Neonicotinoid insecticides are systemic pesticides that persist in pollen and nectar. They are implicated in the decline of bees, butterflies, and other pollinators, causing both acute and chronic welfare effects.
Sublethal neonicotinoid exposure causes navigational impairment preventing foragers from returning to their colony, effectively causing death by starvation. Exposed bumblebees show reduced learning ability and disrupted social behaviour. Queen bees exposed during development produce fewer offspring. Chronic low-level exposure compounds natural stressors including habitat loss and parasitism. Whether insects experience their debilitation and death as suffering remains scientifically debated but precautionary welfare consideration argues for minimising exposure.