I attended a presentation by someone from SFU on this topic several years 
ago. I am assuming it was Lora Morandin and have pasted the abstact below.
 
I cannot quote Lora given the time that has passed since I heard her 
presentation but ..... I remember her research seemed to suggest that an 
organic farmer could make more money by leaving an uncultivated area in 
the centre of his crop. ( I believe she suggested 160 acres uncultivated 
for 480 acres cultivated).  This uncultivated parcel of land, free of 
pesticides and growing a mixture of native plants, would act as a nursery 
for wild pollinators. The theory being that the increase in wild 
pollinators would act to increase yields in the surrounding crops, hence 
profits.

People seem to interpret this research in two different ways. One view is 
that we can best produce food by nuking a crop with pesticides to kill the 
weeds (and local pollinators), then bring in our nice healthy honey bees 
to do the pollination.
 
Or we can try and limit pesticide use and encourage the growth of wild 
pollinators to help with the job.

The 64 million dollar question seems to be what system is safe and 
sustainable? I expect further research will present some compromise 
solutions. A food production system that kills most wild insects may not 
be somewhere that honeybees can thrive in the long term.
 
The only concern amongst many beekeepers in this debate seems to be how 
much money they can make in their short lives. I think there are many 
other factors to consider, not that I don't like money.

Ted
 
  


Value Language contributor.author Morandin, Lora en date.accessioned 2006-
03-17 - date.available 2006-03-17 - date.issued 2005 en identifier.uri 
http://hdl.handle.net/1892/2386 - description Thesis (Ph.D.) - Biological 
Sciences Department - Simon Fraser University en description.abstract 
Research in agriculture often focuses on development of new technologies 
rather than on potential environmental impacts. Pollinators, primarily 
bees, are essential to agriculture, providing significant yield benefit in 
over 66% of crop species. Currently, dramatic losses of managed honey bee 
pollinators in North America along with suspected world-wide losses of 
wild pollinators are focusing research attention on an impending but still 
poorly documented pollination crisis. Essential questions include: How 
important are wild bees to crop production? Are current agricultural 
practices harming pollinator populations? Can agricultural methods be 
modified in ways that promote pollinators and food production? In this 
thesis I examine the interaction between modern agriculture and wild bees 
through 1) laboratory experiments on effects of new genetically modified 
(GM), systemic, and bio-pest control products on bumble bee (Bombus spp.) 
health and foraging ability, and 2) field experiments on the impacts of 
agricultural landscapes on wild bee abundance, diversity, and pollination 
efficacy. I developed a new method of assessing bee foraging after 
exposure to pesticides that is a useful and sensitive test for sub-lethal 
impacts on pollinators. The GM pesticidal proteins Bt Cry1 Ac and 
chitinase did not negatively affect bumble bee colony or individual health 
or foraging ability. However, the pesticide imidacloprid in the new 
chloronicotinoid family of pesticides impaired bee foraging when bees were 
exposed to elevated doses during larval development. The new biopesticide 
spinosad, which is widely marketed and approved as an organic insecticide, 
rapidly killed bumble bee colonies at elevated doses and impaired foraging 
ability at realistic exposure rates. In field studies, herbicide-tolerant 
genetically modified canola agroecosystems had fewer wild bees than 
organic fields, and there were an intermediate number of bees in 
conventional fields. Low bee abundance in GM fields and to a lesser 
extent, conventional fields was associated with low seed set and reduced 
yields. Weed cover in fields and amount of uncultivated land around fields 
were positively related to bee abundance in fields. We determined that 
crop landscapes with uncultivated areas could have greater yield than 
homogenously tilled landscapes. These data can be used to design 
agroecosystems that benefit both conservation and crop production.  
 Copyright remains with the author en title Wild bees and agroecosystems

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