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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