Meet the competitors.
In this corner, meet Mr. Teddy Bear. He's a blond, green-eyed carpenter bee, Xylocopa varipuncta, a native, and one of three species of carpenter bees commonly found from northern to southern California to western New Mexico.
In the other corner, meet Mr. Bodyslam. He's a European wool carder bee, Anthidium manicatum, a native of Europe. His "immigrant ancestor" was first detected in the United States (New York) in 1963, and the species spread west. The carder bee (so named because the female "cards" fuzz from plants for her nest) was first recorded in California (Sunnyvale) in 2007.
The competitors meet on foxglove, Digitalis purpurea, which yields dramatic pink-purple fingerlike flowers (and medicine for heart patients).
Mr. Teddy Bear is famished. He's doing what entomologists call "nectar robbing." He's drilling a hole in the corolla and drinking nectar, bypassing the usual plant-pollinator relationship. He's grabbing the reward and "cheating" by entering the flower from the outside, avoiding contact with the anthers.
Mr. Bodyslam is territorial. He's patrolling the foxglove patch--HIS foxglove patch--trying to save the nectar for his own species so he can mate with them. When he sees intruders, he targets them.
So here's Mr. Teddy Bear, drilling and sipping, sipping and drilling. Life is good.
"Hey, get away from my flowers and nobody gets hurt! They're mine!"
"Hey, I'm bigger than you. Get lost."
And the battle begins.
The winner, in this corner, Mr. Teddy Bear. He successfully avoided contact by crawling between the flowers (where Mr. Bodyslam couldn't reach him) and then sneaking to the corolla.
But once--just once--contact erupted. Ouch!
He's the bully in the bee garden.
If you've ever watched the male European wool carder bee (Anthidium manicatum) patrolling "his" flower patch, you'll see him targeting insects several times larger than he is.
Take the case of the Valley carpenter bee (Xylocopa varipuncta), one of the largest bees in California. The female is solid black, while the male is a green-eyed blond.
Last week we were watching female Valley carpenter bees trying to gather some nectar from a bluebeard (Caryopteris x clandonensis) when the much smaller male carder bee dive-bombed her.
The male was also dive-bombing and body-slamming honey bees, sweat bees leafcuter bees and other bees, in addition to butterflies. They do that to "save" the flowers for their own species and perchance to mate!
As the sun set, the sleepy male carder bees headed over to a bee condo to grab some shuteye.
The bee condo was meant for nesting blue orchard bees (which pollinate the almonds in the spring).
Bee condos can also be occupied by other critters, including spiders, wasps and European wool carder bees!
Do they ever slow down?
The male European wool carder bee (Anthidium manicatum), a yellow and black bee about the size of a honey bee, spends most of the day defending its "property" (food) from other visitors. It's so territorial that it will dive-bomb and/or bodyslam visitors such as honey bees, butterflies, sweat bees, carpenter bees, bumble bees and praying mantids that dare land on or occupy "their" plant. We've seen them do this on catmint, blanket flower, Mexican sunflower, foxgloves and bluebeard.
If you're a floral visitor, it's no fun trying to sip some nectar while trying to dodge a yellow-and-black bullet. And if you don't move, you're likely to get hit. Unexpectedly.
Early morning, however, is a perfect time to photograph the male carder bees. They're often resting on a blossom, warming their flight muscles, or sipping a little nectar.
The bees, so named because the females collect or "card" leaf fuzz for their nests, were introduced in New York in 1963, and then began spreading west. They were first recorded in California (Sunnyvale) in 2007.
"Males are considerably larger than females, and have a spine on either side of the last two abdominal segments and three spines on the last segment," says Lynn Kimsey, director of the Bohart Museum of Entomology and a professor of entomology at UC Davis. Those spines have been mistaken for stingers, but only females have stingers.
The female wool carder bees build their nests in rotting wood or preexisting tunnels, such as beetle burrows, Kimsey says. At night, we've seen the males sleeping in the bee condos (drilled blocks of wood) meant as homes for blue orchard bees.
A little R&R before D&B (dive-bombing and body-slamming).
