Seen any bumble bees lately?
No? Me, neither.
It's almost the first day of spring, and bumble bees are as scarce as the proverbial hen's teeth. (Hens have no teeth, y'know.)
We've been watching our nectarine tree bloom. It's drawing honey bees, but no bumble bees.
Back on March 18, 2018, we spotted a number of bumble bees, including Bombus melanopygus, also known as the black-tailed bumble bee. This is one of the 27 species of bumble bees in California. We frequently see the yellow-faced bumble bee, Bombus vosnesenskii, and sometimes Bombus californicus, aka the California bumble bee.
Our March 18, 2018 "poster child" on our nectarine tree, Bombus melanopygus, appeared to be nesting nearby, due to her frequent visits.
National Public Radio reported on Feb. 6, 2020 that bumble bees are declining because of the extreme heat: "Extreme temperatures are driving a dramatic decline in bumble bees across North America and Europe, according to a new study, in yet another way climate change is putting ecosystems at risk.
"Researchers looked at half a million records showing where bumble bees have been found since 1901, across 66 different species. They found that in places where bumblebees have lived in North America, you're about half as likely to see one today. The decline is especially pronounced in Mexico, where bumble bees once lived in abundance."
Pesticides and habitat loss are also key factors. Says National Geographic in a Feb. 6, 2020 article titled Bumble Bees Are Going Extinct in a Time of 'Climate Chaos': "Climate change is not the only factor behind the insects' decline. They are also threatened by pesticides like neonicotinoids—which are extremely toxic to all bees—destruction of habitat by development and conversion of wildlands into agriculture, the spread of pathogens, and the release of non-native bees for commercial pollination."
If you're interested in learning more about bumble bees, check out the book, California Bees and Blooms: a Guide for Gardeners and Naturalists, the work of UC Davis and UC Berkeley scientists, including Robbin Thorp (1933-2019), distinguished emeritus professor of entomology at UC Davis, who also co-authored Bumble Bees of North America: an Identification Guide.
And if you see any bumble bees in your backyard in your yard between July 23 and Aug. 1, join the Third Annual Backyard Bumble Bee Count at https://www.inaturalist.org/projects/backyard-bumble-bee-count
As inaturalist.org says on its website: "Each bumble bee record submitted during the Backyard Bumble Bee Count helps researchers learn more about how bumble bees are doing and how to protect them and the environment we share. All observations collected July 23- August 1 will be included. For more information, including instructions, go to: https://backyardbbcount.wixsite.com/bumblebeecount."
Have you ever pulled up a chair in your garden and watched honey bees foraging?
They are so intent on their "bees-ness" that they don't know you're there. It's a great opportunity to photograph them.
Sometimes, if you're lucky, they'll buzz over your head on their way back to their colony, and you'll see:
- The three main body parts: head, thorax and abdomen
- The two pairs of wings
- The three pairs of legs
- The pair of antennae
Such was the case in Vacaville this week when we were watching honey bees forage in our African blue basil, a bee magnet that we plant annually. We first learned of African blue basil, (Ocimum kilimandscharicum × basilicum 'Dark Opal'), through Gordon Frankie, UC Berkeley professor and the late Robbin Thorp, distinguished emeritus professor of entomology at UC Davis. They co-authored the book, California Bees and Blooms: a Guide for Gardeners and Naturalists (Heyday Books) with Rollin Coville and Barbara Ertter, also affiliated with UC Berkeley.
Want to know more about honey bees? Be sure to read the newly published The Art of the Honey Bee; Shaping the Environment from Landscapes to Societies (Oxford University Press) by noted bee geneticist and biologist Robert E. Page Jr., who maintains strong ties to UC Davis and Arizona State University (ASU). Also learn about honey bee anatomy on ASU's web page, "Ask a Biologist."
Page, who holds a doctorate in entomology from UC Davis, is a former chair of the UC Davis Department of Entomology. In 2004, Arizona State University (ASU) recruited him for what would become a series of top-level administrative roles. He advanced from director of the School of Life Sciences to dean of Life Sciences; vice provost and dean of the College of Liberal Arts and Sciences; and university provost. Today he holds the titles of provost emeritus of ASU and Regents professor emeritus, as well as UC Davis department chair emeritus, professor emeritus, and UC Davis distinguished emeritus professor.
Did you know a bee has a tool kit? Page lists the tool kit in his book, The Art of the Bee: a compass, an odometer and a path integrator.
'As 'central place foragers,' bees fly out from the nest site and explore the surrounding environment in search of food resources," writes Page, renowned for his research on honey bee behavior and population genetics, particularly the evolution of complex social behavior. "They return to the nest with the resources they collect. To do this, they need to be able to navigate out and find their way back. To aid them, they have a toolkit of navigation mechanisms."
