Chronic exposure to trace lead impairs honey bee learning
Coline Monchanin1, Amaury Blanc-Brude2, Erwann Drujont2
1Research Center on Animal Cognition (CRCA), Center for Integrative Biology (CBI); CNRS, University Paul Sabatier - Toulouse III, France; Department of Biological Sciences, Macquarie University, NSW, Australia.
Ecotoxicology and Environmental Safety
|February 12, 2021
Summary
Lead exposure, even at low levels, impairs honey bee cognition and development. This trace element negatively affects learning and head size, potentially impacting pollination services.
Area of Science:
- Environmental toxicology
- Insect behavior and physiology
Background:
- Pollutants negatively impact insect development and cognition, even at sublethal doses.
- Agrochemicals are known causes of pollinator decline, but metallic trace elements are less studied.
- Anthropogenic pollutants, like lead, pose a threat to beneficial insects.
Purpose of the Study:
- To investigate the effects of chronic lead exposure on European honey bee (Apis mellifera) cognition and morphology.
- To assess the impact of field-realistic lead concentrations on honey bee learning and development.
Main Methods:
- Honey bee colonies were exposed to chronic, field-realistic concentrations of lead in their food.
- Olfactory learning performance and morphological development (head size) were measured in exposed bees.
- A correlation between head size and learning performance was analyzed.
Main Results:
- Lead consumption impaired honey bee cognition and morphological development.
- Bees exposed to higher lead concentrations showed reduced olfactory learning.
- Smaller head size in exposed bees correlated with impaired cognitive functions.
Conclusions:
- Lead pollutants, even at trace levels, significantly affect honey bee cognitive abilities.
- Lead exposure can alter crucial colony functions and compromise pollination services.
- Further research is needed to understand the full impact of metallic trace elements on pollinators.
