- Author: Kathy Keatley Garvey
Yes, after a l-o-n-g, cold, hard winter, bumble bees are emerging.
At least in Solano County.
At 11:20 a.m. today (Wednesday, Jan. 13), we spotted a yellow-faced bumble bee, Bombus vosnesenskii, foraging on oxalis near downtown Benicia.
What a delight! A January bumble bee and the first one we've seen this year.
So, this is a good time to mention the inaugural Robbin Thorp First-Bumble-Bee-of-the-Year Contest, sponsored by the Bohart Museum of Entomology and coordinated by Bohart director Lynn Kimsey, UC Davis professor of entomology.
Just photograph a clearly identifiable bumble bee in the two-county area of Yolo or Solano, and submit it to bmuseum@ucdavis.edu with the time, date and place. The winner receives bragging rights and a special gift from the Bohart Museum. Plans call for a Bohart coffee mug with a bumble bee image.
The contest memorializes native pollinator specialist and Bohart associate Robbin Thorp (1933-2019), UC Davis distinguished emeritus professor of entomology. Professor Thorp, 85, who died June 7, 2019, was a global authority on bumble bees, and always looked forward to seeing the first bumble bee of the year. He launched an impromptu contest several years ago with a small group of bumble bee enthusiasts/photographers (including yours truly) from Yolo and Solano counties. (Note: I am not a contestant.)
Early Bumble Bees
The black-tailed bumble bee, Bombus melanopygus, is usually the first bumble bee to emerge in this area, Thorp used to say. It forages on manzanitas, wild lilacs, wild buckwheats, lupines, penstemons, clovers, and sages, among others. In early January, it's often seen on manzanita blossoms in the UC Davis Arboretum and Public Garden. B. vosnesenskii forages on such early bloomers as oxalis, jade, mustard and wild radish, and then on a variety of plants throughout the year. Both species are natives.
Thorp, a 30-year member of the UC Davis entomology faculty, from 1964-1994, co-authored two books, Bumble Bees of North America: An Identification Guide (Princeton University, 2014) and California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday, 2014). He achieved emeritus status in 1994 but continued to engage in research, teaching and public service until a few weeks before his death.
A tireless advocate of pollinator species protection and conservation, Thorp was known for his expertise, dedication and passion in protecting native pollinators, especially bumble bees, and for his teaching, research and public service. He was an authority on pollination ecology, ecology and systematics of honey bees, bumble bees, vernal pool bees, conservation of bees, native bees and crop pollination, and bees of urban gardens and agricultural landscapes.
Ready to join the hunt for the first bumble bee of the year in Yolo and Solano counties? Camera ready? Walking shoes laced? Go!




- Author: Kathy Keatley Garvey
Benjamin Franklin reportedly said: "Early to bed and early to rise, makes a man healthy, wealthy, and wise."
What about the sleeping patterns of bumble bees?
Bumble bees are definitely early risers--if the weather cooperates. They usually forage earlier than honey bees and also in cooler temperatures.
We spotted this bumble bee, Bombus melanopygus, commonly known as a "black-tailed bumble bee," sleeping on a Spanish lavender blossom April 12 in a Vacaville, Calif. park.
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.
Keep your eye out for this bumble bee, which is the first species we see in this area. It will be the focus of the Robbin Thorp Memorial Bumble Bee Contest, which starts Jan. 1, 2021. The Bohart Museum of Entomology, directed by Lynn Kimsey, UC Davis professor of entomology, will sponsor the contest to see who can find the first one of the year.
Professor Thorp (1933-2019), a member of the UC Davis entomology faculty for 30 years, from 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 and California Bees and Blooms: A Guide for Gardeners and Naturalists. He was among the instructors (2002-2019) of The Bee Course. 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.
For the past several years, several of us bumble bee enthusiasts, encouraged by Professor Thorp, have tried to find the first bumble bee of the year in the two-county area of Yolo and Solano. He always expressed delight when we reported back to him. This year Allan Jones of Davis photographed one on Jan. 6 on a white manzanita in the UC Davis Arboretum and Public Garden (Yolo County) to win the contest. The bumble bee been found as early as Jan. 1 in Benicia (Solano County).
Still, no matter the month, it's a joy to see. This one's for you, Robbin.



- Author: Kathy Keatley Garvey
Macro insect photographer extraordinaire Allan Jones captured an image of a female black-tailed bumble bee, Bombus melanopygus on Monday, Jan. 6 on the UC Davis campus.
- The time: 1:45 p.m.
