This study from Spain definitively delinked bee losses from imidacloprid and pesticides in general

In the last decade, an increase in honey bee colony
losses have been reported in several European and
American countries (Gross 2007, 2008), including
Spain, where recent data from many apiarists, indicate
a loss close to 80% of beehives

Spain is the European country with the highest number
of honey bee colonies (2.5 millions in 2009)

Our results demonstrate that the situation in Spain
is similar to that described in countries in other studies
but differs in the lack of imidacloprid residues.

Indeed, it seems that the generalized
honey bee colony loss in recent years is more
likely to be related to other causes such as varroosis
due to V. destructor

In our samples, the prevalence of fipronil was very low, and
imidacloprid (or metabolites) was not detected, suggesting
that those products or other agrotoxics commonly
used in Spain are not directly related with the
generalized reemergent problem of honey bee colony
loss detected since autumn 2004.

Overview of Pesticide Residues in Stored Pollen and Their
Potential Effect on Bee Colony (Apis mellifera) Losses in Spain

the Authors

J. Bernal, E. Garrido-Bailón, M. J. Del Nozal, A. V. González-Porto, R.
Martín-Hernández, J. C. Diego, J. J. Jiménez, J. L. Bernal, and M. Higes

their affiliations

IU CINQUIMA, Analytical Chemistry Group, University of
Valladolid, E-47071 Valladolid, Spain.

Centro Apicola Regional. Bee Pathology Laboratory. Consejeria
de Agricultura, Marchamalo. E-19180 Guadalajara, Spain.
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