Field realistic doses of pesticide imidacloprid reduce bumblebee pollen foraging efficiency

Bumblebees and other pollinators provide a vital ecosystem service for the agricultural sector. Recent studies however have suggested that exposure to systemic neonicotinoid insecticides in flowering crops has sub-lethal effects on the bumblebee workforce, and hence in reducing queen production. The mechanism behind reduced nest performance, however, remains unclear. Here we use Radio Frequency Identification (RFID) technology to test whether exposure to a low, field realistic dose (0.7 ppb in sugar water and 6 ppb in pollen) of the neonicotinoid imidacloprid, reduces worker foraging efficiency. Whilst the nectar foraging efficiency of bees treated with imidacloprid was not significantly different than that of control bees, treated bees brought back pollen less often than control bees (40 % of trips vs 63 % trips, respectively) and, where pollen was collected, treated bees brought back 31 % less pollen per hour than controls. This study demonstrates that field-realistic doses of these pesticides substantially impacts on foraging ability of bumblebee workers when collecting pollen, and we suggest that this provides a causal mechanism behind reduced queen production in imidacloprid exposed colonies

Statistical guidelines for Apis mellifera research

In this article we provide guidelines on statistical design and analysis of data for all kinds of honey bee research. Guidelines and selection of different methods presented are, at least partly, based on experience. This article can be used: to identify the most suitable analysis for the type of data collected; to optimise one\u2019s experimental design based on the experimental factors to be investigated, samples to be analysed, and the type of data produced; to determine how, where, and when to sample bees from colonies; or just to inspire. Also included are guidelines on presentation and reporting of data, as well as where to find help and which types of software could be useful

Guidance for summarising and evaluating field studies with non-target arthropods

Gewasbeschermingsmiddelen kunnen schadelijke effecten hebben op organismen waarvoor ze niet zijn bedoeld. Er is een richtsnoer ontwikkeld om testresultaten voor de toelatingsprocedure voor gewasbeschermingsmiddelen eenvormig en transparant aan te reiken. Het richtsnoer geldt specifiek voor veldstudies met niet-doelwit arthropoden (geleedpotigen) die boven de grond en op planten leven, bijvoorbeeld in akkers of boomgaarden. Het richtsnoer is ontwikkeld door het Nederlandse Platform voor de Beoordeling van Higher Tier Studies, waarvan het RIVM het secretariaat voert. Veldstudies kunnen een onderdeel zijn van het dossier met gegevens voor gewasbeschermingsmiddelen. Ze worden uitgevoerd als een laboratoriumstudie een risico voor het gebruik van een gewasbeschermingsmiddel aangeeft. Bij de toelatingsprocedure voor gewasbeschermingsmiddelen leveren aanvragers (meestal de bestrijdingsmiddelenfabrikanten) informatie aan het College voor de toelating van gewasbeschermingsmiddelen en biociden (Ctgb). Aan de hand hiervan beoordeelt het Ctgb of een specifiek gebruik van een middel toelaatbaar is in Nederland. De geleverde informatie betreft onder andere complexe en vaak omvangrijke informatie over niet-doelwit arthropoden. Het Ctgb laat deze studies vervolgens door verschillende externe partijen samenvatten en evalueren. Door verschillen in werkwijze kunnen de vorm van deze samenvattingen en evaluaties, en soms zelfs de conclusies, verschillen. Vandaar de wens van het Ctgb om de evaluaties en samenvattingen van veldstudies met niet-doelwit arthropoden te standaardiseren. Behalve de handleiding bevat dit rapport twee uitgewerkte voorbeelden en aanbevelingen voor het gebruik van de resultaten bij de risicobeoordeling. De risicobeoordeling houdt rekening met omstandigheden, zoals het klimaat en het gewas, die van invloed kunnen zijn op het resultaat.Plant protection products can cause harmful effects on non-target organisms. A guidance document has been developed for ensuring that the test results required for the registration of pesticides be supplied in a uniform and transparent manner. This document is specifically directed at experiments with non-target arthropods, living on the soil surface or on the vegetation, for example on arable land or in orchards. The guidance was developed by the Dutch platform for the assessment of higher tier studies, of which RIVM is the secretary. Field studies can be part of the dossier for crop protection products. Field studies are being conducted when a laboratory study indicates a potential risk of the intended use of the product. For the registration procedure, applicants, such as plant protection product producers, offer a dossier to the Dutch Board for the Authorisation of Plant Protection Products and Biocides (Ctgb). With this dossier Ctgb assesses whether a certain use of a plant protection product is allowed in the Netherlands. Complex and extensive information concerning field studies with non-target arthropods can be part of the dossier. In the Netherlands, these reports are evaluated by different evaluating institutes. Potential differences in the evaluator's methodology may lead to a lack of uniformity in the form and content of the summaries and evaluations and - occasionally - in the conclusions. This was the reason for Ctgb to ask for standardisation of the summaries and evaluation of field studies with non-target arthropods. Apart from the guidance, the report contains two elaborated examples of evaluating reports and recommendations for the use of the results of a particular field study for the risk assessment. This concerns, for example, the extrapolation of the results of a particular field study in a particular crop and region to the crop and region relevant for the registration

Bumblebee pupae contain high levels of aluminium

The causes of declines in bees and other pollinators remains an on-going debate. While recent attention has focussed upon pesticides, other environmental pollutants have largely been ignored. Aluminium is the most significant environmental contaminant of recent times and we speculated that it could be a factor in pollinator decline. Herein we have measured the content of aluminium in bumblebee pupae taken from naturally foraging colonies in the UK. Individual pupae were acid-digested in a microwave oven and their aluminium content determined using transversely heated graphite furnace atomic absorption spectrometry. Pupae were heavily contaminated with aluminium giving values between 13.4 and 193.4 μg/g dry wt. and a mean (SD) value of 51.0 (33.0) μg/g dry wt. for the 72 pupae tested. Mean aluminium content was shown to be a significant negative predictor of average pupal weight in colonies. While no other statistically significant relationships were found relating aluminium to bee or colony health, the actual content of aluminium in pupae are extremely high and demonstrate significant exposure to aluminium. Bees rely heavily on cognitive function and aluminium is a known neurotoxin with links, for example, to Alzheimer's disease in humans. The significant contamination of bumblebee pupae by aluminium raises the intriguing spectre of cognitive dysfunction playing a role in their population decline