Bumblebee study seeks citizen scientist input
Bumblebees are declining worldwide, and a University of Arkansas researcher wants to know how Arkansas' native bumbles are faring.
Amber Tripodi, a Ph.D. student, wants to establish baseline populations so patterns of change can be discerned. The last time county-level data was compiled was 1964.
"For instance, in England they have reported localized extinctions of three species," she said. "There, they have the benefit of extensive long-term records with which to compare current bumblebee numbers against through decades of records kept by hobby naturalists and extensive surveys of insects."
"Here in the U.S., we lack those older datasets about past bumblebee abundance," Tripodi said. "Without a proper baseline, which we lack for most of our native bumblebees, it is difficult to tell how they are faring."
Of the 45 species native to the U.S., five seem to be declining: Franklin's bumblebee (Bombus franklini), the rusty-patched bumblebee (Bombus affinis), the western bumblebee, (Bombus occidentalis), the yellowbanded bumblebee, (Bombus terricola), and the American bumblebee (Bombus pensylvanicus).
In 2005 and 2006, the Arkansas Natural Heritage Commission used citizen observations to conduct surveys across the state, "and these hard-working volunteers gave us our first indication that this bumblebee might be in trouble here," she said.
In addition to being adorable, bumblebees serve a unique role in our environment due to their buzz-pollination technique.
"When bumble bees are foraging on certain flowers, you can hear high-pitched buzzes that sound different than ones they make while flying. This sound is actually what releases the pollen." she said. "This is a special pollination behavior in which a bee grabs the flower's anthers and creates a sound by contracting the muscles in her thorax. This vibration is transmitted to the anther, which ejects the pollen and covers the bee."
While most of the pollen will go back to the colony to feed bee larvae, on the way, the bee will stop at dozens of other flowers, fertilizing as she goes.
Plants whose pollen is contained in tube-like structures, instead being of exposed at the end of a filament, depend on bumbles.
"Two of my very favorite fruits, tomatoes and blueberries, have poricidal anthers, and bumble bees are among the best pollinators they have," Tripodi said. "Many people don't realize the role that native bees play in crop pollination, but honeybees just aren't as good at pollinating such specialized flowers."
To accomplish her research goals, Tripodi is looking for help from citizen scientists.
"What we are looking to do is create a more complete picture of the distribution of bumblebees in the state using a limited amount of collecting from as many areas as we can access," Tripodi said. "With collected specimens, species identifications can be verified, and their genetic makeup can be added to our analyses of bumblebee population health.
"Our citizen science survey is a simple and fun way that people can help," she said. "What we are asking is that volunteers collect up to 10 bees a year from their area. We have collecting kits that contain instructions, bee vials, an Arkansas bumble bee identification card and a self-addressed stamped envelope to in which to return the bees."
She is currently working with honey beekeepers and Master Gardeners, who have sent samples. Thanks to their efforts, "we've already added 46 new county-level bumblebee records and have a least a little data on all but 25 counties," Tripodi said. "The more volunteers we get, the clearer a picture we can make of bumblebees in the state."
She's quick to credit her major adviser, Allen Szalanski, professor of entomology at the University of Arkansas, who specializes in insect genetics, a key component of Tripodi's study. "Without his help, I wouldn't have a chance."
Tripodi also credits Jon Zawislak, Extension apiarist with the University of Arkansas Division of Agriculture, for his work in discussing the plight of native bees and encouraging the involvement of the Master Gardeners, a program of the Cooperative Extension Service.
Tripodi expects the research to take two summers, but if there is enough participation, the data updated for the whole state by the end of the year.
For more information on this study, visit http://comp.uark.edu/~aszalan/Apis/Bumble_Bee_Research.html.
To learn more about bumble bees, visit http://comp.uark.edu/~aszalan/Apis/Native_Pollinator_Outreach.html.
For more information on insects and horticulture, contact your county Extension office or visit www.uaex.edu.