Tessa Everett shows off one of the bumble bees found during field surveys near Mt. Ashland, Oregon. The bee was released unharmed.
Photo by Elizabeth Materna / USFWS
By Elizabeth Materna
Elizabeth Materna is a Public Affairs Officer with the U.S. Fish and Wildlife Service’s Oregon field office.
To many, the sound of a buzzing bee typically elicits
a flight response of their own in an effort to avoid any chance of a sting. But
in mid-July, many folks braved their fears and came together in pursuit of
buzzing bumble bees.
I joined a team looking for two rare species - the
western bumble bee (Bombus occidentalis)
and the Franklin’s bumble bee (Bombus
franklini) in southern Oregon.
The bumble bee blitz was a field trip organized by
the U.S. Fish and Wildlife Service to conduct intensive surveys for these two
rare bumble bees, both of which the Service has been petitioned to list under
the Endangered Species Act. The western bumble bee is widely distributed across
the western United States but has been declining in recent years. The Franklin’s
bumble bee is found only in southwest Oregon and northern California, but it has
not been seen since 2006.
Bees are an integral part of our ecosystem because
they are key pollinators for both crops and wild plants.
One of two western bumble bees found on Mt. Ashland. It was released unharmed after documentation. Photo by Elizabeth Materna / USFWS
There are more than 3,000 bee species in the United States, and almost all are native to North America. Of these, about 40 species belong to the genus Bombus, which are more commonly known as bumble bees. Bumble bees have pollen baskets on their hind legs and are social bees that live and work in colonies headed by a single queen.
Many bee species are
declining at an alarming rate. Although causes are not fully understood, some
theories are loss or fragmented habitat, pesticide use, competition with nonnative honey
bees, low genetic diversity and/or the introduction of nonnative
microorganism that can cause disease.
The goal of the blitz was to comb the meadows around
Mt. Ashland to observe as many bumble bees as possible with the hopes of
finding these two species. Many species were captured and identified – and
released unharmed.
Staff and volunteers examine and document a bumble bee captured during an annual survey on Mt. Ashland. Thebee was released unharmed.
Photo by Elizabeth Materna / USFWS
Numerous volunteers joined biologists from
a variety of federal agencies to conduct the surveys. Those of us that
traveled from the Service’s Oregon Fish and Wildlife Office in Portland camped in tents
along Emigrant Lake, just outside Ashland. Our day started around 7 a.m. with an
adequate dose of caffeine and a quick breakfast before getting surveys underway
around 8:30 a.m.
There’s an interesting bee fact that explains why surveys
for bumble bees can start earlier than searches for other insects. Many insects depend on
the warmth of the sun to raise their body temperature before they are warm
enough to fly (think butterflies and dragonflies). Bumble bees, however, are
able to vibrate and shiver the muscles under their wings, which creates
internal heat that allows them to fly in colder temperatures.
Learn more about bumble bees: http://bit.ly/2aWWa74
Dr. Robbin Thorpe, emeritus professor in the
Department of Entomology and Nematology at the University of California-Davis, is
an expert in the field of bumble bees and was on hand to assist with field
survey techniques and species identification.
“Finding
rare bumble bees at flowers, depends greatly on the search effort, and we had
about 12 participants searching about 10 hours at Mt. Ashland and 17 people searching for six hours at the
Cascade-Siskiyou National Monument,” Thorpe said. “Diverse
bumble bees were found throughout the searches, but only two of the western bumble
bees were seen at Mt. Ashland. This demonstrates the current rarity of this bee,
which was common in the area in 1998 but not seen between 2002-2008. Very
low numbers have been seen each year since 2008, indicating signs of its
recovery. Unfortunately, we can’t say the same for the Franklin’s bumble bee
as the last individual was seen in 2006.”
Biologists compare a bumble bee’s marking to a chart to determine the species. Photo by Elizabeth Materna / USFWS
Eleven species of
bumble bees were recorded during the surveys. Biologists were encouraged with
the diversity because it’s very important to pollination and reproduction in plant
communities. Jeffrey Dillon, Endangered Species Division Manager for the
Service’s Oregon Fish and Wildlife Office and one of the leaders of the
expedition, found one of only two western bumble bees of the trip.
“Through a
collaborative effort between staff from the Service, Bureau of Land Management,
National Park Service, Forest Service, Natural Resources Conservation Service,
and multiple public volunteers, we were able to confirm that the western bumble
bee still occurs on Mt. Ashland,” said Dillon. “This is great news since
it has been more than five years since the western bumble bee was last seen on
Mt. Ashland.”
While Tessa Everett,
5-year-old daughter of a Service biologist who was volunteering, enjoyed the search for bees, she left partially disappointed. “I wish we found a Franklin’s.”
The team will look again next year. I hope to again be among the team because
I learned so much about our native Oregon bumble bees and their habitats.
Information from the surveys will be used in the
Service’s upcoming status review of both bee species
And in case you’re
wondering, only two minor stings were reported.