So there we were, checking out the bumble bee mimics (Anthophora bomboides stanfordiana) on May 9 at Bodega Head, Sonoma County, and along buzzes a pollen-packing Habropoda miserabilis, the bee that UC Davis doctoral alumnus Leslie Saul-Gershenz studies.

The female bee was literally making a "bee-line" for the mustard and wild radish. Bee research scientist John Ascher identified it.

We remember when Saul-Gershenz lent her expertise to the "long lost" silver digger bees found in March of 2019 in the newly restored sand dunes at the San Francisco Presidio.  The Presidio, a former military post, is now owned and operated by the National Park Service.

An authority on digger bees, Saul-Gershenz confirmed to the National Park Service officials that they are H. miserabilis and were probably common in the sandy dunes of that area as late as the 1920s. When non-native ivy, eucalyptus and ice plants took over their habitat, the bees disappeared.

“The discovery of a thriving native bee colony on the western side of the Presidio is the latest example of how the removal of invasive plants and the restoration of dunes and grasses at the former military base have helped bring back coastal habitat that thrived in San Francisco for tens of thousands of years before the city was built,” said Saul-Gershenz, formerly a research scientist with the U.S. Department of Agriculture (USDA) Agricultural Research Service.

“I am very happy to see this nest site at the Presidio,” she told us at the time. She's worked on the biology, chemical ecology and parasite interactions of this group of bees in the genus Habropoda for many years--on research trips that have taken her to the Oregon coast and the Mojave desert, among others.

She and several colleagues are completing a paper on H. miserabilis on its distribution and host plant use in western United States: "Habropoda miserabilis Cresson (Hymenoptera: Apidae): Floral Habits, Distribution, and Nesting Biology."

“This nest parasite M. franciscanus was originally described from the dunes in San Francisco near Lake Merced by Van Dyke in 1928,” Saul-Gershenz related. “It is presumed to be locally extirpated in San Francisco due to habitat alteration. However, its host bee, H. miserabilis,  appears to have finally found a suitable nest location in a sand dune area being restored by the Presidio Trust in the Presidio National Park.  The resiliency of nature provides hope for the future.”

In a news story published in the San Francisco Chronicle on March 29, 2019, science reporter Peter Fimrite quoted the UC Davis-trained entomologist as saying that the silver digger bees were “all but gone” by the mid-20th century.  However, Saul-Gershenz has kept looking for them. In fact, she collected one near Baker Beach in 1998.

With restoration, comes hope for the return of native plants and insects.

"Biologists have reported a more than tenfold increase in the number of native plants in the Presidio, including at least four that are federally listed endangered or threatened, among them the Presidio clarkia," wrote Fimrite. "The Franciscan manzanita, which was believed to be extinct in the wild, was discovered in the Presidio in 2009. It was the first of its kind seen in its native San Francisco since the old Laurel Hill Cemetery was bulldozed in 1947 and paved over for homes."

Gershenz and collaborator Jocelyn Millar of UC Riverside and others deciphered the sex attraction of Habropoda miserabilis and the deceptive mimicking blend used by its nest parasite Meloe franciscanus working with a population on the coast of Oregon (Saul-Gershenz et al. 2018). They documented a new parasite-host location system while conducting research on related species in the same genus Habropoda pallida found in the Mojave and Sonoran Desert (Saul-Gershenz and Millar 2006).

The comeback of silver digger bees is not limited to San Francisco. Fimrite related that several other areas in California are witnessing comebacks, including Bodega Marine Reserve in Bodega Bay and Lanphere Dunes in the Humboldt Bay National Wildlife Refuge. 

Yes, they are. 

"Sweat bees have earned their common name from the tendency, especially of the smaller species,to alight on one's skin and lap up perspiration for both its moisture and salt content."

So write University of California scientists in their award-winning book, California Bees and Blooms, a Guide for Gardeners and Naturalists.

California has some 1600 species of undomesticated or wild bees, point out the authors (Gordon Frankie, Robbin Thorp, Rollin Coville and Barbara Ertter).

And one of them is the sweat bee, Halictus ligatus, a  member of the family Halictidae. It's a medium-sized, ground-nesting bee with a striped abdomen.

This week one of these species (as identified by research scientist John Ascher) looked especially striking on a Black-Eyed Susan, Rudbeckia hirta, a member of the Aster (Asteraceae) family.  Both the plant and the bee are natives.

Several years ago we managed to photograph a flameskimmer dragonfly, Libellula saturata, munching on one of these sweat bees. Not a good day for that little gal!

No dragonflies were around, however, when we watched this one foraging on a Black-Eyed Susan. 

Did you know that the Black-Eyed Susan is the designated state flower of Maryland? And that it was the inspiration for the University of Southern Mississippi's school colors (black and gold)? And that it's a larval host to butterflies such as the bordered batch, gorgone checkerspot and silvery checkerspot?

