Queen bees have a disturbing way to survive pesticides

Queen bees employ an unusual tactic to combat the effects of pesticides, a discovery that sheds new light on the complex dynamics of colony health. Research led by the University of California, Davis, reveals that when honeybee queens are exposed to pesticides over time, some chemicals can accumulate in their bodies and then be transferred into their eggs through a process called maternal offloading.

This revelation, published in Current Biology, is the first of its kind in honeybees. Senior author Sascha Nicklisch explains that this defense mechanism allows queens to rid themselves of harmful substances. The study, a collaborative effort with Lawrence Livermore National Laboratory and the U.S. Department of Agriculture's Agricultural Research Service, utilized nanocolonies to track how pesticides move through the colony.

By day 10, pesticide filtration by worker bees had dropped from 95% to 86%, suggesting worker bees' capacity to protect queens can be overwhelmed. This finding has implications for beekeepers, growers, and integrated-pest-management planners, especially during periods when bees are actively foraging or colonies are expanding. The study's lead author, Angela Encerrado-Manriquez, notes that worker filtration capacity may be overwhelmed, leading to queens offloading toxic burden to their eggs.

The research underscores the need for further investigation into how long queens can continue transferring contaminants into their eggs, the long-term consequences for the colony, and whether the process varies with different pesticides.