(Note: Check out the Anthidium manicatum research in Pan-Pacific Entomologist, the work of entomologist Tom Zavortink, associate at the Bohart Museum of Entomology, UC Davis, and entomologist Sandra Shanks, formerly of Davis and now Port Townsend, Wash. They pointed out that several papers “have documented its spread from neighboring areas in the northeastern United States and southern Canada” and that the species has since crossed the country. It was confirmed in Colorado in 2005, Missouri in 2006, and Maine, Michigan, Maryland and California (Sunnyvale) in 2007, the entomologists wrote.)
I've been waiting for a decade to see a male Valley carpenter bee (Xylocopa varipuncta) foraging in our family bee garden.
The girls? Oh, yes. We see them every day. Sometimes half a dozen at a time. They're usually on the salvia or passionflower vine.
The boys? No. They do not go where our girls are. I saw a solo fly-by a couple of years ago, but he did not stop.
Then last Saturday, a male Valley carpenter bee dropped down and nectared on the foxgloves (Digitalis purpurea), the dwarf bulbine (Bulbine frutescens), the catmint (Nepeta) and the blanket flower (Gaillardia x grandiflora).
In that order.
To be honest, a very territorial European male carder bee (Anthidium manicatum) chased him off the foxgloves, so our big boy headed for the catmint and then the blanket flower, where he encountered only docile honey bees.
The male Xylocopa varipuncta is the insect that results in so many similar calls--"I found a golden bumble bee! Is it a new species?" A bumble bee it is not. A carpenter bee it is.
Native pollinator specialist Robbin Thorp, distinguished emeritus professor of entomology at the University of California, Davis, calls the male Valley carpenter bees "teddy bears." That's because they're green-eyed, blond and fuzzy-wuzzy. Thorp reminds curious kids and apprehensive adults that "boy bees can't sting."
Thorp often displays a female Valley carpenter bee (solid black) alongside the blond male to show the sexual dimorphism, or what Wikipedia explains is a phenotypic differentiation between males and females of the same species.
The Boy Wonder is sort of like a blond Marilyn Monroe male courting a Clarkette Gable.
What happened when the Boy Wonder left the blanket flower? He returned to the foxgloves.
Just briefly. Until the wool carder bee targeted him again.
She described it to a "T."
That would be "T" for territorial.
Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis, spotlighted the European wool carder bee in her current edition of the Bohart Museum Society newsletter.
The males are aggressive. Their territorial behavior is "in your face." They will chase away bees, butterflies and even small birds, like hummingbirds. "They will also check out humans, flying up to them and hovering," Kimsey says.
But it's not something we should be worried about. The wool carder bee is a pollinator.
"We tend to think of all exotic species of insects as being pests," Kimsey wrote. "By and large, that's true but there are exceptions. The wool carder bee, Anthidium manicatum, may be one of these exceptions."
She describes it as a species of European leafcutter bee "that has successfully colonized North America. However, North America isn't the only place these bees have invaded. They are now found in north Africa, South America, Asia, the Canary Islands and even in New Zealand. World domination is ahead."
The wool carder bee (so named because the female scrapes or cards leaf fuzz for her nest) was accidentally introduced into the U.S. from Europe in the early 1960s and was first discovered in New York State. It spread quickly across the continent. Scientists found it in Davis, Calif., in 2007.
They're about the size of a honey bee, Kimsey says "but they are brightly marked with yellow on a black background with a bright yellow face. Only honey bees in Disney movies are black and yellow. Males are considerably larger than females, and have a spine on either side of the last two abdominal segments and three spines on the last segment."
Those spines have been mistaken for stingers, but only females have stingers.
We've seen the males protect patches of lamb's ear, catmint, foxgloves, oregano, cosmos, African blue basil, and Mexican sunflower (Tithonia) in our yard. They mean bees-ness. We've seen honey bees working frantically, trying to forage as quickly as possible without getting targeted. We've also seen some of them crippled on the ground.
The female wool carder bees build their nests, Kimsey says, in rotting wood or preexisting tunnels, such as beetle burrows.
Kimsey mentioned that the Bohart Museum scientist Tom Zavortink experienced female carder bees "carding" wool from his socks!
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