Let's have a slumber party!

Don't bring a pillow, a night-cap or an attitude—it's Boys' Night Out and we're sleeping outside on the flowers.

That's what the male longhorned bees, Melissodes agilis, do while the females return to their underground nests at night.

"It's a bee B&B," quipped Lynn Kimsey, director of the UC Davis Bohart Museum of Entomology and distinguished professor, UC Davis Department of Entomology and Nematology.

This native species is among California's 1600 species of undomesticated bees.

Ever seen a Boys' Night Out? It's fascinating. The boys curl into a comma, or doze with their heads down and striped abdomens up.  

Over the last two weeks, we've been monitoring the number of males sleeping on a single Mexican sunflower, Tithonia rotundifola, in our Vacaville pollinator garden. On the first night, two. Then three, then four. The slumber party grew to five last night. They sleep on a 10-foot-high blossom (talk about height advantage and a bird's eye view)!  Every night, they return to the very same blossom.

A few years ago we saw the males sleeping on our lavender stems and then they moved to Gaura stems, probably due to the proximity of three praying mantids.

Folks ask if they sting. No. Boy bees don't sting. They can't.

The late Robbin Thorp, distinguished emeritus professor of entomology and co-author of California Blooms and Bees: an Identification Guide for Gardeners and Naturalists, fielded scores of questions on these slumbering bees. “They (males) lack a stinger which is a modified ovipositor in their wasp ancestors. 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. 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."

Of course, not all slumbering bees in this area are Melissodes agilis, as Thorp pointed out. Some may be other species of the genus Melissodes and some may belong to the closely related Svastra obliqua.

The boy bees start arriving for their nightly sleepover around 5 p.m. or when the light fades. Sometimes they appear to be kicking each other before settling down for the night. Said Thorp: "Each establishes his own spot, so there may be some jostling for position initially." 

When it's morning, they rise, warm their flight muscles, sip a little nectar, and begin dive-bombing the honey bees, carpenter bees, bumble bees, butterflies, syrphid flies and assorted other insects on "their" flowers.  M. agilis are very territorial. They're trying to save the food source for the females of their own species—so they can mate with them, as Thorp related.

When their day ends, they cluster for another Boys' Night Out. It's "Nighty Night, Sleep Tight." Time to curl up on a cushion of petals beneath a blanket of stars.

"Bee B&B," as Professor Kimsey says.

It's early morning. 

A newly eclosed Gulf Fritillary, Agraulis vanillae, perches alone in the center of a lavender bed in Vacaville, Calif.  It's too early for the honey bees.

This Gulf Frit probably eclosed at dusk yesterday and then flew several yards from the host plant, Passiflora, to the lavender bed.

As the sun warms her wings, she unfolds them gingerly. As honey bees arrive, buzzing all around her, she moves a few feet.

Eventually she flutters away as more honey bees arrive, a hummingbird hovers over an agave, and California scrub jays chatter.

Just another day in the Life of a Butterfly and another opportunity to showcase this glorious orange-reddish butterfly with silver-spangled underwings.

"This dazzling bit of the New World Tropics was introduced into southern California in the 19th Century--we don't know how--and was first recorded in the Bay Area before 1908, though it seems to have become established there only in the 1950s," writes butterfly guru Art Shapiro,  UC Davis distinguished professor of evolution and ecology, on his research website. He's been monitoring butterfly populations in the Central Valley since 1972. "It can be quite common in the East and South Bay--particularly in Berkeley-- nd has been found breeding spontaneously as far inland as Fairfield where, however, it is not established. There are scattered records in the Central Valley and even up to Folsom, perhaps resulting from people breeding the species for amusement or to release at social occasions. According to Hal Michael, who grew up in South Sacramento, this species bred there in abundance on garden Passiflora in the early 1960s. It seems to have died out by the early 1970s, however. Intolerant of hard freezes, it still managed to survive the record cold snap of 1990 that largely exterminated the Buckeye regionally! In the Bay Area, this species can be seen flying any day of the year, if it is warm and sunny enough.

Yes, flying throughout much of the year. We've seen a Gulf Frit laying eggs on Christmas Day. A gift unlike any other. Early mornings are good, too.

Congrats to the two "Jakes" from the laboratory of community ecologist Rachel Vannette, UC Davis Department of Entomology and Nematology.

The two postdoctoral scholars, Jacob "Jake" Francis and Jacob "Jake" Cecala, have just received prestigious federal research fellowships. And well-deserved!

Francis, a member of the Vannette lab since 2020, received a National Science Foundation (NSF) Postdoctoral Research Fellowship in Biology  (PRFB) to study secondary metabolites in nectar and their consequences for microbes and pollinators. His project is titled “Genetic Signal and Ecological Consequences of Toxic Nectar in Plant-Pollinator Microbe Interactions.”

