Honeybee field and semi-field trials
Since the adpotion of the EFSA guidance on the risk assessment of honeybees (2013) many field and semi-field studies failed acceptance by authorities, since they did not meet the new requirements for a high statistical test power (e.g. 7% effect size regarding colony strength, 50% effect size regarding forager mortality). We have therefore systematically analysed the reasons for these failures, which are related to high variability and high uncertainty when using standard test methods (EPPO 170, OECD 75).
We have subsequently developed new approaches and methods which considerably reduce variability and uncertainty, based on photography of adults on all frames of a hive, brood photography of the entire hive (hence the cell content of each individual cell is known, which considerably reduces the uncertainty introduced when analysing only a few hundred brood cells), automated assessment of flight activity based on video analyses, adult weighting and other methods. For comparability these new methods are conducted in addition to standard methods.
In a GLP study conducted in 2017 we have shown that these methods result in a much higher test power and that the requirements by EFSA (2013) can be reached in field or semi-field trials.
Wang, M., Braasch, T., Dietrich, C. 2020. Reduction of variability for the assessment of side effects of toxicants on honeybees and understanding drivers for colony development. PLoSONE 15(2):e0229295. https://doi.org/10.1371/journal.pone.0229295
VideoCounter is software for automated counting of honeybees or bumblebees leaving and entering their hives.
HoneybeeComplete and IndiCounter is software for the evaluation of honeybee field (EPPO 170) and semi-field trials (OECD 75).