Today's the Fourth of July and folks are splashing in their pools.
So, what happens when a bee falls in?
Sometimes they get lucky--if there's a human around to rescue them. And sometimes their luck extends to a floating leaf.
This tiny female sweat bee, genus Halictus (probably H. tripartitus, as identified by native polinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis, fell into our pool and then managed to save herself by climbing onto a cherry laurel leaf.
If you look closely, you'll see another sweat bee, an even smaller one, trying to climb onboard, too.
The scenario ended well. The bee coasting along the leaf dried her wings and then flew off.
Luck be a lady...
If you like to take photos of insects that are as small as a grain of rice, then you'll love--absolutely love--stalking a sweat bee.
Sweat bees, members of the worldwide family Halictinae and order Hymenoptera, are so-named because they are attracted to human perspiration or "sweat." They probably lap up perspiration because of the salt content, according to Christopher O'Toole and Anthony Raw, authors of Bees of the World.
The most important of the many genera, the authors say, are Halictus and Lasioglossum, which are common to both the Old World and New World.
Speaking of common, Halictus is also common in bee friendly gardens and swimming pools. Ever gone for a swim and feel a tiny insect sting you? It may have been a sweat bee. ("Their sting is only rated a 1.0 on the Schmidt Sting Pain Index, making it almost painless," according to Wikipedia.)
O'Toole and Raw point out that some sweat bees are only 4mm long, which is why they can be easily overlooked and so difficult to identify.
What's unique are about these ground-nesting bees? The females of all species of sweat bees mate before winter. "This means that, unlike female solitary bees of other families, those of halictids do not have to mate before founding a nest in the spring," they write.
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis, identified this little pollen-packing sweat bee (below) as a female sweat bee, Halictus tripartitus.
She was nectaring a tower of jewels (Echium wildprettii) in our yard and packing a heavy load of blue pollen she'd gathered from the plant.
The tower of jewels is native to the Canary Islands. So, if you visit the Canary Islands, you can probably see--and photograph--this little sweat bee there, too.
When a sweat bee and a honey bee share the same flower, the size difference is quite distinct.
We took this photo of a honey bee on a rock purslane (Calandrinia grandiflora) blossom.
Above it stood a tiny female sweat bee (probably Halictus tripartitus, according to native pollinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis).
Two bees. Two sizes. One blossom. One native. One non-native. The sweat bee is a native, and the honey bee was brought over here in the 1600s by the European colonists.
Speaking of honey bees, this is the first day to participate in TwitCause. The Häagen-Dazs brand is donating $1 per Tweet (up to $500 per day) today through Nov. 11 to support honey bee research at UC Davis.
Häagen-Dazs joined forces with ExperienceProject.com (EP), a San Francisco-based online community for sharing life experiences.
Like to support honey bee research at UC Davis? Go to www.twitcause.com. Directions on top of the page detail how to follow, retweet, and help the honey bee cause on Twitter.
Caught between a rock and a...soft place...
You'll often see tiny sweat bees nectaring rock purslane (Calandrinia grandiflora) in urban gardens. This plant, a native of Chile, brightens landscapes with its pinkish magenta blossoms.You probably wouldn't wear this color if you were in the federal witness protection program. It shouts "Look at me!"
The old saying that "it's so loud it could stop traffic" applies here.
It certainly stops insect traffic. (The lure, though, is the pollen, not the color.)
Last week we watched a tiny female sweat bee (Halictus tripartitus) nectaring the rock purslane.
Then she crawled to the lip of the flower, peered at her surroundings, and took flight.
Scientists have long been studying alternative pollinators, especially with the decline of the honey bee population and growing concerns about "How will we pollinate our crops?"
Now a newly published study in the Annals of the Entomological Society of America (ESA) shows that wild bees, which are not affected by Colony Collapse Disorder (CCD), may serve as alternative pollinators.
You've seen the tiny bees buzzing around on blossoms. At first glance, you may have mistaken them for honey bees. They're not.
Chances are you'll be hearing more about them, though.
ESA's communications director Richard Levine e-mailed us a press release today
reporting the results of a three-year scientific study that took place on 15 southwestern
Most species were from subfamily Halictinae (family Halictidae) and genus Andrena (family Andrenidae)
The journal article, titled "Wild Bees (Hymenoptera: Apoidea: Anthophila) of the Michigan Highbush Blueberry Agroecosystem," was authored by Julianna K. Tuell (
A quote from Tuell in the news release: "This should help growers know what kinds of bees are in the fields so that they can make informed decisions about whether they should modify crop management practices in order to help conserve natural populations of bees."
"Untreated bamboo or reeds are good materials because they provide natural variation in hole diameter to attract the broadest range of species. There are also a number of commercially manufactured options that growers can use, such as foam blocks with pre-drilled holes and cardboard tubes made to a particular diameter to suit a particular species of interest. Drilling different sized holes in wood is another option. If a grower is interested in trying to build up populations of a particular species, there are also details about how to do so available online."
Good idea. On a tour of Yolo County farms last year, we saw many "bee condos," or nesting cavities, for the native pollinators. (See below). They're easy to make. Just like a baseball field attracts players, so will bee condos attract native pollinators. Build them and they will come.
(B y the way ESA now has a presence on Facebook, offering more opportunities for social networking.)
y the way ESA now has a presence on Facebook, offering more opportunities for social networking.)