Browsing by Subject "Turnip rape"

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  • Byholm, Patrik; Mäkeläinen, Sanna; Santangeli, Andrea; Goulson, Dave (2018)
    The evidence of negative impacts of agricultural pesticides on non-target organisms is constantly growing. One of the most widely used group of pesticides are neonicotinoids, used in treatments of various plants, e.g. oilseed crops, corn and apples, to prevent crop damage by agricultural insect pests. Treatment effects have been found to spill over to non-target insects, such as bees, and more recently also to other animal groups, among them passerine birds. Very little is known, however, on the presence of neonicotinoids in other wild species at higher trophic levels. We present results on the presence of neonicotinoid residues in blood samples of a long-distant migratory food-specialist raptor, the European honey buzzard. Further, we investigate the spatial relationship between neonicotinoid residue prevalence in honey buzzards with that of crop fields where neonicotinoids are typically used. A majority of all blood samples contained neonicotinoids, thiacloprid accounting for most of the prevalence. While neonicotinoid residues were detected in both adults and nestlings, the methodological limit of quantification was exceeded only in nestlings. Neonicotinoids were present in all sampled nests. Neonicotinoid presence in honey buzzard nestlings' blood matched spatially with the presence of oilseed plant fields. These are the first observations of neonicotinoids in a diurnal raptor. For better understanding the potential negative sublethal of neonicotinoids in wild vertebrates, new (experimental) studies are needed. (c) 2018 The Authors. Published by Elsevier B.V.
  • Toivonen, Marjaana; Herzon, Irina; Toikkanen, Jenni; Kuussaari, Mikko (2021)
    Uncultivated field margins are important refugia for pollinating insects in agricultural landscapes. However, the spill-over of pollination services from field margins to adjacent crops is poorly understood. This study (i) examined the effects of landscape heterogeneity on pollinator occurrence in permanent field margins and pollinator visitation to adjacent mass-flowering turnip rape (Brassica rapa ssp. oleifera) in boreal agricultural landscapes, and (ii) tested whether pollinator abundance and species richness in field margins predict abundance and species richness of crop visitors. Pollinators visiting the crop were more affected by landscape heterogeneity than pollinators in adjacent margins. Species richness, total abundance, and the abundance of syrphid flies visiting the crop increased with increasing landscape heterogeneity, whereas, in field margins, landscape heterogeneity had little effect on pollinators. In field-dominated homogeneous landscapes, wild pollinators rarely visited the crop even if they occurred in adjacent margins, whereas in heterogeneous landscapes, differences between the two habitats were smaller. Total pollinator abundance and species richness in field margins were poor predictors of pollinator visitation to adjacent crop. However, high abundances of honeybees and bumblebees in margins were related to high numbers of crop visitors from these taxa. Our results suggest that, while uncultivated field margins help pollinators persist in boreal agricultural landscapes, they do not always result in enhanced pollinator visitation to the adjacent crop. More studies quantifying pollination service delivery from semi-natural habitats to crops in different landscape settings will help develop management approaches to support crop pollination.