Beekeepers have long suspected the role of the
neonicotinoid insecticides in the great upsurge of honey bee colony die-offs
that have continued since 2006. Named Colony Collapse Disorder, the loss of
honey bee colonies has persisted for eight years in spite of efforts by
researchers to identify a cause and by beekeepers to replenish their hive
numbers. According to the Bee Informed Partnership’s recently released report, http://beeinformed.org/2014/05/colony-loss-2013-2014/,
annual losses have averaged an unsustainable level of nearly 30 percent. A
relatively small-scale study by Harvard School of Public Health, http://www.bulletinofinsectology.org/pdfarticles/vol67-2014-125-130lu.pdf,
reveals interesting findings. Honey bee colonies exposed to either of two low
levels of neonicotinoid insecticides, imidacloprid or clothianidin, abandoned
their hives during the winter, defining symptoms of Colony Collapse Disorder.
This report contrasts somewhat from the results of a previous study on the
effect of pesticides that lead to susceptibility to the honey bee gut pathogen,
Nosema ceranae. The larger study,
reported in PLOS ONE, http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0070182#authcontrib,
finds large numbers and high levels of pesticides in honey bee hives. The
researchers found 35 different pesticides in sampled honey bee pollen and high
levels of fungicides.
Until recently, fungicides, chemicals designed to
fight fungal infections, were considered safe for honey bees. Recent studies
are finding fungicides to have an adverse effect on honey bee health, often
making insecticides and miticides more toxic to bees. In the PLOS ONE study,
fungicides were found to lead to Nosema
infection. Needless to say, the search for the cause of Colony Collapse
Disorder has revealed the complexity of the problem. There are many factors
contributing to honey bee health, including nutrition, parasitic mites, pest
insects, viral, fungal, and bacterial diseases, and environmental chemicals.
Studies are finding insecticides, miticides, fungicides, and herbicides in the
bee hives. Combinations of chemicals and breakdown products of chemicals are
often highly toxic to bees. Peace Bee Farm has participated in a number of the
studies. Today, catalpa trees secrete nectar from the flowers and nectaries on
the leaves.
--Richard
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