So here's this lady beetle patrolling a rosebud. It's early spring--April 15--in Vacaville, Calif.--and our little subject is looking for some tasty aphids. Or perhaps a mate.
Oh, a visitor is on my rosebud, heading right toward me. Identify yourself, please!
It's a wasp, a male parasitic wasp from the family Ichneumonidae (as identified by Robbin Thorp, distinguished emeritus professor of entomology at UC Davis).
The Ichneumon wasp is probably looking for a girlfriend. The lady beetle does not meet its expectations.
The wasp hurriedly flies off. Its mate, when it finds one, will lay her eggs in caterpillars, including such pests as armyworms, cabbage loopers, tomato fruitworm and tussock moths, much to the delight and appreciation of agriculturists. The eggs hatch into larvae, which develop inside the host, killing it. Adult wasps emerge and the cycle continues.
The wasp family is aptly named. "Ichneumon" comes from the Greek word meaning "tracker," a reference to its search for a host. Where's a caterpillar when you need one?
Charles Darwin seemed a bit troubled by this, describing these parasitic wasps as "feeding within the living bodies of caterpillars." The caterpillar shrivels up and dies.
Ichneumonidae is a big, big family of feeders. The number of described species? More than 24,000 worldwide. However, "estimates of the total species range from 60,000 to over 100,000--more than any other family in the order Hymenoptera," according to Wikipedia. That's probably more than any other family in the insect world, or for any other family, for that matter.
Says BugGuide.net: "They vary greatly in size and color; many are uniformly colored, from yellowish to black and others are brightly patterned with black and brown or black and yellow; many have middle segments of antennae yellowish or whitish. The majority resemble slender wasps but differ from the stinging wasps (Scolioidea, Vespoidea and Sphecoidea) in having longer antennae with more segments (usually at least 16). Many have long ovipositors, often longer than the body."
"Ichneumonids are notoriously hard to identify: aside from the sheer number of species, there are numerous cases of distant relatives that appear almost identical," BugGuide points out. "Any identification based solely on comparing images should be treated as suspect unless an expert has said there are no lookalikes for the species or group in question."
Have you checked to see what's foraging on your early spring blooms?
Our cherry laurels (Prunus laurocerasus) are blooming and the Andrena (mining) bees are zooming. These fast-moving bees are solitary ground-nesting bees that are early spring bees, according to native pollinator specialist Robbin Thorp, distinguished emeritus professor of entomology at UC Davis. The males emerge first.
"Females emerge several days later and, with only a few short weeks to live, waste no time with polite introductions," write and Thorp (who received his doctorate in entomology from UC Berkeley) and UC Berkeley professor Gordon Frankie in California Bees and Blooms: A Guide for Gardeners and Naturalists. The book is also co-authored by UC Berkeley affiliates: entomologist/photographer Rollin E. Coville and botany specialist Barbara Ertter.
"Mating is first on their agenda, followed by a quick meal of pollen to build up their ovaries," Thorp and Frankie point out. "They then dig or forage for materials to construct their nests, and for food for their offspring. At the end of the short flight season, the adults die and the new generation's life cycle continues inside the nest."
Thorp identified the bees below as two females: Andrena candida and A. nigrocaerulea. He and several colleagues teach The Bee Course, "an annual workshop for conservation biologists, pollination ecologists and other biologists who want to gain greater knowledge of the systematics and biology of bees." It's held at the Southwestern Research Station, Portal, Ariz., and this year's dates are Aug. 21-Aug. 31.
"Most North American Andrena species are black, dull metallic blue, or green and moderately hairy, with bands of pale hair on their abdomens," according to the Xerces Society for Invertebrate Conservation. "Females have large, velvety facial depressions (foveae) that look like eyebrows and large pollen-collecting hairs (scopae) on the upper part of their hind legs, seemingly in their 'armpits.' Despite a variety of striking colorations, Andrenan species are difficult to tell part."
