When you install bee condos--those wooden blocks with holes drilled in them to attract nesting native bees--sometimes you get the unexpected.
Home invasion! Home invasion!
We installed two bee condos, each about the size of a brick, in our yard. One is for leafcutting bees (genus Megachile) and is filled quite nicely, thank you, with 10 tenants. Another, with larger holes, is for blue orchard bees (BOBs, genus Osmia). Despite our "vacancy" sign (discounted rates, free WiFi, free continental breakfasts), nothing is occupying it except earwigs.
Earwigs! We're wigged out.
They were especially persistent in the damp weather.
Native bee guru Robbin Thorp, a native pollinator specialist and emeritus professor of entomology at the University of California, Davis, who has researched native bee holes with colleagues John Barthell and Gordon Frankie, told us: "We found that mostly wasps and earwigs occupied the largest holes. Only a few of the introduced leafcutting bees that could not find appropriate size holes when bee populations were abnormally high would make aberrant nests in the larger cavities. By 1990, we scaled back to the three diameters that our bees use: 4.5, 6.5 and 8 mm (3/16, 1/4, and 5/16 inch) for our studies in California."
The earwigs, Thorp says, "are not so likely to be present now that the weather is hot and dry, but in shady, damp, cool areas, and especially early in the year when it is wet and cool, they can be a problem."
Their research, published in Environmental Entomology in 1998 and titled “Invader Effects in a Community of Cavity Nesting Megachilid Bees (Hymenoptera: Megachilidae)” involved native bee species and their introduced competitors.
In their paper, they wrote that the European earwig (Forficttla auricularia L) from Eurasia and northern Africa, was introduced into North America at the turn of the century. "It has invaded most counties in the state of California since its apparent introduction in the late 1910s (Essig 1923, Langston and Powel! 1975)," they wrote. "Its populations have grown to high numbers in natural areas, especially in riparian zones where humidity levels are relatively high (Barthel! and Stone 1995). The earwig is most active during evening hours, climbing into tree crowns to scavenge and hunt but hiding in cracks, crevices, or holes during the daylight hours."
Active indeed. Those European earwigs soon found our condo for BOBs (which perhaps should now mean Big ol' Blast).
What's a picnic without bugs? What's a county fair without bugs?
If you meander through McCormack Hall at the Solano County Fair, Vallejo, you'll see plenty of insects. The Bohart Museum of Entomology at UC Davis is staffing a table of "Meet Your Local Pollinators," including butterflies, bees and bee mimics. Tabatha Yang, education and outreach coordinator at the Bohart Museum (home of seven million insect specimens) also brought along honey bee photos, posters and other information from the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Department of Entomology.
The museum specimens include two "oh-my!" drawers (that's what people say when they see these fascinating displays); a collection of native bees from UC Davis graduate student Emily Bzdyk; and California butterflies. Accompanying the display is a framed poster of California's state insect, the California dogface butterfly, the project and design of Fran Keller, UC Davis doctoral candidate in entomology. Davis naturalist-photographer Greg Kareofelas scanned the butterfly images.
But be sure to look on the walls where young photographers and graphic artists are displaying their blue-ribbon work. You'll see honey bees, dragonflies, butterflies and other insects. Future entomologists, perhaps?
A three-year-old named Nicholas Razo of Dixon created a colorful paper butterfly, the kind that UC Davis butterfly expert Art Shapiro probably would like to see in real life. Young Nicholas may give Professor Shapiro some competition in a few years.
The fair, which opened today (Aug. 3) and continues through Aug. 7, is themed "There's No Place Like Home."
There's no place like home for us--and the insects who populate the earth.
The declining bee population: Does chlorine in a swimming pool have anything to do with it?
Ever since PBS NewsHour correspondent Spencer Michels interviewed Extension apiculturist Eric Mussen of the UC Davis Department of Entomology and several other UC scientists and bee folks on the declining honey bee population, it's been busy on the bee front.
Everyone seems to have a theory on the cause of colony collapse disorder (CCD) and why the bee population is declining.
One person, known as "DK," posted a comment on the PBS NewsHour site that maybe chlorine has something to do with it.
"Every morning, when I sweep (skim) the family pool here in Sherman Oaks (Los Angeles), Calif., at least 3-4 bees from a hive in a nearby hedge are dead in the water, and I don't think it's from drowning," DK wrote. "It's like the La Brea Tar Pits were eons ago: The sparkling pool looks like potable water, but it just lures them to their deaths...When I "googled" this subject, it turned out a farmer in the San Joaquin valley who was experiencing colony collapse discovered that a neighboring farmer was using a chlorine based pesticide in his irrigation water on the adjacent watermelon patch; when I read further into it, the article said chlorine was a suspected 'neuro-toxin" for the bees, and that corresponds with my empirical observations. The chemical component also might explain why only 25% of bee colonies are experiencing this problem."