Cecala, who just received his doctorate from UC Riverside, will join the Vannette lab this fall to study the effects of water availability and pesticide use on bees and bee-microbe associations.

“Jake Francis and Jake Cecala both have impressive track records of impactful and important research on the biology and behavior of native bees,” said Vannette. “The fact that they are being recognized with national funding for their postdoctoral projects is wonderful affirmation of this. Both have proposed timely, novel and exciting projects.  I'm very excited to continue working with Jake Francis to further our understanding of the drivers of so-called ‘toxic' nectar and its impacts on bees and microbes. I very much look forward to Jake Cecala joining the lab and working with him to investigate how pesticides and drought stress interact to influence floral microbes and pollinators."

We wrote more about them on the UC Davis Department of Entomology and Nematology website. These are two amazing young scholars and we expect great things from them.

Francis received his doctorate in 2020 from the University of Nevada, Reno, working with advisor Anne Leonard of the Department of Biology's Program in Ecology, Evolution and Conservation Biology.  He holds a bachelor's degree from the University of North Carolina Asheville (2011) in ecology and evolution, summa cum laude, with distinction as both a research scholar and an honors scholar.

Cecala, who holds a doctorate in entomology (2021) from UC Riverside, was advised by associate professor Erin Wilson-Rankin (formerly of the Louie Yang lab, UC Davis). His dissertation: “Commercial Plant Nurseries as Habitat for Wild Bees.”  He holds a master's degree in biological sciences (2015) from California State Polytechnic University, Pomona, where he completed his thesis, “Bee Visit Frequency and Time of Day Effects on Cumulative Pollen Deposition in Watermelon” with professor Joan Leong, who was a doctoral student of the late Robbin Thorp, UC Davis distinguished emeritus professor.  Cecala was awarded his bachelor's degree in biology, summa cum laude, with a minor in French, also from Cal Poly Pomona. 

Cecala is also a 2013 graduate of The Bee Course, sponsored by the American Museum of Natural History, held annually at the Southwestern Research Station, Portal, Ariz. Professor Thorp served as one of the longtime instructors; his legacy lives on in the next generation of dedicated bee scientists.

The Vannette lab projects are in full force.  Vannette, a former postdoctoral fellow at Stanford University, explains on her website, "the Vannette lab is a team of entomologists, microbiologists, chemical ecologists, and community ecologists trying to understand how microbial communities affect plants and insects (sometimes other organisms. too). We often study microbial communities in flowers, on insects or in soil. We rely on natural history observations, and use techniques from chemical ecology, microbial ecology and community ecology.  In some cases, we study applied problems  with an immediate application including pathogen control or how to support pollinators. Other questions may not have an immediate application but are nonetheless grounded in theory and will contribute to basic knowledge and conservation (e.g. how can dispersal differences among organisms affect patterns of abundance or biodiversity?)."

It's Day 7--the last day--of National Pollinator Week.  Meet a longhorned bee, Svastra obliqua expurgata, family Apidae. It's also known as a sunflower bee.

"It's a bee that prefers sunflower but will collect pollen from a variety of members of the Aster family," the late Robbin Thorp, UC Davis distinguished emeritus professor of entomology and a native pollinator specialist, told us several years ago.

He co-authored the book, California Bees and Blooms: A Guide for Gardeners and Naturalists (along with UC-affiliated colleagues Gordon Frankie, Rollin E. Coville and Barbara Ertter), a must for everyone who wants to learn about bees and blooms.

We remember seeing these native bees nesting underground by the U.S. Bank in Davis in 2015. See Bug Squad blog.

Katharina Ullmann circled the site with yellow caution tape and posted an educational sign. Ullmann, who received her doctorate in 2014 from UC Davis, worked as a national pollinator specialist for the Xerces Society of Invertebrate Conservation before accepting her current position as director of the UC Davis Student Farm in 2017.

"This is a sunflower bee nesting site," wrote Ullmann. "These gentle bees are native and ground nesting. The females of this species are solitary bees, but like to nest near each other and often use the same nest entrance.  Their nesting tunnels lead to individual chambers below the ground. Each chamber is filled with pollen, a single egg, and then closed off. These eggs will hatch, develop underground, and emerge next summer to build their nests. This sunflower bee is one of 1600 species of native bees found in California."

The sign included a "name tag" with the common name, scientific name, favorite food (pollen and nectar), favorite place to be (3rd St., Davis), favorite colors (yellow, red and orange) and favorite saying (YOLO, You Only Live Once).

Ullmann added--and good advice then and now, especially during National Pollinator Week: "Three things you can do to help this bee: (1) protect nests, (2) plant flowers and (3) use fewer insecticides." 

Or better yet, no pesticides.