- Author: Kathy Keatley Garvey
How many different bumble bee species have you seen or photographed this year?
Have you seen the black-tailed bumble bee, Bombus melanopygus? It's the earliest to emerge in this area.
We photographed several B. melanopygus on Jan. 25 near downtown Benicia. Three were foraging on rosemary and one on a rose.
B. melanopygus is native to western North America and found from California to British Columbia and as far east as Idaho, it forages on manzanitas, wild lilacs, wild buckwheats, lupines, penstemons, clovers, and sages, among others.
Our little Bombus posse--Allan Jones, Gary Zamzow and Kim Chacon, all of Yolo County, and yours truly of Solano County--annually compete to find and photograph the first bumble bee of the year. As earlier mentioned, Jones won the 2020 contest--he photographed a B. melanopygus on Jan. 6 in the UC Davis Arboretum and Public Garden. No bumble bees are harmed in this contest. We don't poke 'em, prod 'em or pin 'em. We just take their picture, or rather, we capture their images.
The contest began in 2012 with our mentor, Robbin Thorp (1933-2019), distinguished emeritus professor of entomology, UC Davis Department of Entomology and Nematology. To memorialize him, the contest will now be known as Robbin Thorp Memorial Bumble Bee Contest and will sponsored by the Bohart Museum of Entomology, where the professor spent much of his time.
Thorp, a member of the UC Davis entomology faculty for 30 years (1964-1994), achieved emeritus status in 1994 but continued to engage in research, teaching and public service until a few weeks before his death. In 2014, during his retirement, he co-authored two books, Bumble Bees of North America: An Identification Guide California Bees and Blooms: A Guide for Gardeners and Naturalists. He co-taught The Bee Course from 2002 to 2019. This is an intensive nine-day workshop affiliated with the American Museum of Natural History and held annually at the Southwestern Research Station, Portal, Ariz. It's geared for conservation biologists, pollination ecologists, and other biologists who want to gain greater knowledge of the systematics and biology of bees.
The good professor was always concerned about the declining bumble bees, especially Franklin's bumble bee, found only in a small range in Southern Oregon and Northern California. He was a global authority on bumble bees and sounded the alarm to protect bumble bees, including this one. Lynn Kimsey, director of the Bohart Museum of Entomology and a UC Davis professor, fears it is extinct. No one has seen it since Thorp spotted it in 2006. (See Bug Squad)
Meanwhile, keep an eye out for bumble bees, and do what you can to protect them (plant flowers that they prefer and don't use pesticides). Robbin Thorp would have liked that.




- Author: Kathy Keatley Garvey
Especially when it comes to bumble bee colonies.
Postdoctoral scholar Rosemary Malfi of the Neal Williams lab, University of California, Davis, will speak on “Timing Is Everything: Bumble Bee Colony Performance in Response to Seasonal Variation in Resources” at 4:10 p.m., Wednesday, May 30 in 122 Briggs Hall.
“Wild bee populations are considered to be strongly regulated by the availability of flowering resources on which they rely for food, that is, pollen and nectar, yet we lack robust, experimental data demonstrating the mechanistic connections between the floral resource environment and bee population health," Malfi says. "The temporal distribution of resources, in particular, is an understudied but potentially highly influential aspect of habitat quality affecting bees. Bumble bees (Bombus spp.) are annual, euosocial insect with high conservation value. Because their colonies must grow for several weeks before reproducing the timing of within-season resource abundance and scarcity is especially likely to impact their demographic performance."
At her seminar, Malfi will describe her postdoctoral work here at UC Davis, "in which we investigated the importance of the timing of floral resource abundance for bumble bee (Bombus vosnesenkii) colony success through two large field experiments involving the manipulation of the food environment that colonies experienced. In the first study, we assessed how differences in the resource environment early in colony development affected both individual and colony level traits across the season using radio-frequency technology (RFID) and mark recapture methods. In the second study, we determine whether a pulse of food resources early in development, compared to a pulse delivered later during the 'pre-reproductive' phase, has a greater or similar impact on the peak size and reproduction of bumble bee colonies. We use a null method of exponential colony growth to explore whether resource pulses have persistent effects on colony growth after the pule itself has disappeared. Together these studies demonstrate that resource abundance early in development is critical for the success of bumble bee colonies, and this populations."
A native of Philadelphia, Rosemary received her bachelor of arts degree from Bryn Mawr College, an all-women's liberal arts school in the greater metro area, and worked two years at the Academy of Natural Sciences of Philadelphia as a lab manager for the in-house Patrick Center for Environmental Research.
Mali holds a doctorate in environmental science (ecology) from the University of Virginia in 2015 , studying with major professor T'ai Roulston. She focused her doctoral research on the influence that flower (i.e. food) availability and parasitism have on bumble bee (Bombus spp.) population dynamics, and how risks associated with these factors vary among species within a community. In her work, integrating field observations, parasite analysis, colony manipulations, the use of radio frequency technology, and simulation modeling, she investigated these sources of environmental influence independently and interactively through studies that focus on bumble bee populations and environmental risks present in northern Virginia.
Among the bumble bee parasites Malfi has studied: Nosema bombi, a pathogenic fungus implicated in "the precipitous and rapid decline of several bumble bee species across North America." During her graduate studies, she became especially interested in the interaction between bumble bees and one of their parasitoids, the conopid fly. "Although the basic biology of this interaction has been described," she says, "little is currently known about the ecology of this host-parasitoid relationship, particularly in North America." Malfi discussed her work on the conopid fly at the January 2016 open house of the Bohart Museum of Entomology, UC Davis.
Malfi's postdoctoral position at UC Davis ends in September, and then she will be moving to Massachusetts with her family. She will be working in the lab of Lynn Adler at the University of Massachusetts, Amherst, to carry out research on the influence of diet on bumble bee colony development and health.
Career plans? "For now, my career plans are to continue pursuing research on wild bee population health," she says. "In my next position at UMass Amherst, I'll be focusing on how the diet of bumble bees may mediate the influence of pathogenic parasites on individual- and colony-level performance."


- Author: Kathy Keatley Garvey

Billed as "the first comprehensive guide to North American bumble bees to be published in more than a century," it allows readers, both amateurs and professionals, to identify all 46 bumble bee species found in North America and learn about their ecology, changing geographic distributions, and the endangered and threatened species.
Bumble bees, you know, are among the most recognizable of the world's 20,000 species of bees. The genus, Bombus, has only 250 species. A small number, indeed.


