UC Davis study reveals hidden pesticide risks inside bee colonies
Honeybees play an important role in agriculture by helping pollinate many food crops. New research from the University of California, Davis has uncovered a previously unknown way honeybee queens respond to pesticide exposure.
The study found that queen bees exposed to pesticides can transfer those chemicals into their eggs through a process known as maternal offloading. Researchers say this helps queens remove contaminants from their bodies, but it may also increase risks for developing offspring and the colony as a whole.
The research was led by Sascha Nicklisch of UC Davis and included scientists from the U.S. Department of Agriculture Agricultural Research Service (USDA-ARS) and Lawrence Livermore National Laboratory (LLNL). The findings were published in the journal Current Biology.
Scientists discovered that worker bees normally filter much of the contamination from food before it reaches the queen. However, this protective system can become less effective over time. When pesticide levels build up, queens begin moving contaminants into their eggs.
To study the process, researchers created small experimental colonies containing one queen and 60 worker bees. The bees were fed food containing low levels of pesticide methyl parathion. The team tracked how the pesticide moved through the colony.
Results showed worker bees removed about 95% of the pesticide on the first day, but filtering efficiency dropped to 86% after 10 days. This allowed more contamination to reach the queen.
Researchers warn that continued chemical buildup could affect egg development and contribute to long-term colony decline. Since honeybee colonies support pollination for about one-third of the world’s food crops, understanding these risks is important for beekeepers, growers, and pest management planners.
The team says future studies will examine how long queens can pass contamination to eggs and whether different pesticides produce similar effects.
Photo Credit: pexels-pixabay