title: Seed coating with a neonicotinoid insecticide negatively affects wild bees.
abstract: Understanding the effects of neonicotinoid insecticides on bees is vital because of reported declines in bee diversity and distribution and the crucial role bees have as pollinators in ecosystems and agriculture. Neonicotinoids are suspected to pose an unacceptable risk to bees, partly because of their systemic uptake in plants, and the European Union has therefore introduced a moratorium on three neonicotinoids as seed coatings in flowering crops that attract bees. The moratorium has been criticized for being based on weak evidence, particularly because effects have mostly been measured on bees that have been artificially fed neonicotinoids. Thus, the key question is how neonicotinoids influence bees, and wild bees in particular, in real-world agricultural landscapes. Here we show that a commonly used insecticide seed coating in a flowering crop can have serious consequences for wild bees. In a study with replicated and matched landscapes, we found that seed coating with Elado, an insecticide containing a combination of the neonicotinoid clothianidin and the non-systemic pyrethroid β-cyfluthrin, applied to oilseed rape seeds, reduced wild bee density, solitary bee nesting, and bumblebee colony growth and reproduction under field conditions. Hence, such insecticidal use can pose a substantial risk to wild bees in agricultural landscapes, and the contribution of pesticides to the global decline of wild bees may have been underestimated. The lack of a significant response in honeybee colonies suggests that reported pesticide effects on honeybees cannot always be extrapolated to wild bees.
authors.affiliation: Lund University, Department of Biology, 223 62 Lund, Sweden.
authors.forename: Maj
authors.initials: M
authors.lastname: Rundlöf
authors.affiliation: 1] Lund University, Department of Biology, 223 62 Lund, Sweden [2] Lund University, Centre for Environmental and Climate Research, 223 62 Lund, Sweden.
authors.forename: Georg K S
authors.initials: GK
authors.lastname: Andersson
authors.affiliation: Swedish University of Agricultural Sciences, Department of Ecology, 750 07 Uppsala, Sweden.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Bommarco
authors.affiliation: Swedish University of Agricultural Sciences, Department of Ecology, 750 07 Uppsala, Sweden.
authors.forename: Ingemar
authors.initials: I
authors.lastname: Fries
authors.affiliation: Lund University, Department of Biology, 223 62 Lund, Sweden.
authors.forename: Veronica
authors.initials: V
authors.lastname: Hederström
authors.affiliation: Lund University, Centre for Environmental and Climate Research, 223 62 Lund, Sweden.
authors.forename: Lina
authors.initials: L
authors.lastname: Herbertsson
authors.affiliation: 1] Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment, 750 07 Uppsala, Sweden [2] Swedish University of Agricultural Sciences, Centre for Chemical Pesticides, 750 07 Uppsala, Sweden.
authors.forename: Ove
authors.initials: O
authors.lastname: Jonsson
authors.affiliation: Lund University, Centre for Environmental and Climate Research, 223 62 Lund, Sweden.
authors.forename: Björn K
authors.initials: BK
authors.lastname: Klatt
authors.affiliation: Swedish Board of Agriculture, 551 82 Jönköping, Sweden.
authors.forename: Thorsten R
authors.initials: TR
authors.lastname: Pedersen
authors.affiliation: Lund University, Department of Biology, 223 62 Lund, Sweden.
authors.forename: Johanna
authors.initials: J
authors.lastname: Yourstone
authors.affiliation: 1] Lund University, Department of Biology, 223 62 Lund, Sweden [2] Lund University, Centre for Environmental and Climate Research, 223 62 Lund, Sweden.
authors.forename: Henrik G
authors.initials: HG
authors.lastname: Smith
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000502:physiology; D001516:Bees / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology*; D029741:Brassica rapa / Q000737:chemistry; D018556:Crops, Agricultural / Q000737:chemistry; D005260:Female; D006146:Guanidines / Q000009:adverse effects / Q000494:pharmacology / Q000633:toxicity; D007306:Insecticides / Q000009:adverse effects* / Q000494:pharmacology / Q000633:toxicity; D008297:Male; D000073943:Neonicotinoids; D009425:Nesting Behavior / Q000187:drug effects; D009570:Nitriles / Q000009:adverse effects / Q000494:pharmacology / Q000633:toxicity; D057048:Plant Nectar / Q000737:chemistry; D011058:Pollen / Q000737:chemistry; D054817:Pollination; D011156:Population Density; D011722:Pyrethrins / Q000009:adverse effects / Q000494:pharmacology / Q000633:toxicity; D012098:Reproduction / Q000187:drug effects / Q000502:physiology; D012639:Seeds / Q000737:chemistry; D013548:Sweden; D013844:Thiazoles / Q000009:adverse effects / Q000494:pharmacology / Q000633:toxicity
chemical_list: D006146:Guanidines; D007306:Insecticides; D000073943:Neonicotinoids; D009570:Nitriles; D057048:Plant Nectar; D011722:Pyrethrins; D013844:Thiazoles; C480342:clothianidin; C052570:cyfluthrin