One tool in their tool kit is their internal compass that depends on the location of the sun.
"As light from the sun passes through the atmosphere, it becomes polarized," Page writes. "The pattern of polarized light in the sky depends on the angle of the sun relative to where you are looking. Bees have special sensors in their eyes for detecting the polarized light patterns. On cloudy days, they can't see the sky; but they can still locate the sun using ultraviolet light detectors. Ultraviolet light penetrates cloud cover, allowing bees to use the location of the sun as a navigational marker. With heavy clouds, bees can get to and from a resource by relying solely on landmarks that they learn; otherwise, they stay home until the weather changes. However, as the earth turns, the sun is always changing location relative to the horizon, making it an unreliable marker unless you know the time of day, and bees do. They learn the movement of the sun across the sky and reference it to an internal clock. We know they have the clock because we can train them to forage at specific times of day. If you anesthetize a bee, you can stop her clock. When she awakens and takes a foraging trip to a learned foraging station, her flight path will be offset by the amount of time lost. In other words, she will misinterpret the direction based on the current location of the sun by the amount of time she was anesthetized."
"The odometer plus the ability to determine a flight vector (direction and distance) from a given landmark along a resource flight path, using their sun compass and internal clock, give bees the basic tools for navigation," Page writes. "The last tool in the toolkit is a path integrator that combines the compass and odometer information."
It's a fascinating book by Page, whose most salient contributions to science include constructing the first genomic map of the honey bee, which sparked a variety of pioneering contributions not only to insect biology but to genetics at large.
Meanwhile, take the challenge. Pull up a chair in your garden and watch and photograph the bees going about their "bees-ness."
Have you ever seen a bumble bee sleeping?
If you slip out to your garden at night or early morning, you might find the male bumble bees asleep in, on or around the flowers.
The yellow-faced bumble bee, Bombus vosnesenskii, frequents our pollinator garden in Vacaville, Calif. By day, the bumble bees nectar on African blue basil, Mexican sunflower, lavender, salvia, foxgloves, catmint, honeysuckle, milkweed, California golden poppies and the like. Then at night, when the females return to their nests, the males find a cozy place to sleep.
They may cushion their heads on a Mexican sunflower (Tithonia) or straddle a lavender (Lavendula), holding on with their legs or mandibles.
Oftentimes they'll sleep safely and securely inside a flower that closes at night, such as a California poppy or a torch cactus.
Our Bombus residents seem to prefer the Mexican sunflowers and lavender.
Nighty-night. Sleep tight. Don't let the praying mantids and spiders bite.
Interested in bumble bees? Be sure to read the landmark book, California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday Press). the work of UC-affiliated authors Gordon Frankie, (the late) Robbin Thorp, Rollin E. Coville, and Barbara Ertte.
Thorp (1933-2019), a distinguished emeritus professor with the UC Davis Department of Entomology and Nematology, also co-authored Bumble Bees of North America: An Identification Guide (Princeton University Press).
The distinguished emeritus professor of entomology at the University of California, Davis--he preferred to be known as “Robbin”--was a global and legendary authority on bees, an amazing person and an incredible scientist. He passed away today (Friday, June 7), surrounded by family at his home in Davis. He was 85.
Robbin, 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.
A tireless advocate of pollinator species protection and conservation, Robbin 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.
As Steve Nadler, professor and chair of the UC Davis Department said: “Robbin's scientific achievements during his retirement rival the typical career productivity of many other academic scientists. His contributions in support of understanding bee biodiversity and systematics are a true scientific legacy.”
And as Norman Gary, UC Davis emeritus professor of entomology, commented earlier this year: “Robbin is recognized internationally for his expertise and research on bees, especially non-Apis species, known as wild bees. I doubt that there is anyone else in the world who can compete with his expertise in the systematics of the 20,000 species of bees on this earth. He has the perfect balance of research of field research on the biology and behavior as well as laboratory research on the taxonomy of bees.” He was the go-to person to identify a bee by species.
Yes, he was.
Born Aug. 26, 1933 in Benton Harbor, Mich., Robbin Thorp received his bachelor of science degree in zoology (1955) and his master's degree in zoology (1957) from the University of Michigan, Ann Arbor. Then it was off to UC Berkeley for his doctorate in entomology, awarded in 1964, the same year he joined the UC Davis entomology faculty. He taught courses from 1970 to 2006 on insect classification, general entomology, natural history of insects, field entomology, California insect diversity, and pollination ecology.
In his retirement, Robbin 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). Locally, he was active in research projects and open houses at the Bohart Museum of Entomology and the Häagen-Dazs Honey Bee Haven. In his research, he monitored bees in the Häagen-Dazs Honey Bee Haven, a half-acre bee garden on Bee Biology Road operated by the UC Davis Department of Entomology and Nematology. He established a baseline in 2008 and detected more than 80 species of bees.
