Pesticide Poisoning
Krankheiten
Poisoning by plant protection products usually shows up as a sudden, unusually high die-off in front of the entrances and in the vicinity of the affected colonies, often at several colonies of an apiary at the same time.
Poisoning by plant protection products usually shows up as a sudden, unusually high die-off in front of the entrances and in the vicinity of the affected colonies, often at several colonies of an apiary at the same time. Dead bees are also found inside the colony. Mainly foragers are affected, which is why a colony can thin out sharply within a few days, while brood and food initially remain unchanged.
Typical observations are bees unable to fly, crawling in front of the hive and showing twitching, cramp-like, or circling movements until they die. Dead bees with an extended proboscis are often found. Returning foragers are rejected at the entrance. Characteristic is that the symptoms subside again after about two to three days, because the foragers are gone, the product loses its effect, or the treated area is no longer visited, for example after rain.
Speed matters when there is suspicion. Sampling of affected bees should take place within about 24 hours, ideally through a certified bee inspector. A sufficient quantity is needed, usually at least about 100 grams of bees, corresponding to roughly a thousand bees or a honey jar full. Plant samples from the suspect stand should only be taken by the responsible authority. All samples must be kept cool and sent promptly.
The samples are examined by the bee poisoning investigation unit at the Julius Kühn Institute in Braunschweig, which carries out this task for all German states under Section 57 of the German Plant Protection Act (Pflanzenschutzgesetz). The examination is free of charge for affected beekeepers; an application form must be completed. The responsible plant protection service should be informed in parallel. The findings form the basis for claims against beekeepers' insurance and, where applicable, for civil claims.
Legally, the German Bee Protection Ordinance (Bienenschutzverordnung) provides that plant protection products classified as dangerous to bees may not be applied to flowering plants or plants visited by bees. Removing the dead bees before sampling, cleaning the hives, or immediately relocating the colonies should be avoided, as this destroys the evidence. Premature blame is likewise unhelpful: crawling bees and high die-off can also be caused by viral diseases, so only the examination provides clarity.