for bees” may cause problems for the beleaguered honeybee population.  Bees are directly involved in more than a third of food production globally, and are responsible for pollinating many of the most delicious foods, like fruits, and nutrient-dense ones, like oils.

Their numbers have been declining in Europe for decades, and new research conducted in New York orchards adds new facts to the growing evidence that this crisis is man-made.

Mia Park, Ph.D. and assistant professor at the University of North Dakota worked on the study as a Cornell entomology graduate student. She has authored a paper with entomology professors Bryan Danforth and associate professor John Losey that sheds light in how wild bees respond to pesticides.  Their findings were published recently by the Royal Society.

“With honeybee numbers in decline, relying on wild pollinators and encouraging the services they provide seem very important,” Park said.

The entomologist studied the health of bee populations, delineating numbers of wild bees and honeybees in each of 19 orchards in New York State in 2011 and 2012.  To test how well the bees did, they created an index of “high” to “low” pesticide use for each area.

The effects of pesticides were detrimental to both domesticated and wild bees, and the generation following the first-exposed generation suffered the most. Researchers need to conduct further research to understand the complexities of how fungicides affect bees and colonies.