Plight of the Bumblebee - Are Commercial Greenhouses to Blame for the Disappearance of Native Pollinators?
chatnoir
excerpt:
The decline of bumblebees has received far less attention, though in
the public imagination their plight has often been conflated with that
of the honeybee. Not only do bumblebees pollinate about 15 percent of
our food crops (valued at $3 billion), they also occupy a critical
role as native pollinators. Plant pollinator interactions can be so
specific and thus the loss of even one species carries with it
potentially severe ecological consequences. As E. O. Wilson writes,
“If the last pollinator species adapted to a plant is erased … the
plant will soon follow.” There are close to 50 bumblebee species in
the United States and Canada that have evolved with various plants and
flowers over the course of millions of years; our knowledge of those
species, however, is incredibly weak.
In recent years, there has been much loose talk about the overall
decline of pollinators, and the causes are manifold: habitat loss,
pesticides, the spread of disease, and, without fail, global warming.
The tendency to make sweeping claims about the demise of all
pollinators has led to a lack of specificity when it comes to why
particular species have declined, or in the case of B. franklini,
disappeared. One of the only news stories to highlight the plight of
bumblebees, published in The Washington Post last August, noted that
“the causes of bumblebee decline are not scientifically defined and
might be a combination of factors.”
A crucial factor, according to Thorp and other scientists, was the
rise of the commercial bumblebee rearing industry in the early 1990s,
largely for greenhouse tomato pollination. Captive bees, they say,
played a key role in spreading disease, which has led to the decline
of several North American species, all of which belong to the same
subgenus. If their theory proves to be correct, the rapid growth of
the greenhouse tomato industry over the last two decades may have
inadvertently wiped out a number of important native pollinators.