Posts Tagged: sweat bees
It's St. Patrick's Day tomorrow and time for "The Wearing of the Green."
"The Wearing of the Green" is actually an Irish street ballad dating back to the Irish Rebellion of 1798. The author: anonymous. The color of choice: green. Members of the Society of United Irishmen wore green shamrocks to display their loyalty to the rebellion.
Now take insects. Tomorrow, if you're lucky, you might see some "wearing of the green." But not likely, unless you're visiting a museum and see pinned specimens. The metallic green sweat bees, Agapostemon texanus, aren't out yet in this part of the country.
Very striking, they are. The females are all green. The males are partly green; their head and thorax are green, but not their abdomen.
Still, Saturday, March 17 is a good day to think green!
Male green sweat bee, Agapostemon texanus, nectaring on a seaside daisy, Erigeron glaucus Wayne Roderick at Tomales Bay. (Photo by Kathy Keatley Garvey)
Close-up of metallic green sweat bee, a male. (Photo by Kathy Keatley Garvey)
Female metallic green sweat bee, Agapostemon texanus, at the Haagen-Dazs Honey Bee Haven on Bee Biology Road, UC Davis. (Photo by Kathy Keatley Garvey)
Mother's Day, insect-style, dawned like any other day. In our back yard, golden honey bees foraged in the lavender and those ever-so-tiny sweat bees visited the rock purslane.
The honey bees? Those gorgeous Italians.
The sweat bees? Genus Lasioglossum, as identified by native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis. He figures the female sweat bee (below) may be L. mellipes, which is brownish toward the tips of the hind legs.
A trip to Benicia yielded a photo of a ladybug chasing aphids. It was almost comical. A fat aphid appeared to be playing "King of the Hill" while other aphids sucked contentedly on plant juices, unaware of pending predators.
While the aphids wreaked havoc on a very stressed Escallonia (fast-growing hedge in the family Escalloniaceae), the ladybugs, aka lady beetles, wreaked havoc on some very stressed aphids.
After all, "stressed" spelled backwards is "desserts."
Italian honey bee foraging on lavender. (Photo by Kathy Keatley Garvey)
Sweat bee (genus Lasioglossum) visiting rock purslane. (Photo by Kathy Keatley Garvey)
Ladybug, aka lady beetle, chasing aphids. (Photo by Kathy Keatley Garvey)
Häagen-Dazs Honey Bee Haven at the Harry H. Laidlaw Honey Bee Research Facility on Bee Biology Road, University of California, Davis, is a study in diversity.
Bees, including honey bees, bumble bees, carpenter bees, leafcutter bees and sweat bees, along with other pollinators, share the pollen and nectar in the half-acre bee friendly garden.
Native pollinator specialist Robbin Thorp, emeritus professor of entomology, has logged some 50 different species of bees in the garden since its inception. He began a baseline monitoring process when the garden was a field of weeds, instead of dreams.
Today we spotted a yellow-faced bumble bee (Bombus vosnesenskii)
and a honey bee sharing a purple coneflower (Echinacea purpurea). Minutes later, a honey bee and a sweat bee occupied another coneflower.
The garden, planted last fall, changes daily, which it is meant to do. When the grand opening celebration of the haven takes place from 10 a.m. to 2 p.m. on Saturday, Sept. 11, expect to see scores of visitors--both humans and pollinators--sharing the garden.
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.
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.)