"So, scientists in northern California and elsewhere, that's your clue: CHLORINE (and its derivatives). It's worth a look."
Mussen, a noted expert on honey bees, responded:
"I read with interest your concern about a possible connection between chlorine and our honey bee problems. I believe that you are correct that honey bees actually prefer a bit salty water to pure water, so they might be attracted to your swimming pool water. However, honey bees do not like to get their feet wet when collecting water, if they can help it. They stand on the dry and drink from the film of water caused by capillarity. If you find one drinking water near your pool, on the poll apron, pool wall or a floating toy, check their behavior.
"The bees you find in the pool probably were not there for drinking purposes. You noted that you have a colony living nearby. Each day that colony raises about 1,000 newly emerging adult workers and around six weeks later those 1,000 bees will die of old age. They do not die in the hive. They tend to keep foraging until they flutter to the ground (lawn, driveway, sidewalk, pool, etc.) wherever they may be. Those bees are not yet dead, so for a little while they still can sting if bumped against or stepped on. That is most likely why they keep ending up in your pool.
"In reference to your statement about chlorine in pesticides harming a beekeeper's bees, there have been a succession of pesticides with chlorine incorporated into their structures that are toxic to bees. The group named organochlorides are pretty much obsolete, but a new group of chemicals, called neonicotinoids, have a chlorine in them. Beekeepers fear those compounds because they become systemic in the plants and are found in the nectar and pollen when the plants bloom. Recently, the systemics have been delivered in irrigation water, since they can be picked up from the soil by the plant roots. In 'chemigation' with underground emitters, you would think that the chemicals would stay away from the bees. But, the systems leak and the bees will forage at the junctions in the pipes and from puddles on the ground. So, the bees get the chemical at field delivery concentrations, not at the much reduced concentrations that end up in the blossoms."
Speaking of water, as any beekeeper will tell you, bees don't like to get their feet wet. Honey bees don't dive into a pool on a hot summer day. They don't head for the sprinklers for a quick shower. They don't stand in water. When they collect water to cool their hives, they stand on the very edge of a water-filled container, such as a birdbath or the lip of a flower pot.
Which reminds us: a recently published children's book (for ages 4 to 10) about honey bees seemed to have it all: colorful illustrations, catchy lines, and educational information about bees.
One look at an illustration, though, and it's apparent that neither the author nor the illustrator know that much about water and honey bees. The illustration clearly shows honey bees walking in water. Three of them. Three of them happily walking in a water-filled birdbath.
"What's wrong with this illustration?" I quizzed a veteran beekeeper. He looked at me as if I'd just asked him the second letter of the alphabet.
"Bees," he said, "don't like to get their feet wet. Those bees in that illustration are walking in water. They don't do that."
No, they don't.
Gotta love those dragonflies in the family Libellulidae.
The Thunderbirds of the insect world, they perform amazing aerial maneuvers as they skim over water, catching mosquitoes, knats, flies and other undesirables on the wing.
But oh--occasionally they nail a pollinator.
A red flame skimmer (Libellula saturata) skimmed over our fish pond and pool last Saturday and picked on the pollinators. Well, at least one pollinator.
It grabbed a female sweat bee, of the genus Halictus, probably H. tripartitus (as identified by native pollinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis, and Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis).
Yes, they can even identify a mangled sweat bee in the mouth of a dragonfly.
And no sweat bee.
That very word summons a smile.
A public celebration--appropriately titled “Honey!”--will take place Friday, Oct. 21 in the UC Davis Conference Center.
Save the date!
The event, sponsored by the Robert Mondavi Institute for Wine and Food Science, will include tastings and a honey-focused lunch.
“Bees play a crucial role on our planet from pollinating to honey creation,” said Clare Hasler-Lewis, executive director of the institute, which is affiliated with the UC Davis College of Agricultural and Environmental Sciences.
The public is invited to “come celebrate with us and enjoy lectures, tastings and displays on honey,” she said.
The event is scheduled to include the history of honey and its use across the ages; honey as a food incorporating honey in your diet; and honey for health, from balancing blood sugar to wound healing.
Among the UC Davis speakers:
--Liz Applegate of the UC Davis Department of Nutrition faculty. A national expert on nutrition and fitness, she will discuss the health benefits of honey.
--Brian Johnson of the UC Davis Department of Entomology faculty. Johnson, who specializes in the behavior, genetics and evolution of honey bees, as well as apiculture, will explore the history of honey use across the ages.
--Extension apiculturist Eric Mussen of the UC Davis Department of Entomology. A nationally known expert on honey bees and honey, he will lead a honey tasting.
As plans progress, additional information will be posted on the Robert Mondavi Institute for Wine and Food Science website, Facebook and on Twitter.
Ah, sweet October!