- The place: On white manzanita, just east of the 0ld Redwood Grove past the Old Davis Road/Arboretum Drive entrance, UC Davis Arboretum and Public Garden
- The temperature: About 56 degrees
"From the looks of her pollen load, she has been out collecting for some time now, so she must have been collecting earlier when it was colder yet," Jones reported. He saw one yesterday (Jan. 5 in Davis) west of El Macero but the bumble bee flew before he could photograph it. "I figured the black-tail ground nests were warmed up enough so they would be out early."
Jones, who worked closely with global bumble bee authority Robbin Thorp (1933-2019), distinguished professor of entomology at UC Davis, explained the warming of the nests:
"One summer while shooting bees soon after dawn at a lavender farm in the foothills, the first flight of bees were the bumble bees. Once it warmed up some, the honey bees showed up. So a few years ago I asked Robbin why on chill winter days I was seeing lots of honey bees, but no bumble bees. (Of course I was eager to win our contest.)
"He explained that bumble bees often nest facing north so that in cold mountainous climates, the warm southern sunshine does not warm their nests and lure them into a sudden drop in temperature or a snow squall that would kill them. Instead they wait for the ground and their nest to warm a bit before they venture out. It was Robbin's reasoning that lead me to believe that yesterday's B. melanopygus sighting in South Davis proved that local nests were warm enough that they would be flying with honey bees in the low '50s. A few years ago, the winner went out and got a shot on a day with very low temperatures as well, but she was on campus where buildings produce some tropical microclimates. This year I decided to get out early."
The Contest
A little bit about the contest: Thorp launched the contest in 2012 with a small group of bumble bee enthusiasts/photographers: Allan Jones and Gary Zamzow of Yolo County, and yours truly of Solano County. Later UC Davis doctoral student Kim Chacon with the Geography Graduate Group (and on track to receive her doctorate in June 2020), joined the group. Chacon, who studies "habitat connectivity issues for bees at a landscape scale" (see her website on Resilient Bee Landscapes), worked closely with Thorp until his death in June 2019. She is a 2018 alumnus of The Bee Course, co-taught by Thorp.
The rules are simple: the first one who photographs the first bumble bee of the year in Yolo or Solano County wins the title! (No reward, just bragging rights)
The Bee
The first bumble bee to emerge in this area is the black-tailed bumble bee, Bombus melanopygus. 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.
Thorp, a member of the UC Davis entomology faculty for 30 years, from 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 and 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 Arboretum
The 100-acre UC Davis Arboretum and Public Garden, spanning the 5300-acre campus, is a landmark on the UC Davis campus--and traces its beginnings to more than 80 years ago. As the website says, it includes "demonstration gardens and scientific collections as well as the Putah Creek Riparian Reserve – a rare stream and grassland ecosystem managed for teaching, research, wildlife and habitat protection."
Go visit the Arboretum--and be sure to look for the bumble bees!


- Author: Kathy Keatley Garvey
It's not a $64,000 question, because there's no reward--just bragging rights.
Game on!
Robbin Thorp (1933-2019), a global authority on bees and a distinguished emeritus professor of entomology at the University of California, Davis, launched the first-bumble-bee-of-the-year contest with a small group of bumble bee enthusiasts/photographers.
Professor Thorp, Allan Jones, Gary Zamzow, all of Yolo County, and yours truly, of Solano County, are founding members. Later UC Davis doctoral student Kim Chacon with the Geography Graduate Group (and on track to receive her doctorate in June 2020), joined the group. Chacon, who studies "habitat connectivity issues for bees at a landscape scale" (see her website on Resilient Bee Landscapes), worked closely with Thorp until his death in June 2019. She is a 2018 alumnus of The Bee Course, co-taught by Thorp.
The first bumble bee to emerge in this area is the black-tailed bumble bee, Bombus melanopygus. 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.
With the dawn of the new year and weather permitting, Jones, Zamzow and Chacon make individual bee-lines for the manzanita plants in the UC Davis Arboretum and Public Garden. Me? I head over to Benicia where bumble bees forage on rosemary or jade.
"Surprising to see males this early in the season," noted Thorp, who co-authored the books, Bumble Bees of North America: An Identification Guide and California Bees and Blooms: A Guide for Gardeners and Naturalists. "Unusual to see males before any workers are on site. Could be from a gyne that overwintered but was not mated before she went into hibernation; or maybe the sperm she received were not viable; or maybe she was unable to release sperm from her spermatheca to some eggs as they passed through her reproductive tract."
