Sometimes they barely notice you.
Such was the case of a yellow-faced bumble bee, Bombus vosnesenskii, spotted on our Mexican sunflower (Tithonia).
If a picture is worth a thousand words, what is a bee worth?
If you want to learn more about bumble bees, be sure to check out the landmark book, Bumble Bees of North America, an Identification Guide, co-authored by our own Robbin Thorp, distinguished emeritus professor of entomology at the University of California, Davis. It's the first comprehensive guide to North American bumble bees to be published in more than a century.
Thorp is one of the veteran instructors at The Bee Course, held annually at the Southwestern Research Station in Portal, Ariz. This year's course is Aug. 20-30. (The deadline to apply was March 1.) It's a nine-day intensive workshop offered for conservation biologists, pollination ecologists, and other biologists "who want to gain greater knowledge of the systematics and biology of bees."
The Anise Swallowtail, Papilio zelicaon, fluttered into our pollinator garden and headed straight for the Verbena.
Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, identified the gender: "it's a girl."
The Anise Swallowtail, our first sighting of the season, bypassed the butterfly bush, Buddleia davidii.
But she'll be back--hopefully to gather some more nectar and lay her eggs on our fennel.
The Verbena patch was a little too populated for her liking--honey bees and yellow-faced bumble bees, Bombus vosnesenskii, wanted their share of the nectar, too.
"The Anise Swallowtail is a complex set of ecological races, or 'ecotypes,' whose seasonality has been adjusted by natural selection to match that of their host plants," says Shapiro on his research website. He's studied butterfly populations in central California since 1972.
"In multivoltine populations the spring brood is typically small, pale, heavily marked with blue and with narrow dark borders on all wings. Summer individuals are larger, with richer yellow color, broader black borders and little or no blue in males. Univoltine populations tend to be intermediate between these extremes. The small larvae resemble bird droppings. Large larvae are pale green with black bands containing orange spots; in hot, dry sites there is more green and less black, while under cool, humid conditions the green may even disappear! The pupae may be brown or green."
Read more about the swallowtail, including its food sources, on Shapiro's web page.
Meanwhile, whether you see your first Anise Swallowtail of the season or the last of the season, you'll want to see more of this yellow-mellow butterfly!
It was billed as the second annual Butterfly Summit, hosted last Saturday by Annie's Annuals and Perennials in Richmond.
But a yellow-faced bumble bee, Bombus vosnesenskii, foraging on Anchusa azurea (a member of the borage family), apparently didn't like the focus on butterflies.
Butterfly Summit? How about a Bumble Bee Summit?
For several minutes, we watched this industrious bumble bee zip in and out of the Anchusa. It zig-zagged between a Delphinium Cobalt Dreams and a Linaria triornithophora, Three-Birds Flying.
With her heavy load of orange pollen, she appeared to be bogged down, perhaps too heavy to fly?
We remember National Public Radio running a piece on "Heavy Loads of Pollen May Shift Flight Plans of the Bumble Bee," which aired in August of 2015. NPR's Nell Greenfieldboyce drew attention to research by biologist Andrew Mountcastle of Harvard University, work published in the Proceedings of the National Academy of Sciences.
"Despite what you may have heard, bumble bees do not defy the laws of physics when they fly," Greenfieldboyce related.
Fact is, they just fly differently than airplanes. "They flap their wings, and their wings bend and twist as they flap them," Mountcastle told her. He said that when bumble bees carry a pollen load, rather than a nectar load, "they are more stable, but less maneuverable in flight."
Bottom line: bumble bees are very good at flying, even when they're loaded with cargo (pollen).
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...
Bring on the bumble bees!
In yesterday's Bug Squad blog, we mentioned the unusual first-of-the-year bumble bee sightings at the Benicia Capitol State Historic Park. We captured images of the yellow-faced bumble bees, Bombus vosnesenskii, nectaring on jade, Crassula ovata, the morning of Jan. 1, 2018. They were packing cream-colored pollen.
Bombus vosnesenskii were also out and about at the Benicia Marina--same morning, same day--but on a different floral species: rosemary, Rosmarinus officinalis. This flower, too, yields a cream-colored pollen.
But wait! The bumble bees we saw foraging on the rosemary were packing orange pollen, as bright as Halloween pumpkins.
What happened? They didn't get it from the rosemary. It came from another plant, perhaps the early blooming California golden poppies which yield orange pollen (and no nectar).
Rosemary, which blooms nearly year-around in this area, belongs to the mint family, Lamiaceae, which also includes peppermint, spearmint, basil, lavender, marjoram, germander, thyme, savory, and horehound. One of the distinguishing features in this family: square stems.
When you think about it, rosemary's presence at the marina is quite appropriate. It derives its name from the Latin "dew" (ros) and "sea" (marinus), or "dew of the sea."