Honey bee brood ring-test: method for testing pesticide toxicity on honeybee brood in laboratory conditions

contribution to session IV Test methodology The Experimental unit of entomology (INRA, France) developed a new in vitro method to assess effects of pesticides on honey bee larvae. The method consists in rearing bee larvae in plastic cells. The larvae are fed with diet containing 50% of fresh royal jelly and 50% of an aqueous sugar and yeast extract solution, and reared in an incubator at 35 °C and 96% relative humidity. According to that method, 9 tests (7 in 2008 and 2 in 2005) were carried out in 7 laboratories and different countries. The objective of these trials was to assess the LD50 for dimethoate 48 hours after an acute exposure. The LD50 values ranged from 1.5 μg a.i./larva to 8.8 μg a.i./larva, with 2 tests with particularly high values (5.0 and 8.8 μg a.i./larva). In 7 tests, these values ranged from 1.5 μg a.i./larva to 3.1 μg a.i./larva. Such variability may be due to the colony origin, the season and larva heterogeneity at grafting. Solutions are proposed to improve the method through the continuation of the ring test. Keywords: Apis mellifera, brood, in vitro test, dimethoat

CSI pollen: diversity of honey bee collected pollen studied by citizen scientists

A diverse supply of pollen is an important factor for honey bee health, but information about the pollen diversity available to colonies at the landscape scale is largely missing. In this COLOSS study, beekeeper citizen scientists sampled and analyzed the diversity of pollen collected by honey bee colonies. As a simple measure of diversity, beekeepers determined the number of colors found in pollen samples that were collected in a coordinated and standardized way. Altogether, 750 beekeepers from 28 different regions from 24 countries participated in the two-year study and collected and analyzed almost 18,000 pollen samples. Pollen samples contained approximately six different colors in total throughout the sampling period, of which four colors were abundant. We ran generalized linear mixed models to test for possible effects of diverse factors such as collection, i.e., whether a minimum amount of pollen was collected or not, and habitat type on the number of colors found in pollen samples. To identify habitat effects on pollen diversity, beekeepers’ descriptions of the surrounding landscape and CORINE land cover classes were investigated in two different models, which both showed that both the total number and the rare number of colors in pollen samples were positively affected by ‘urban’ habitats or ‘artificial surfaces’, respectively. This citizen science study underlines the importance of the habitat for pollen diversity for bees and suggests higher diversity in urban areas

La disette pollinique printanière augmente les pertes de colonies en paysages agricoles

Au cours des cinquante dernières années, les paysages agricoles ont été profondément modifiés en réponse à une intensification des pratiques agricoles. En a résulté une perte d’habitats semi-naturels et une érosion de la biodiversité appauvrissant la disponibilité en ressources florales, l’unique ressource alimentaire des abeilles. Bien qu’un tiers à la moitié des cheptels apicoles – Apis mellifera – soit perdu chaque hiver en Europe et en Amérique du Nord, il n’y a toujours aucune étude démontrant un lien de causalité entre le manque de ressources florales disponibles en saison et les pertes de colonies d’abeilles après l’hivernage. Notre étude récemment publiée dans la revue Journal of Applied Ecology (Requier et al. 2017), vise à combler ce manque.Fil: Requier, Fabrice. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Universidad Nacional de Rio Negro. Sede Andina; Argentina. Institut National de la Recherche Agronomique; FranciaFil: Jean François Odoux. Institut National de la Recherche Agronomique; Franci

Melliferous Potential of Weedy Herbaceous Plants in Crop Fields of Romania from 1949 to 2012

Intensive farming systems have led to reduced food availability for honey bees which could be related to their current decline. A global tool is needed in order to assess the melliferous potential of plant species that could be developed as crops or companion plants in such systems. This review is based upon a survey from an extensive dataset collected in Romania over the last sixty years to record the nectar production of 153 weedy species. While there was considerable variation among these plants, we found that the melliferous potential of such large families as the Brassicaceae was low, that of the Apiaceae, Asteraceae and Fabaceae at an intermediate level, and that of the Lamiaceae and Boraginaceae the highest. High nectariferous potential was found to be an important feature of perennial ruderal species. Within the main flowering season, perennials provided much more nectar than annuals. These results could help to develop new agricultural practices more compatible with honey bee colony survival and honey production, as some of these plant species could provide a solution to enable agriculture and beekeeping to coexist in a sustainable way

Les organisations professionnelles apicoles dans la région de Fès-Meknès au Maroc

