Plight of the bumblebee
Adam Federman
Like bees, the bumble bee has also
been experiencing declines in recent years. A number of factors are
believed to have caused the so-called Colony Collapse Disorder, one of
which could be the rise of the commercial bumblebee rearing industry
since the early 1990s.
Bombus franklini, a North American bumblebee, was last seen on August
9, 2006. Professor Emeritus Robbin Thorp, an entomologist at UC Davis,
was doing survey work on Mt. Ashland in Oregon when he saw a single
worker on a flower, Sulphur eriogonum, near the Pacific Crest Trail. He
had last seen the bee in 2003, roughly in the same area, where it had
once been very common. “August ninth,” Thorp says. “I’ve got that
indelibly emblazoned in my mind.”
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A single worker on a flower |
Keeping tabs
Thorp had been keeping tabs on the species since the late 1960s. In
1998, he began a monitoring project to find out why franklini’s range is
so restricted while other bumblebees’ i.e. its close relative Bombus
occidentalis, are not. While conducting the study, he found that the
populations of both bees began to decline precipitously. Bees, and
particularly the European honeybee, Apis mellifera, have come to
symbolize a deepening ecological crisis in North America. Colony
Collapse Disorder, first reported in 2006, has been described as “an
insect version of AIDS,” ravaging honeybee colonies throughout North
America.
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 US
food crops (valued at US$3 billion), they also occupy a critical role as
native pollinators.
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The causes of bumblebee decline are not scientifically defined.
Google Images |
Plant pollinator interactions can be so specific and thus the loss of
even one species carries with it potentially severe ecological
consequences. 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.
Plight of bumblebees
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.
- Third World Network Features
To be continued tomorrow
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