Who knew? If you plant it, though, be aware that it is toxic (when ingested) to cats.

If you want to learn about bees--and learn it from the experts--The Bee Course is the place to be.

It's an annual workshop held at the Southwestern Research Station (SWRS) in Portal, Ariz. for conservation biologists, pollination ecologists, and other biologists "who want to gain greater knowledge of the systematics and biology of bees," according to organizer Jerome Rozen Jr. of the American Museum of Natural History (AMNH), New York.

AMNH launched the course at SWRS in 1999.  This year's nine-day workshop will take place Aug. 25-Sept. 4.

Native pollinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis, has been teaching at the workshop since 2002. Thorp, who received his doctorate in entomology from UC Berkeley, served on the UC Davis faculty from 1964 to 1994, but although he officially "retired" in 1994, he never really did. He continues his research, writings and bee identification at his office in the Harry H. Laidlaw Jr. Honey Bee Research Facility at UC Davis.

Frankly, we at UC Davis don't know what we'd do without him. Thorp maintains a massive educational, research and public service work that brings national and worldwide pride and distinction to UC Davis. No one can say “pollinators” without thinking of Thorp.  For example, MacArthur Foundation Fellow Claire Kremen, a conservation biologist with the UC Berkeley Department of Environmental Science, Policy and Management, said she would never have attempted her much-cited Yolo County pollinator project without his expertise. He not only helped develop the protocol, but he identifies all the species—about 60,000 of them since 1999.  

“He is a fully engaged collaborator in statewide research projects to quantify the effects of pollinator habitat enhancement in farm landscapes to promote sustainable pollination for California agriculture, and has been instrumental in the research," said Neal Williams. associate professor in the UC Davis Department of Entomology. “Robbin is not only involved in others' research, but is a world leader in bumble bee ecology and conservation.  His recent efforts to monitor western bumble bees are often cited as the catalyst behind regional and national efforts to conserve endangered bumble bees.”

Robbin Thorp will turn 80 years young during The Bee Course. Shhh--don't tell anyone.  (P.S., he says it's okay to "tell.")

Thorp and his colleague John Ascher, an assistant professor at the National University of Singapore and research associate at the American of Natural History, New York, and a key scientist at BugGuide.Net, were working today at the Bohart Museum of Entomology at UC Davis. We captured a quick image of them (below).

Ascher, who received his doctorate in entomology from Cornell University, has taught at The Bee Course since 2004. 

The Bee Course textbook is The Bee Genera of North and Central America, Michener, C.D., R.J. McGinley and B.N. Danforth, 1994, Smithsonian Press.

Why in Portal, Ariz.? It's one of the richest bee faunas in North America.

All the instructors are volunteers.  In addition to Rozen, Thorp and Ascher, the 2013 team includes Stephen Buchmann of Tucson, who received his doctorate in entomology from UC Davis; James H. Cane and Terry Griswold of the USDA-ARS Bee Biology and Systematics Lab at Utah State University, Logan; Lawrence Packer of York University, Toronto, Canada; and UC Davis alumnus Ronald McGinley of Dewey, Ill. (he obtained his doctorate in entomology from UC Berkeley and then worked at Harvard University and the Smithsonian before joining the Illinois Natural History Survey).

The participants, usually around 22, come from all over the world. They will return home with a collection of properly labeled bee specimens--and a comprehensive knowledge about bees.

From the website: The course "emphasizes the classification and identification of more than sixty bee genera of North and Central America (both temperate and tropical), and the general information provided is applicable to the global bee fauna. Lectures include background information on the biologies of bees, their floral relationships, their importance in maintaining and/or improving floral diversity, inventory strategies, and the significance of oligolecty (i.e., taxonomic floral specialization). Field trips acquaint participants with collecting and sampling techniques; associated lab work provides instruction on specimen identification, preparation and labeling."

And the course significance: "The field of pollination ecology explores the reproductive biology of plants in general, including the biotic and abiotic agents associated with pollination and seed-set. This is of interest for basic research and understanding of world communities and also has significant practical impact as it relates to pollination of economically important crop plants, to survival of endangered plants, and to plant reproduction in threatened habitats. Pollen is moved between receptive flowers by wind, water, birds, bats, beetles, flies, etc., but the 20,000 species of bees worldwide play a dominant role in the sexual reproduction of most plant communities. This course will empower students with 1) the confident use of The Bee Genera of North and Central America, 2) an appreciation for the biological diversity of bees, and 3) sufficient background to learn more about bees and investigate pollination and conservation problems with greater insight."

Said Thorp: "It is a great experience for students to interact with instructors and especially with their peers from around the world.  Instructors all donate their time to teach in the course, but benefit from the chance to get together with colleagues and a new cohort of interesting students each year.  Every class is different. that is, it takes on its own personality, and each student brings something new and different to the mix."