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>
Ah, pillow fights, popcorn, and marathon movies on TV, you ask?
No. "Boys' Night Out" is when the longhorned male bees in our pollinator garden in Vacaville engage in sleepovers on our Mexican sunflowers (Tithonia) and other blossoms.
At night, the girls sleep inside their nests, and the boys cluster on flowers.
Lately, we've been admiring a trio of boys--Melissodes (possibly M. robustior, as identified by Robbin Thorp, distinguished emeritus professor of entomology at the University of California, Davis)--bunking down on a Tithonia. Every day, around sunset, they head over to the same flower, arrange themselves in comfortable sleeping positions (hey, quit kicking me), and it's nighty-night! When the sun rises, they vacate the bedroom. Sometimes it's earlier than planned, no thanks to buzzing bumble bees, carpenter bees and honey bees foraging around them and disturbing their beauty sleep. The nerve!
Other species of male longhorned bees--including Melissodes agilis and Svastra obliqua--sleep on flowers at night as well.
"Most frequently, the boy bee overnight clusters are single-species clusters," says Thorp, co-author of California Bees and Blooms, a Guide for Gardeners and Naturalists, with UC-affiliated authors Gordon Frankie, Rollin E. Coville, and Barbara Ertter.
Thorp, who holds a doctorate in entomology from UC Berkeley and taught entomology at UC Davis from 1964 to 1994, continues to "bee involved" in research, writings, bee identification and public outreach. He teaches annually at The Bee Course (American Museum of Natural History), at the Southwestern Research Station, Portal, Ariz. The nine-day intensive course is offered for conservation biologists, pollination ecologists and other biologists who want to gain greater knowledge of the systematics and biology of bees.
In a previous Bug Squad blog, Thorp responded to a reader's inquiry about "stings" from the clustering bees. "Boy bees cannot sting," he pointed out. "They lack a stinger which is a modified ovipositor in their wasp ancestors. Occasionally a girl bee may spend the night out if she is caught by sudden drop in temperature. Usually she will not be part of a group sleep over. So don't attempt to handle unless you are confident you can tell boy bees from girl bees or they are too sleepy to defend themselves."
The reader also asked: "Typically how close to the girls' nest(s) do the boys' slumber? I want to try and make sure I don't touch it when planting at end of summer."
"Boy sleeping aggregations are based on a suitable perch and not related to where females are nesting, but probably no more than 100 yards from the nearest female nest," Thorp answered. "Females nest in the ground and have rather distinctive round holes about the diameter of a pencil or slightly smaller, sometimes with small piles of dirt around them looking like mini-volcanos. The holes may be widely separated or clustered together depending on the species, but each female digs her own burrow."
The reader also wondered: "When watching the boys tonight, about ten of them started waking up and kicking each other. They finally settled down and started to nestle back in for the 'night'--it was only 6 p.m.--but I wasn't sure if my presence was getting them riled or they tend to act like kids sharing a bed?"
Said Thorp: "The boys usually settle in as the light dims in the evening. Cool, and drizzly conditions may modify bed time. Each establishes his own spot, so there may be some jostling for position initially."
Longhorned bees are among the more than 1600 species of undomesticated bees that reside in California. In their book, California Bees and Blooms, the authors focus on 22 of the most common genera and the flowers they frequent. Meanwhile, check out Frankie's UC Berkeley Urban Bee Lab website to read more about native bees and the exciting research underway.
What's better than a yellow-faced bumble bee (Bombus vosnesenskii) on yellow mustard?
Not much. Both are signs of early spring.
Mustard is popping up all over, along with oxalyis and wild radish. The earth is warming. Spring is here. Get ready.
In the University of California book, California Bees and Blooms: Guide for Gardeners and Naturalists, the authors write that B. vosnesenskii and B. melanopygus "are considered spring bees because that is when their population is highest, tailing off in numbers the rest of the year."
The book is the work of Gordon Frankie, UC Berkeley entomology professor; Robbin Thorp, distinguished emeritus professor of entomology at UC Davis; photographer and entomologist Rollin Coville (he received his doctorate from UC Berkeley), and botanist Barbara Ertter, also affiliated with UC Berkeley.
Be sure to check out their companion pocket guide on the UC ANR website. It's titled Common Bees in California Gardens. It will help you identify 24 of the most common bees found in urban gardens and landscapes. That's 24 out of nearly 1600 species of native bees found in the Golden State.
Yellow-faced bumble bee, yellow mustard, Golden State....Life is good...
It's spring and it's loud in the Spanish lavender patch.
The girls--the honey bees--are buzzing furiously as they forage among the blossoms, but so are the boys, in this case the mountain carpenter bee, Xyclocopa tabaniformis orpifex. The girls are there for the pollen and nectar to take back to their colonies, and the boys are there for some flight fuel. And to find mates.
Xyclocopa tabaniformis orpifex is one of three species of California carpenter bees: the others are Xyclocopa varipuncta (the largest one, about the size of a bumble bee), and Xyclocopa californica. All females are mostly black. The male Xyclocopa varipuncta, aka "the teddy bear bee," is a golden with green eyes. The other males often have yellow hair on their head or thorax.
The carpenter bees usually fly from March through October, according to California Bees and Blooms, A Guide for Gardeners and Naturalists, a University of California production featuring the work of Gordon Frankie Robbin Thorp, Rollin Coville, and Barbara Ertter (Thorp is a distinguished emeritus professor of entomology at UC Davis, Frankie is a professor at UC Berkeley, and Coville and Ertter are also affiliated with UC Berkeley).
A handy identification pocket guide--a companion to California Bees and Blooms--is Common Bees in California Gardens, published by the University of California Agriculture and Nature Resources. It will help you identify 24 bees and you can lean about the distribution, flight season, nesting habits, floral hosts and how each bee species transports pollen. You'll see beautiful images by noted photographer Coville, who holds a Ph.D. in entomology from UC Berkeley.
Excellent publications! The more you know about bees, the more likely you are to protect them and plant for them.
Ah, spring! It's loud in the Spanish lavender patch...
Might As Well Be Spring
"I'm as restless as a willow in a windstorm
I'm as jumpy as puppet on a string
I'd say that I had spring fever
But I know it isn't spring."--Frank Sinatra
Wait, it is spring!
Today is the day we've all be waiting for--the first day of spring.
If you're lucky, you'll see bumble bees nectaring on spring flowers, including nectarine blossoms.
We spotted this bumble bee, Bombus melanopygus, also known as a black-tailed bumble bee, heading toward our nectarine tree and foraging on the blossoms.
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 little buddy, Bombus melanopygus, appears to be nesting nearby due to her frequent visits to the nectarine blossoms. Hmm, wonder if she is occupying a rodent hole or maybe an old birdhouse....
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, distinguished emeritus professor of entomology at UC Davis, who is also the co-author of Bumble Bees of North America: an Identification Guide.