This appeared here, and I would like to thank Paul for allowing me to publish his work. RK
Activist groups continue to promote scary stories that honeybees are
rapidly disappearing, dying off at “mysteriously high rates,” potentially
affecting one-third of our food crops and causing global food shortages. Time magazine says readers need to contemplate
“a world without bees,” while other “mainstream media” articles have sported
similar headlines.
The Pesticide Action Network and NRDC are leading campaigns that claim insecticides,
especially
neonicotinoids, are at least “one of the key factors,” if not the principle or
sole reason for bee die-offs.
Thankfully, the facts tell a different story – two stories, actually.
First, most bee populations and most managed hives are doing fine, despite
periodic mass mortalities that date back over a thousand years. Second, where
significant depopulations have occurred, many suspects have been identified,
but none has yet been proven guilty, although researchers are closing in on
several of them.
Major bee die-offs have been reported as far back as 950, 992 and 1443 AD in Ireland. 1869
brought the first recorded case of what we now call “colony collapse disorder,”
in which hives full of honey are suddenly abandoned by their bees. More cases
of CCD or “disappearing disease” have been reported in recent decades, and a
study by bee researchers Robyn Underwood and Dennis vanEngelsdorp chronicles
more than 25 significant bee die-offs
between 1868 and 2003. However, contrary to activist campaigns and various news
stories, both wild and managed bee populations are stable or growing worldwide.
Beekeeper-managed honeybees, of course, merit the most attention, since
they pollinate many important food crops, including almonds, fruits and
vegetables. (Wheat, rice and corn, on the other hand, do not depend at all on
animal pollination.) The number of managed honeybee hives has increased some
45% globally since 1961, Marcelo Aizen and Lawrence Harder reported in Current Biology
– even
though pesticide overuse has decimated China’s bee populations.
Even in Western Europe, bee populations are
gradually but steadily increasing. The trends are similar in other regions
around the world, and much of the decline in overall European bee populations is
due to a massive drop in managed honeybee hives in Eastern Europe, after subsidies ended
with the collapse of the Soviet Union. In fact, since neonicotinoid pesticides
began enjoying widespread use in the 1990s, overall bee declines appear to be
leveling off or have even diminished.
Nevertheless, in response to pressure campaigns, the EU banned neonics – an
action that could well make matters worse, as farmers will be forced to use
older, less effective, more bee-lethal insecticides like pyrethroids. Now
environmentalists want a similar ban imposed by the EPA in the United States.
That’s a terrible idea. The fact is, bee populations tend to fluctuate,
especially by region, and “it’s normal for a beekeeper to lose part of his hive
over the winter months,” notes University of Montana bee scientist Dr. Jerry
Bromenshenk. Of course, beekeepers want to minimize such losses, to avoid
having to replace too many bees or hives before the next pollination season
begins. It’s also true that the United States did experience a 31% loss in
managed bee colonies during the 2012-2013 winter season, according to the US Agriculture Department.
Major losses in beehives year after year make it hard for beekeepers to
turn a profit, and many have left the industry. “We can replace the bees, but
we can’t replace beekeepers with 40 years of experience,” says Tim Tucker, vice
president of the American Beekeeping Federation. But all these are different
issues from whether bees are dying off in unprecedented numbers, and what is
causing the losses.
Moreover, even 30% losses do not mean bees are on the verge of extinction.
In fact, “the number of managed honeybee colonies in the United States has
remained stable over the past 15 years, at about 1.5 million” – with 20,000 to
30,000 bees per hive – says Bryan Walsh, author of the Time article.
That’s far fewer than the 5.8 million managed US hives in 1946. But this
largely reflects competition from cheap imported honey from China and South
America and “the general rural depopulation of the US over the past
half-century,” Walsh notes. Extensive truck transport of managed hives, across
many states and regions, to increasingly larger orchards and farms, also played
a role in reducing managed hive numbers over these decades.
CCD cases began spiking in the USA in 2006, and beekeepers reported losing
30-90% of the bees in many hives. Thankfully, incidents of CCD are declining,
and the mysterious phenomenon was apparently not a major factor over the past
winter. But researchers are anxious to figure out what has been going on.
Both Australia and Canada rely heavily on neonicotinoid pesticides.
However, Australia’s honeybees are doing so well that farmers are exporting
queen bees to start new colonies around the world; Canadian hives are also
thriving. Those facts suggest that these chemicals are not a likely cause. Bees
are also booming in Africa, Asia and
South America.
However, there definitely are areas where mass mortalities have been or
remain a problem. Scientists and beekeepers are trying hard to figure out why
that happens, and how future die-offs can be prevented.
Walsh’s article suggests several probable culprits. Topping his list is the
parasitic Varroa destructor mite
that has
ravaged U.S. bee colonies for three decades. Another is American foulbrood
bacteria that kill developing bees. Other suspects include small hive beetles,
viral diseases, fungal infections, overuse of miticides, failure of beekeepers
to stay on top of colony health, or even the stress of colonies constantly
being moved from state to state. Yet another might be the fact that millions of
acres are planted in monocultures – like corn, with 40% of the crop used for
ethanol, and soybeans, with 12% used for biodiesel – creating what Walsh calls
“deserts” that are devoid of pollen and nectar for bees.
A final suspect is the parasitic phorid fly, which lays eggs in bee
abdomens. As larvae grow inside the bees, literally eating them alive, they
affect the bees’ ability to function and cause them to walk around in circles,
disoriented and with no apparent sense of direction. Biology professor John
Hafernik’s San Francisco University research team said the “zombie-like” bees
leave their hives at night, fly blindly toward light sources, and eventually
die. The fly larvae then emerge from the dead bees.
The team found evidence of the parasitic fly in 77% of the hives they
sampled in the San Francisco Bay area, and in some South Dakota and Central
Valley, California hives. In addition, many of the bees, phorid flies and
larvae contained genetic traces from another parasite, as well as a virus that
causes deformed wings. All these observations have been linked to colony
collapse disorder.
But because this evidence doesn’t fit their anti-insecticide fund-raising appeals,
radical environmentalists have largely ignored it. They have likewise ignored
strong evidence that innovative neonicotinoid pest control products do not harm
bees when they are used properly. Sadly, activist noise has deflected public
and regulator attention away from Varroa mites, phorid flies and other
serious global threats to bees.
The good news is that the decline in CCD occurrence has some researchers
thinking it’s a cyclical malady that is entering a downswing – or that colonies
are developing resistance. The bottom line is that worldwide trends show bees
are flourishing. “A world without bees” is not likely.
So now, as I said in a previous article on this topic, we need to
let science do its job, and not jump to conclusions or short-circuit the
process. We need answers, not scapegoats – or the recurring bee mortality
problem is likely to spread, go untreated or even get worse.
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