Bees for Development Journal 113
PRACTICAL BEEKEEPING
GOOD BEEKEEPING PRACTICE
POISONING BY PESTICIDES Wolfgang Ritter, OIE Reference Laboratory at CVUA Freiburg, Am Moosweiher 2, D79108 Freiburg, Germany PHOTO © A SPÜRGIN
Keywords: contamination, evidence, poisoning
What to do? When crawling or dead bees are suddenly found at the apiary or when there are changes in the brood, poisoning may be the reason. Good Beekeeping Practice requires immediate action to preserve the evidence. Immediate action is the only chance to identify the reason and to reduce the damage. Possible reasons for intoxication could be: • the application of pesticides in agriculture, horticulture and forestry • the malicious, criminal poisoning of bees • nectar absorption from certain forage plants.
Evaluation of indicators There are various indicators of intoxication: • increased numbers of dead bees • disturbance and biting attacks at the hive entrance • strong and sudden decrease of flight activity • changes, damage or gaps in the brood pattern • slow development of the colonies (this is mainly in cases of chronic intoxication).
Beekeepers registered with the authorities are warned to protect their colonies before pesticide applications take place confirmed, or intoxication cannot be excluded, the authority for plant protection or any other competent institution should be involved. Often their representatives are authorised to enter agricultural ground to take plant samples. These officials know the plant protection measures recommended by the district agricultural office.
The symptoms of poisoning cannot always be readily distinguished from symptoms of disease. Sometimes they are caused by the natural death of old bees. Moreover, symptoms of less common diseases can be confused with intoxication. Misinterpretation can happen when neighbouring apiaries have been poisoned and your own colonies consequently appear the same.
Preserving evidence In cases of poisoning relevant samples often have to be rejected by the institutions charged with the examination, either because of insufficient quantity of material, because the material has decayed already, or because animal and plant material were not separated properly – prohibiting the collection of evidence that is adequate to show to an insurance company or to be presented in court.
First legal opinion In many states of Germany the veterinary authorities, represented by the official bee expert, are required to give the first legal opinion. In all cases it is necessary to call an independent witness, for example a member of your beekeeping association, but never a relative. If no independent person can be reached, the police should be involved. As soon as the suspicion of poisoning is PHOTO © J SCHWENKEL
How to take samples and how to forward them correctly is described under How to do (overleaf). In Germany it is obligatory to observe these recommendations.
Action before the official result You should decide whether to stay at the location with the remaining colonies, or to move them to another place, at least for some time. As soon as the means of evidence are preserved and the scope of damage is defined, you can start cleaning. It is preferable to burn dead bees and combs. But be careful with the remaining material: it may be used again only after poisoning has been definitely excluded. Until then, the best way is to decide – with the opinion of an expert – what might be contaminated.
Action after the official result As soon as poisoning is officially confirmed, the contaminated material has to be destroyed. The hives may be concerned as well. Wood should be burnt. Other materials, for example plastic hives, have to be disposed of as hazardous waste without further risk for bees. If the responsible party is identified, you can take legal steps according to civil law and claim compensation. If you are insured against such damage, contact the insurance company which will eventually recover from the person(s) responsible.
The grass at the entrances of hives should be kept short, to make it easy to recognise serious death of bees 3
