ABO-Projekt: Auswirkungen von mit Clothianidin saatgutbehandeltem Raps (Brassica napus L.) auf Bienen – Überwinterungserfolg von Honigbienenvölkern (Apis mellifera L.) aus zwei Jahren Feldversuchen

"The ABO-project aims to investigate potential risks of oilseed rape grown from clothianidin-treated seed to honeybees as well as other pollinators (bumblebees, solitary bees). In spring 2014 and 2015, bees were exposed to flowering oilseed rape (OSR) on five locations for three weeks. Honeybee colonies (Apis mellifera L.) were regularly checked for different parameters (mortality, activity, weight, colony development, pesticide residues in nectar and pollen, parasite loads). Here we show preliminary data for overwintering success of honeybee colonies after the winters 2014/2015 and 2015/2016. For each year and each location, two comparable oilseed rape fields (Brassica napus L.) were selected. One field was cultivated with OSR grown from clothianidin-treated seed (seed coating “ELADO®”, containing 10 g clothianidin per 1 kg seed) and one field with OSR grown from seed without clothianidin seed coating as a control. Four honeybee colonies were placed adjacent to each flowering oilseed rape field. Colonies derived from sister-queens from the year before and were of similar strength (10000 bees +/- 2000 bees) at the beginning of the season. Preliminary data show no differences between treatment and control hives in overwintering success in both years."