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Re: Bees and assorted pollinators
GML wrote:
>
> There has been a lot of news about the demise of wild bees and the
> decimation of domestic hives. Some say that there is no real problem,
> merely a temporary "shortage" and that this is all a political
> smokescreen by the beekepers association because Uncle Sugar is cutting
> funding everywhere. Others say that "we" are in big trouble and that a
> minimum of 200 species of plants, shrubs and trees will be dying or
> extinct within two years.
> I'm strictly an amateur, not even a farmer. Could someone with
> credentials cut through the B.S. and tell me what is going on? I
> apologize if this is "old news".
==================
The decline of American / European honeybees is not old news.
I agree w/ "Pollinator" that pesticide application is by far a larger
over-all threat, but the mite infestation going right now is a very
serious short-term threat. The only saving grace for the U.S. is that
once the mite infestation blows over on this continent, we will one day
be able to purchase new bees & restock from the rest of the world ... but
it looks like it will be strictly at the expense of beekeepers.
Your assessment of Uncle Sugar is pretty much on the mark ... there is too
much if that attitude in D.C. that refuses to acknowledge we are facing very
serious environmental problems that have never existed before, but since
they don't have experience (or scientific edjukashun), obviously there is
no need to fix anything ... it will just continue to run "the way it always
has, back in the good old days."
Anyway, here's a news article off the 'Net today I think all beekeepers
should be aware of :
===================================
For bees, Canada is a land of milk and honey compared to U.S.
Copyright (c) 1996 Nando.net, Copyright (c) 1996 Toronto Globe and Mail
(Jul 20, 1996 00:00 a.m. EDT) -- It's been a terrible year for honeybees
in the United States, with cold and disease wiping out more than 80
percent of hives in some northeastern states, but Canada seems to be the
bee's version of a peaceable kingdom.
Even with winter conditions in many parts of the country similar to those
in the United States, hive deaths in Canada are estimated by Gard Otis, a
professor of apiculture at the University of Guelph, to be no more than
one-third of those south of the border -- a bad year in Canada but not as
bad as it might have been.
There are three reasons for Canada's relatively bee-healthy status. The
first is a ban on the import of honeybees from the United States, which
began 10 years ago when outbreaks of the European tracheal mite and then
the varroa mite were first identified.
The tracheal mite takes up residence in the bees' breathing tubes, sucks
up fluids and in so doing restricts oxygen intake. Affected bees are
particularly susceptible to early death during the winter when they try
to increase their metabolic rate in order to heat their hives.
The varroa mites colonize bee larvae and later older bees. Viruses the mites
carry produce birth defects -- for example, no wings or legs -- in the larvae.
Left untreated, the mites can kill a hive in about a year.
The Canadian quarantine means that while most bees in the United States are
infected, Otis estimated that fewer than half of Canadian hives are
afflicted with the deadly mites.
Before the ban there was free movement across the border by beekeepers
bringing hives in to pollinate crops, as well as a regular trade in queen
bees raised in the U.S. South. Although the ban has slowed the mite infection
rate, wild bees have spread the parasites into Canada.
A second reason Canadian bees fared better has to do with mite treatments
available in Canada that can't be used in the United States. In particular,
formic acid, the substance that gives a crushed ant its peculiarly sharp smell,
can be used in Canadian hives. Research has shown that when it is imbedded
into a strip and put in a hive, it will kill mites but not bees.
Douglas McRory, the Ontario Ministry of Agriculture's provincial apiarist, said
Canadian research indicates that formic acid can reduce mite infestations by 95
percent, bringing mite populations to levels low enough that they don't have a
significant effect on honey production.
"If we don't treat the bees, we won't have bees," McRory said.
One stumbling block Canadian beekeepers have surmounted is that formic acid in
too high a concentration acts as an alarm pheromone. Agitated bees respond by
mobbing and killing their queens. However, in lower dosages, formic acid kills
only mites.
Despite formic acid's effectiveness, and even though it's a natural substance
found at low levels in honey, the treatment hasn't passed U.S. regulatory muster.
"It's really something for us to be ahead of the Americans," McRory said.
There are mite-killing pesticides on the U.S. market, but there's some
indication that the mites are developing a resistance to them. Early evidence
suggests resistance will not be a problem with formic acid because above a
certain dose it kills all mites.
The final piece in the relatively rosy Canadian part of the puzzle is the
breeding of mite-resistant bees. From bees originally imported from Buckfast
Abbey in England, Medhat Nasr and his associates at the Ontario Beekeepers
Association have bred a strain that combines resistance to the tracheal mite
with an ability to tolerate Canadian winters.
Recent studies suggest that no mites, or only a few, develop in colonies of
the Buckfast Ontario bees.
The bee's resistance is related to the mite's life cycle. It infects bees in
the first five days of their lives, using smell cues to identify potential targets.
"What we have developed is bees that, while they are still young, smell like
an older bee," Nasr said.
A field trial that pitted 32 Buckfast Ontario hives against eight unprotected
hives showed that mites killed only one of the Buckfast hives compared with six
of the others.
The specially bred bees are being sold in parts of Ontario. A breeding program is
also under way at the University of Guelph in another effort to come up with a
bee resistant to the varroa mite.
One promising line of research is an attempt to breed bees for hygienic behavior --
bees that recognize when larvae have been infected and in response take them out of
the hive and destroy them.
Combining both mite-resistant genetic characteristics in a single bee "would be the
Holy Grail," McRory said.
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