Is the focus on insecticides really exaggerated?

In an interview to swissinfo.ch, Simon Bradley reports the opinion of Jean-Daniel Charrière, Head of the Swiss Bee Research Center, Agroscope Liebefeld, that too much focus is given to insecticides, while it has become more difficult to get support to address the Varroa mite issue. I disagree with Charrière’s views and arguments:

Firstly, and it is a serious issue, the figures given for numbers of beekeepers, bee colonies and colony losses are, at the best, rough, but poor and unreliable, estimates. Unfortunately, since 1996 there are no more reliable statistics on beekeeping, i.e. based on scientific grounds, for Switzerland (cf… et si les abeilles nous étaient comptées for a history of the destruction of our official statistics). For instance, in canton of Fribourg where I keep my bee colonies, it is compulsory for every beekeeper to hold a detailed register of her/his bee colonies and losses. None of these data are used for statistics. Instead, we have to fill a survey by the end of January, before winter losses can be estimated! In addition, every canton has its own (or no) regulations.

The second point deals with insecticides. If I agree with Charrière on the diagnostics that the Varroa mite is our major problem, I profoundly disagree with his appreciation that the focus on insecticides is exaggerated. On the contrary, the new molecules, known as neonicotinoids, have much stronger effects than their predecessors, such as DDT. They are active at much lower doses or concentrations and have even stronger effects in combinations, ironically known as “synergetic” effects.

Thirdly, I disagree with the state policy developed for Switzerland (see if the bees took their destiny in hand for a detailed analysis). If Varroa is the major problem and if it is our goal to produce pesticide-free bee-products, the state policy should address consequently these two issues. Instead, the state policy develops and supports agricultural practices where “natural” floreal strips alternate with crops treated with pesticides, both being highly subsidized. How can these nice narrow strips sown with flowers sustain wild and domestic bees, if the bees are intoxicated in the neighbouring crops (where the bees conduct much of their foraging activities)?

Fourth, the argument that we should be more worried for wild bees (because domestic bees have colony compensation mechanisms) does not hold. Reproductive success should be compared in terms of numbers of surviving offspring, i.e. in the case of domestic honey bees, the number of queen-daughters able to produce new colonies. We have already alarming indications of depressed queen-quality induced by insecticides. In addition, domestic honey bees are an emblematic species whose fates reflect what happens to thousands of cryptic insect species. The rough “car-windscreen” test offers qualitative indications of the massive insect species decline that occurred during the last decades.

Finally, beekeepers have been offering for decades (even centuries) free pollination services to the Swiss agriculture, recently estimated to CHF 350 million worth. Charrière mentions that in a few spots these pollination services could already be impaired (see Bill Harby’s paper “Switzerland’s organic honey myth – and how bees are paying the price“).

In a consequent approach to address the question of the bee colony losses, there is little hope to solve the Varroa problem (identified as the major issue), if bees continue to be intoxicated in crops which depend on bees. Both issues should be considered at the same time or separately. The insecticide issue is easy to handle: either stop using such chemicals in crops visited by bees or remove bees from these areas. The Varroa issue is certainly more complicated. However, there are already several promising projects of selecting domestic honey bees able to live with the Varroa mite, like the local Asian honey bee species live with its parasites in their native area. None of these goals has been identified as a priority in the strategic papers recently published in support of honey bees and for a sustainable agriculture( see if the bees took their destiny in hand).

Franci Saucy

Franci Saucy

Franci Saucy, Docteur ès sciences, biologiste, diplômé des universités de Genève et Neuchâtel, est spécialisé dans le domaine du comportement animal et de l’écologie des populations. Employé à l’Office fédéral de la statistique, Franci Saucy est également apiculteur amateur et passionné, et il contribue par ses recherches et ses écrits à l’approfondissement des connaissances sur les abeilles et à leur vulgarisation dans le monde apicole et le public en général.
Franci Saucy est également élu PS à l’exécutif de la Commune de Marsens, dans le canton de Fribourg
Blog privé: www.bee-api.net

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