On a personal note: I first met Robbin in 2005. He maintained an office in the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road. Although he was “officially retired,” he worked at least 40 hours a week or more--yes, every week--from the time I met him in 2005 through 2018. He'd park his white pickup truck in front of the Laidlaw facility and head eagerly to his office. The bumble bee conservationist decorated his door and office with bumble bee images and posters. He greeted everyone as his friend. After his wife, Joyce, died in December 2018, he shortened his "office hours" at the Laidlaw, but he was always available by computer or phone.
Robbin would identify native bees for everyone—from scientists to students to colleagues to journalists and, frankly, anyone with an interest in bees. And he was delighted to do it. “I enjoy it,” he once told me. And for the same reason, he'd give presentations about native bees throughout much of California and beyond. Often he'd bring along bee specimens and--if one were available--a live male Valley carpenter bee, Xylocopa varipuncta. He called this fuzzy, green-eyed blond "The Teddy Bear Bee" and urged folks to look AND touch. "Boy bees can't sting," he assured them.
An authority on Franklin's bumble bee (Bombus franklini), Robbin began monitoring the franklini population in 1998 in its narrow distribution range of southern Oregon and northern California. He last saw it in 2006 and was instrumental in placing it on the Red List of Threatened Species of the International Union for Conservation of Nature and Natural Resources (IUCN). Folks took notice of his scientific and public awareness efforts. In August of 2016, a documentary crew from CNN, headed by John Sutter, followed him to a meadow where Robbin last saw Franklin's bumble bee. Sutter wrote about Robbin, then 82, in a piece titled "The Old Man and the Bee," a spinoff of Ernest Hemingway's "The Old Man and the Sea."
Next, Robbin sought to place the bumble bee and others on the Endangered Species List. Just last month Fish and Wildlife emailed us that this might occur. Meetings are underway for four petitioned species (B. occidentalis, B. crotchii, B. franklini, and B. suckleyi).
Highly honored by his peers, Robbin was named a fellow of the California Academy of Sciences, San Francisco in 1986; recipient of the Edward A. Dickson Emeriti Professorship of UC Davis in 2010; and recipient of the UC Davis Distinguished Emeritus Award in 2015. Other honors included: member of the UC Davis Bee Team that won PBESA's Team Award in 2013. In addition, he was a past president (2010-2011) of the Davis Botanical Society, and former chair (1992-2011) of the Advisory Committee for the Jepson Prairie Reserve, UC Davis/Natural Reserve System.
In an email today to colleagues, UC Davis doctoral alumnus Leslie Saul-Gershenz, associate director of research, Wild Energy Initiative, John Muir Institute of the Environment, praised his "kindness, his support and his tremendous depth of knowledge. We will all miss the privilege of his friendship and joy of his buoyant personality."
Indeed, we will all miss Dr. Robbin Thorp, scientist extraordinaire, an absolute genius about “everything bees.” But he was much more than that. He was kind, gracious and caring. He was curious, knowledgeable and inspirational. He was the best of the best.
Toward the end of his life, his family read him accolades from his colleagues, researchers, alumni, students and citizenry, and he acknowledged each and every one, smiling. Did he know how much he was loved and appreciated? He did.
Some folks call them "bumble bees," but they're not.
In size, the female Valley carpenter bee (Xylocopa varipuncta) resembles a bumble bee, but certainly not in color.
The female Valley carpenter is solid black with metallic wings. The male of the species is a green-eyed blond, fondly known as "the teddy bear" bee because it's fuzzy-wuzzy and cannot sting. Entomologists will tell you that the male and female are dramatic examples of sexual dimorphism. Yes, they are!
We've been seeing a lot of female Valley carpenter bees lately on our blue spike salvia, (Salvia uliginosa). They engage in nectar-robbing: this occurs when bees circumvent the usual plant-pollinator relationship and "cheat" by entering a flower from the outside to steal nectar. They drill a hole in the corolla to reach the nectar, thus avoiding pollination or contact with the anthers.
Similar-looking insects include bumble bees, cactus flies and horse flies, according to California Bees and Blooms, a Guide for Gardeners and Naturalists,by UC-affiliated authors Gordon Frankie, Robbin Thorp, Rollin Coville, and Barbara Ertter. "Carpenter bees are shinier and have less hair than fuzzy bumble bees. Carpenter bees have two pairs of wings, and they have long, slender, elbowed antennae, while fly mimics have only one pair of wings, and short stubby antennae."
The Valley carpenter bee is California's largest carpenter bee.
They're large but they're elusive. They usually don't linger long for you to grab a photo. This one did. It was early in the morning, and like a true human morning person, she declined to move fast./span>