Moroccan beekeeping is widely supported by the Government. The Region of Fès-Meknès chose to position beekeeping as a lever for rural development. Through a census with regional authorities then interviews with44 beekeeping groups, our study proposes an approach that is part of a sector diagnosis. The data collected reveal the importance of cooperatives in collective forms of beekeeping production, and the involvement of rural youth and women in decision-making processes. The heterogeneous beekeeping practices reflect an adaptation of traditional methods to modern techniques, but certain practices, in particular bee health, remain empirical. The initial training of people is an asset for the sector structuration and can also allow agood livestock management by breeders. We emphasized the diversity of honeys to highlight the region’sbeekeeping potential through varied and continuousfloral resources allowing hive moving in order to harvest typical honeys in accordance with the available melliferous potential. Little equipped with stainless steel tools, beekeepers remain demanding in terms of honey houses’equipment. The modest production is largely sold at retail and the packaging is still to be improved for an appropriate recognition of the product. Participation of beekeepers in some shows contributes favourably to building a regional identity image.La filière apicole est largement soutenue par l’État au Maroc. La région de Fès-Meknès a choisi de positionner l’apiculture comme un levier de développement rural. À travers un recensement auprès des administrations concernées, puis d’enquêtes auprès de 44 organisations professionnelles apicoles, notre étude propose une approche s’inscrivant dans un diagnostic de filière régionale. Les données recueillies révèlent l’importance des coopératives dans les formes collectives de production apicole et l’implication de jeunes ruraux et de femmes dans les processus de décision. Les techniques apicoles sont hétérogènes,traduisant une adaptation des méthodes traditionnelles aux techniques modernes, mais avec certaines pratiques, notamment sanitaires, qui restent empiriques. La formation initiale des personnes est un atout aussi bien pour la structuration de la filière que du point de vue de la maîtrise du cheptel. Les ressources florales sont variées et continues au niveau de cette grande région, permettant d’imaginer des transhumances pour récolter des miels typiques dans le respect des potentiels disponibles. Peu équipés en matériel inox, les apiculteurs restent demandeurs en termes d’équipements de miellerie. La production modeste est largement écoulée au détail et le conditionnement reste à améliorer pour une bonne reconnaissance du produit. La participation des apiculteurs aux salons régionaux contribue favorablement à une image identitaire qui devra être cultivée

Abeilles et composante ligneuse

International audienceEspèce mutualiste [1] et polylectique [2], l'abeille domestique est impliquée dans le processus de pollinisation de nombreuses plantes à fleurs sauvages et cultivées. En contrepartie, elle profite de la floraison de ces plantes pour l'acquisition de ressources polliniques et nectarifères [3]. Elle interagit avec une multitude de composantes paysagères et d'espèces floristiques [4]. Pourtant, on constate depuis une vingtaine d'années une forte diminution des populations d'abeilles domestiques et sauvages [5]. Celle-ci reste encore inexpliquée sur bien des aspects

Neonicotinoid-induced mortality risk for bees foraging on oilseed rape nectar persists despite EU moratorium

International audienceThe implication of neonicotinoids in bee declines led in 2013 to an EU moratorium on three neonicotinoids in bee-attractive crops. However, neonicotinoids are frequently detected in wild flowers or untreated crops suggesting that neonicotinoids applied to cereals can spread into the environment and harm bees. Therefore, we quantified neonicotinoid residues in nectar from winter-sown oilseed rape in western France collected within the five years under the EU moratorium. We detected all three restricted neonicotinoids. Imidacloprid was detected in all years with no clear declining trend but a strong inter- and intra-annual variation and maximum concentrations exceeding reported concentrations in treated crops. No relation to non-organic winter-sown cereals was identified even though these were the only crops treated with imidacloprid, but residue levels depended on soil type and increased with rainfall. Simulating acute and chronic mortality suggests a considerable risk for nectar foraging bees. We conclude that persistent imidacloprid soil residues diffuse on a large-scale in the environment and substantially contaminate a major mass-flowering crop. Despite the limitations of case-studies and risk simulations, our findings provide additional support to the recent extension of the moratorium to a permanent ban in all outdoor crops

The composition of agricultural landscapes influences life history traits of honeybee workers

Honeybee workers play a major role within the colony by taking care of the breeding of larvae until the supply in food of the entire colony, by division of tasks. The age polyethism offers to the worker the capacity to carry out successively the totality of these tasks, following its age. It is known that the worker switches the tasks following a gradient internal-outside the hive during its imago life, the oldest workers making the foraging tasks. However, the available food in agricultural landscape is managed by the entomophilous crop phenology. To insure the food resource income in the colony, the workers have to adapt their life histories according to the available food. The originality of this work concerns the use of the RFID technology (Radio Frequency IDentification), recently adapted to the honeybee. This tool allows to follow continuously income/outcome of the bees during all their lifespan. Emergent workers are tagged with a transponder just before being introduced in the colony. 1640 workers life history were followed in this study, born in various periods of the season, during the bloom of the entomophilous crops versus not. For the first time the results allowed to characterize exactly the bee’s life history by behavioural analysis. This characterization shows that the temporal available food dynamics of the resources in agricultural landscape influences strongly the life history of bees at the individual level

A common pesticide decreases foraging success and survival in honey bees.

International audienceNonlethal exposure of honey bees to thiamethoxam (neonicotinoid systemic pesticide) causes high mortality due to homing failure at levels that could put a colony at risk of collapse. Simulated exposure events on free-ranging foragers labeled with a radio-frequency identification tag suggest that homing is impaired by thiamethoxam intoxication. These experiments offer new insights into the consequences of common neonicotinoid pesticides used worldwide