>>Another point to remember is despite the fact the bees coming out of almonds look great they did last year before the crash.

What do you think about this:  the bees that crashed subsequently were raised on pollen collected in the almonds or after the almonds.  

If that pollen was not healthful (ie. contaminated with agricultural chems), the post-almonds generations of bees had inferior health (immune response, neurological development for orientation, shorter life span or whatever) and easily succumbed to pathogens, for instance, that they normally have no problem coping with.

I think as soon as the unhealthful pollen is consumed or removed by the bees, the colonies recover.  It might be educational to rid CCD-collapsed colonies of the stored pollen and install new packages in the same equipment in areas away from agricultural fields and see how they fare.

I am going to cite an experience from last season that may be related.  Late in the summer another beekeeper and I move hives east for the goldenrod/aster flow.  The bees come back to suburbia in late October to extract and overwinter for the spring/summer flows in suburbia.

I've always associated the markedly more defensive behavior of my bees in the fall with the late season (bees have to defend more to ensure survival).  My explanation for the mellower disposition returning in May was the new, strong nectar flows.

Last year, however, I left some extra hives behind in the homeyard.  They became my control.  When the goldenrod hives came back I noticed how they were so much more defensive compared to the homeyard-bound hives.  I'd say the difference was easily 50-75%.  All of these hives had young queens from the same mother queen.

The goldenrod fields we go to are surrounded by farms - vegetable, potato, sweet corn, sod etc. - and are within 1/4 mile of where the hives are put.  I know sod farms especially apply frequent sprays for grubs and the other crops are sprayed as well.  

I think the pesticides are getting into my goldenrod hives with the autumn pollen - I don't know if the bees work the farm fields themselves or if the pesticide fumes carry to the goldenrod fields.  This is the only possible explanation I can come up for my goldenrod hives having a very short fuse.

Another local beekeeper who used to keep an apiary in the farms by our goldenrod fields for pollination contracts has for years complained that his hive over there overwinter poorly and never built up properly in the spring compared to his suburban locations.  He has just moved his hives out of the farms and is not going back.

Other beekeepers who do agricultural pollination around here say that when the hives come back home they find more cases of foulbrood.  The thought has been that there are more AFB spores on the farms ['because bees have been placed in the same locations for years'].  

This has been a plausible explanation but now I wonder if those bees, because of the exposure, are just plain weaker and their larvae succumb easier to AFB spores or the nurse bees are less hygienic...

I am not saying this is definitive by any measure but something definitively seems to 'stink' on commercial farms around here. 

Waldemar 

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