"At any rate," Thorp told Jones, in congratulating him, "you got two firsts for the season at one time."
In 2018, yours truly scored by photographing a B. melanopygus on Jan. 1 in Benicia--on rosemary at the marina.
In 2019, Chacon triumphed on Jan. 10 with an image of B. melanopygus, on manzanita blossoms at the UC Davis Arboretum. She earlier spotted one on Jan. 9 in the Arboretum but had no camera with her.
Professor Thorp, a member of the UC Davis entomology faculty for 30 years, from 1964-1994, achieved emeritus status in 1994 but continued to engage in research, teaching and public service until a few weeks before his death. He co-taught The Bee Course from 2002 to 2019. Held annually at the Southwestern Research Station, Portal, Ariz., this is an intensive nine-day workshop affiliated with the American Museum of Natural History and draws scientists from all over the world. It's geared for conservation biologists, pollination ecologists, and other biologists who want to gain greater knowledge of the systematics and biology of bees. This year's dates are Aug. 16-26; the deadline to apply is March 1.
Sadly, this year's Yolo-Solano bumble bee contest won't be the same without the legendary Robbin Thorp.
In his memory, we've renamed the contest, the Robbin Thorp Memorial Bumble Bee Contest. He would have liked that.



- Author: Kathy Keatley Garvey
Several UC Davis bumble bee enthusiasts--encouraged by native pollinator specialist Robbin Thorp, UC Davis distinguished emeritus professor of entomology--compete every January to find the first bumble bee of the year in Yolo and Solano counties.
It's a friendly competition. Gamers include Allan Jones, Gary Zamzow, both of Davis, and yours truly.
We have a winner!
Drum roll...
On Thursday, Jan. 10 doctoral student Kim Chacon photographed a black-tailed bumble bee, Bombus melanopygus, on manzanita blossoms in the UC Davis Arboretum and Public Garden.
What a delightful find! And in between the rain drops!
This species is native to western North America, ranging from California to British Columbia and as far east as Idaho. It's commonly found on manzanitas, wild lilacs, wild buckwheats, lupines, penstemons, clovers, and sages, among others.
Chacon actually spotted an earlier bumble bee on Jan. 9 at 2:10 p.m. in the UC Davis Arboreutm, but had only her cell phone with her that day. It was a Bombus melanopygus on Arbutus in the Ericaceae section.
She captured some images with her cell phone, but "there was a big downpour about 15 minutes and I didn't bring my good camera, so I went home for the day. I know from my research that this particular location in the Arboretum is a hot spot for bees. The banks and flowering vegetation get plenty of sun. There are three possible spots in the Arboretum, according to my research, and this one had blooming flowers first."
But on Jan. 10, "I woke up determined to get good photos with my good camera!" She walked over to the Ericaceae section again in the Arboretum and spotted a Bombus melanopygus at 3:58 p.m. (See photos below)
Chacon, a UC Davis PhD student in geography, studies "habitat connectivity issues for bees at a landscape scale."
"Lack of habitat connectivity is listed as the main reason for native bee declines and yet, thus far solutions only include stand alone gardens, with randomly spaced unspecified plant species," she commented. "A spatial habitat problem such as destruction and fragmentation needs a spatial solution. I am working on solving this complex problem with the help of Geographic Information Systems (GIS). Part of my research involved weekly monitoring bee visitation of bees throughout the UC Davis Arboretum for one full year. I learned about the trends of bee-flower visitation within each unique themed garden, specifically, how they function as novel ecosystems. When I graduate I hope to design effectively connected landscape habitat for bees. I would also love to design educational gardens, showcasing bee diversity!"
Chacon is a 2018 alumnus of The Bee Course, a nine-day intensive workshop affiliated with the American Museum of Natural History and held annually at the Southwestern Research Station, Portal, Ariz. It's offered for conservation biologists, pollination ecologists, and other biologists who want to gain greater knowledge of the systematics and biology of bees. This year's dates are Aug. 18-28, and the deadline to apply is March 1, 2019.
Thorp is one of the veteran instructors of The Bee Course; he has taught there annually since 2002. A member of the UC Davis entomology faculty from 1964 to 1994 and internationally recognized for his expertise on bees, he achieved "distinguished emeritus professor" status in 2015. He co-authored the UC California book, California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday) and Bumble Bees of North America: An Identification Guide (Princeton University Press).
Thorp continues his research, writings and bee identification at his office in the Harry H. Laidlaw Jr. Honey Bee Research Facility at UC Davis.



