VANCOUVER,
British Columbia — Around the world, honeybee colonies are dying in
huge numbers: About one-third of hives collapse each year, a pattern
going back a decade. For bees and the plants they pollinate — as well as
for beekeepers, farmers, honey lovers and everyone else who appreciates
this marvelous social insect — this is a catastrophe.
But
in the midst of crisis can come learning. Honeybee collapse has much to
teach us about how humans can avoid a similar fate, brought on by the
increasingly severe environmental perturbations that challenge modern
society.
Honeybee
collapse has been particularly vexing because there is no one cause,
but rather a thousand little cuts. The main elements include the
compounding impact of pesticides applied to fields, as well as
pesticides applied directly into hives to control mites; fungal,
bacterial and viral pests and diseases; nutritional deficiencies caused
by vast acreages of single-crop fields that lack diverse flowering
plants; and, in the United States, commercial beekeeping itself, which
disrupts colonies by moving most bees around the country multiple times
each year to pollinate crops.
The
real issue, though, is not the volume of problems, but the interactions
among them. Here we find a core lesson from the bees that we ignore at
our peril: the concept of synergy, where one plus one equals three, or
four, or more. A typical honeybee colony contains residue from more than
120 pesticides. Alone, each represents a benign dose. But together they
form a toxic soup of chemicals whose interplay can substantially reduce
the effectiveness of bees’ immune systems, making them more susceptible
to diseases.
These
findings provide the most sophisticated data set available for any
species about synergies among pesticides, and between pesticides and
disease. The only human equivalent is research into pharmaceutical
interactions, with many prescription drugs showing harmful or fatal side
effects when used together, particularly in patients who already are
disease-compromised. Pesticides have medical impacts as potent as
pharmaceuticals do, yet we know virtually nothing about their
synergistic impacts on our health, or their interplay with human
diseases.
Observing
the tumultuous demise of honeybees should alert us that our own
well-being might be similarly threatened. The honeybee is a remarkably
resilient species that has thrived for 40 million years, and the
widespread collapse of so many colonies presents a clear message: We
must demand that our regulatory authorities require studies on how
exposure to low dosages of combined chemicals may affect human health
before approving compounds.
Bees
also provide some clues to how we may build a more collaborative
relationship with the services that ecosystems can provide. Beyond
honeybees, there are thousands of wild bee species that could offer some
of the pollination service needed for agriculture. Yet feral bees —
that is, bees not kept by beekeepers — also are threatened by factors
similar to those afflicting honeybees: heavy pesticide use, destruction
of nesting sites by overly intensive agriculture and a lack of diverse
nectar and pollen sources thanks to highly effective weed killers, which
decimate the unmanaged plants that bees depend on for nutrition.
Recently,
my laboratory at Simon Fraser University conducted a study on farms
that produce canola oil that illustrated the profound value of wild
bees. We discovered that crop yields, and thus profits, are maximized if
considerable acreages of cropland are left uncultivated to support wild
pollinators.
A
variety of wild plants means a healthier, more diverse bee population,
which will then move to the planted fields next door in larger and more
active numbers. Indeed, farmers who planted their entire field would
earn about $27,000 in profit per farm, whereas those who left a third
unplanted for bees to nest and forage in would earn $65,000 on a farm of
similar size.
Such
logic goes against conventional wisdom that fields and bees alike can
be uniformly micromanaged. The current challenges faced by managed
honeybees and wild bees remind us that we can manage too much. Excessive
cultivation, chemical use and habitat destruction eventually destroy
the very organisms that could be our partners.
And
this insight goes beyond mere agricultural economics. There is a lesson
in the decline of bees about how to respond to the most fundamental
challenges facing contemporary human societies. We can best meet our own
needs if we maintain a balance with nature — a balance that is as
important to our health and prosperity as it is to the bees.
Mark Winston,
a biologist and the director of the Center for Dialogue at Simon Fraser
University, is the author of the forthcoming book “Bee Time: Lessons
From the Hive.”
Web: forhumanliberation
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