April 11, 2012
from
TheGuardian Website
Replacing the pollination of
food crops that the UK's bees perform for free would
cost £1.8bn. With hard data now linking pesticides to
bees' rapid decline, there is no excuse for inaction |
Bees ingest
pesticides from crops treated
with systemic insect
nerve agents,
because the chemicals
are present in nectar and pollen.
Photograph: Simon
Croson/BBKA
How valuable are bees?
In the UK, about
£1.8bn a year, according to new research on the cost of
hand-pollinating the many crops bees service for free. If that
sounds a far-fetched scenario, consider two facts.
First, bees are in severe decline. Half the UK's honey bees kept in
managed hives have gone, wild honey bees are close to extinction and
solitary bees are declining in more than half the place they have
been studied.
Second, hand-pollination is already necessary in some places, such
as pear orchards in China, and bees are routinely trucked around the
US to compensate for the loss of their wild cousins.
The new figure comes from scientists at the Reading University and
was released by Friends of the Earth to launch their new campaign,
Bee Cause.
Paul de Zylva, FoE nature campaigner, said:
"Unless we
halt the decline in British bees our farmers will have to rely on
hand-pollination, sending food prices rocketing."
So what's the problem?
The losses of flowery meadows that feed
wild bees is a factor, as are the parasites and diseases that can
kills hives. But a third factor has now moved to the centre of the
debate: pesticides called
neonicotinoids. The insect nerve-agents
are used as seed dressings, which means they end up in every part of
the crop they protect, including pollen and nectar.
Two landmark studies, conducted in field conditions, published in
Science in March
clearly implicated sub-lethal doses of the
pesticides with increases in disappeared bees and crashes in the
number of queens produced by colonies.
Then on 5 April, another study was
released, showing the
pesticides can cause colony collapse disorder
(CCD), the name given to the ghostly hives from which bees have
vanished.
"The data, both ours and others,
right now merits a global ban," said Chensheng Lu, in the
department of environmental health at Harvard University, and
who led the the CCD study.
"I would suggest removing all
neonicotinoids from use globally for a period of five to six
years. If the bee population is going back up during the after
the ban, I think we will have the answer."
Lu told me he was in no doubt about the
result of his work, which tested the effect of a very widely used
neonicotinoid called
imidacloprid, which is registered for use on
over 140 crops in 120 countries.
"Our study clearly demonstrated that
imidacloprid is responsible for causing CCD, and the survival of
the control hives that we set up side-by-side to the
pesticide-treated hives augments this conclusion."
He said the hives were initially
healthy, were placed in a natural foraging environment and that the
doses of the pesticide the bees were exposed to were realistic.
After 12-weeks of dosing, all the bees were alive, but after 23
weeks, 15 of the 16 treated hives had died - but none of the
untreated control hives. Lu said the dead hives were virtually
empty, as is seen with CCD, and in contrast to the impact of
parasites or disease, which leave hives littered with dead bees.
The leader of one of the Science studies, Mickaël Henry, at INRA in
Avignon, France, agreed with Lu that action is urgently needed on
neonicotinoids.
"We now have enough data to say
authorization processes must take into account not only the
lethal effects, but also the effects of non-lethal doses."
In other words, testing whether the
pesticide use kills bees stone dead immediately is no longer good
enough, given the hard evidence now available that sub-lethal doses
cause serious harm.
So what does the UK government have to say? To date, it has agreed
with the neonicotinoid manufacturers that there is no evidence that
the pesticides used at normal levels cause harm.
A statement on Wednesday from an
environment department spokeswoman suggests no change:
"The UK has a robust system for
assessing risks from pesticides. We keep all the science under
review and we will not hesitate to act if we need to."
What more does it need?
The new data
makes it impossible to maintain this position, whatever vested
interests are at stake. It is 50 years since Rachel Carson published
Silent Spring, which documented the devastation wrought by
pesticides in the US.
What better time to act?
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