Pesticides and honey bee toxicity – USA

[Jon]

I found this review which has a load of background information on the relationship between pesticides and bees. It covers all classes of pesticides including the ones used by beekeepers to control varroa.

Pesticides and honey bee toxicity – USA
Reed M. JOHNSON1, Marion D. ELLIS, Christopher A. MULLIN, Maryann FRAZIER (http://entomology.unl.edu/faculty/ellispubs/Pesticides.pdf)


Abstract – Until 1985 discussions of pesticides and honey bee toxicity in the USA were focused on pesticides
applied to crops and the unintentional exposure of foraging bees to them. The recent introduction
of arthropod pests of honey bees, Acarapis woodi (1984), Varroa destructor (1987), and Aethina tumida
(1997), to the USA have resulted in the intentional introduction of pesticides into beehives to suppress
these pests. Both the unintentional and the intentional exposure of honey bees to pesticides have resulted
in residues in hive products, especially beeswax. This review examines pesticides applied to crops, pesticides
used in apiculture and pesticide residues in hive products. We discuss the role that pesticides and their
residues in hive products may play in colony collapse disorder and other colony problems. Although no
single pesticide has been shown to cause colony collapse disorder, the additive and synergistic effects of
multiple pesticide exposures may contribute to declining honey bee health.

[Neils]

I'm confused, where's the bold and aren't you supposed to tell us what to think about it?

[Jon]

I assume the people who read the forum are intelligent enough to read it and reach their own conclusions based on available evidence.

I think it is a good review which flags up most of the areas of concern re. appropriate tests, the monitoring process, and possible synergistic interactions between different products. Neonicotinoid pesticides do not get a clean bill of health but others are clearly worse. Let's face it, pesticides are not good for honeybees but we have to push for the least worst option. Beekeeper applied miticides are a big part of the mix as well.

[Neils]

I'd be a liar if I said that I'd read it all, I have done the introduction and the conclusion so far, I won't say more until I've read the rest, but my backlog is growing, seemingly by the hour!

[Bumble]

It's good to read something that tries to tie all the various separate research together. It doesn't happen often enough.

I've just skimmed it, but this sentence caught my eye Repeated treatment of colonies with oxalic acid can result in higher queen mortality and a reduction in the amount of sealed brood. It ties in with what, according to my notes, John Hamer says. That each OA treatment shortens a bees life, the impact isn't as noticeable with workers but can have an effect on overwintering.

I did read something, somewhere, and it's probably deep in my bookmarks, that suggested that the US practice of migratory beekeeping on vast monocultures means bees are less healthy because they're unable to access a full range of nutrients, and so less able to deal with problems than UK bees, which are unlikely to have to rely on a single food source. Makes sense to me.

[The Drone Ranger]

I think where there is year round foraging pesticide problems might be worse than here in UK
The flying bees will last 3 or 4 weeks anyway so if chemicals knock them down early thats bad but not terminal
The long break in breeding probably works in favour of the bees even if some traces of chemical are found in the hive