Bijensterfte, oorzaken en gevolgen

Scientists in France have discovered that honeybees are at a higher risk of dying from infection by Nosema ceranae (N. ceranae) when they are exposed to low doses of insecticides. The results, presented in the journal PLoS ONE, support the theory that combining more N. ceranae with a high pesticide content in beehives could contribute to colony depopulation.

On 24 Jan 2011, The National Union of French Beekeeping (UNAF) announced victory at the Council of State for France, against authorization of the pesticide CRUISER® (active substance: thiamethoxam). UNAF requested the cancellation of three annual decisions to allow CRUISER 350, and the condemnation of the Ministry of Agriculture, at a Special Public Hearing of the Council of State of France.

Marie-Pierre Chauzat, Anne-Claire Martel, Nicolas Cougoule, Philippe Porta, Julie Lachaize, Sarah Zeggane, Michel Aubert, Patrice Carpentier And Jean-Paul Faucon, Environ. Toxicol. Chem. 30, pre-published online.

Abstract — The frequency of occurrence and relative concentration of 44 pesticides in apicultural (Apis mellifera) matrices collected from five French locations (24 apiaries) were assessed from 2002 to 2005. The number and nature of the pesticides investigated varied with the matrices examined—living honeybees, pollen loads, honey, and beeswax. Pollen loads and beeswax had the highest frequency of pesticide occurrence among the apiary matrices examined in the present study, whereas honey samples had the lowest. The imidacloprid group and the fipronil group were detected in sufficient amounts in all matrices to allow statistical comparisons. Some seasonal variation was shown when residues were identified in pollen loads.Given the results (highest frequency of presence) and practical aspects (easy to collect; matrix with no turnover, unlike with bees that are naturally renewed), pollen loads were the best matrix for assessing the presence of pesticide residues in the environment in our given conditions.

[Maxim and Van der Sluijs 2010, Environmental Research Letters]

French researchers estimate that 73% of the increased colony collapse in 1994-2004 in areas of extensive agriculture in France has been caused by imidacloprid.

In het Juni 2009 nummer van het Franse INRA magazine (L'Institut National de la Recherche Agronomique) staat een artikel "Le déclin des abeilles, un casse-tête pour la reche; dossier central". Zie:
www.inra.fr/content/download/16788/277180/version/2/file/inra-magazine-9.pdf.