Flowering plants in gardens, agricultural fields, and residential areas often grow alongside weeds, which are controlled using herbicides. Honey bees regularly visit these places to collect nectar and pollen, raising concerns about the effects of herbicides on bees during their daily foraging.

The Impact of Glyphosate on Bee Behavior

A study conducted at the Virginia Tech University found that glyphosate—a widely used herbicide—can influence the foraging behavior of honey bees and reduce the long-term stability of hives. Glyphosate is the active ingredient in many herbicides used in agriculture and landscaping, so bees frequently encounter this substance while searching for food. The herbicide kills weeds by blocking an enzyme essential for photosynthesis. Since honey bees do not have this enzyme, glyphosate was previously considered safe for them.

Hidden Consequences of Exposure

Glyphosate exposure typically does not cause bee mortality, but researchers suggested it may lead to subtler problems. To test this hypothesis, two artificial feeders were set up: one containing glyphosate and the other without. Bees were trained to visit the feeders, and their behavior was monitored over several days.

After three days, bees exposed to glyphosate showed a 13% decrease in foraging activity. Chemical changes in the brain were also observed in these bees, changes that were not present in the control group.

Colony-Level Effects

A 13% reduction in food collection can significantly affect hive health. If an entire colony is exposed, this could lead to decreased pollination efficiency and lower honey production, threatening the survival and long-term stability of the hive. While the decrease may seem minor for a single bee, at the colony level the impact can be much more serious: fewer foraging trips mean less food in the hive, less honey, and reduced pollination of surrounding plants.

Neurochemical Changes

In the laboratory, scientists also studied brain chemicals related to bee behavior, including amino acids and neurotransmitters. They found chemical changes linked to glyphosate exposure that may explain the reduced foraging efficiency. The results indicate that glyphosate can disrupt the neurochemical balance that supports normal behavior, even if it does not cause death.

The Need for Further Research

The findings raise questions about herbicide use regulations in areas where bees may forage. To minimize unintended harm to pollinators, stricter standards, careful application strategies, and additional research are needed.

Further study is required to understand how glyphosate-based herbicides interact with honey bee biology and how these effects manifest in real-world conditions. Honey bees are among the planet’s most important pollinators, and glyphosate is one of the most widely used herbicides. Since their contact is inevitable, the consequences for bees may be far more serious than previously thought.