If you have sandy soil and shrubs, that's ideal for them. You'll be the landlord and they'll be your tenants. "They nest in the ground, typically in sandy soil and often near or under shrubs. The nest entrance is usually marked by a small mound (tumulus) of soil."--Xerces Society.
Andrena is the largest genus in the family Andrenidae, with more than 1300 species, and about 261 in California. They occur nearly worldwide (Americas, Eurasia and the Old World tropics). The tiniest of the Andrena are only 7 millimeters long.
You may not see them. They're as tiny as they are fast, and they don't stop for photographs!
Sometimes you get lucky...
Despite other major attractions--including the gorgeous spring day and the March Madness basketball tournament--nearly 300 people visited the UC Davis Bohart Museum of Entomology last Saturday during its three-hour open house, themed "Eggs to Wings: Backyard Butterfly Gardening."
They conferred with Lynn Kimsey, director of the Bohart Museum and professor of entomology at UC Davis; Robbin Thorp, distinguished emeritus professor of entomology; Tabatha Yang, education and outreach coordinator; and a number of Bohart associates, including entomologist Jeff Smith, who curates the moth and butterfly display; naturalist Greg Kareofelas, a butterfly and dragonfly enthusiast; entomologists Jessica Gillung and Ziad Khouri, doctoral candidates; Nicole Tam, junior specialist; and Joel Hernandez and Alex Nguyen, recent entomology graduates.
"Hungry, hungry caterpillars!" read one poster, illustrated with photos of the monarch, gulf fritillary and pipevine swallowtail caterpillars and their adult stages. "Having a garden full of flowers provides nectar, an important food source for adult butterflies, but what about their hungry, hungry caterpillars? It seems counterintuitive to grow plants that yu want insects to eat, but that is exactly what butterflies need when they are larvae."
Jeff Smith kept busy showing visitors the drawers of butterfly specimens, including blue morphos, monarchs and swallowtails. As he opened one drawer, he explained that "this drawer contains several species of South American rainforest butterflies, Preponas, in the genus Archaeoprepona." He described them as "extremely strong and fast fliers, but they love to settle on baits such as fermenting fruit on the ground. We (Bohart team) caught several in the ongoing Belize biodiversity work this past year."
Robbin Thorp showed live male Valley carpenter bees, Xylocopa varipuncta, green-eyed blond bees that are also known as "teddy bear" bees. "Boy bees can't sting," Thorp said, reassuring a few leary visitors. The female of the species is solid black. (Following the open house, Thorp returned the bees to the UC Davis Department of Entomology and Nematology's Häagen-Dazs Honey Bee Haven on Bee Biology Road.)
The bottle is tucked inside a zipped, meshed butterfly habitat and placed indoors or in a screened patio to prevent tachinid flies and wasps from laying their eggs in the caterpillars or chrysalids. Once the monarchs pupate and eclose, they are released to start another generation. This is a small-scale conservation project.
The Bohart Museum's regular hours are from 9 a.m. to noon and 1 to 5 p.m. Mondays through Thursdays. The museum is closed to the public on Fridays, Saturdays and Sundays and on major holidays. Admission is free. Special open houses take place throughout the academic year. The next open house takes place during the annual campuswide Picnic Day on April 22.
More information on the Bohart Museum is available by contacting (530) 752-0493 or email@example.com. The website is http://bohart.ucdavis.edu/
Native pollinator specialist Robbin Thorp, distinguished emeritus professor of entomology at UC Davis, greeted a visitor on Feb. 14 in his office in the Harry H. Laidlaw Jr. Honey Bee Research Facility.
This visitor didn't talk, though. She buzzed.
And she buzzed right over to his window.
Well, hello, black-tailed bumble bee, Bombus melanopygus!
"Guess all one needs to do is sit and wait," he wrote in an email to bumble bee enthusiasts. "Eventually a gyne will find her way into one's office. This one was buzzing against my window just a few minutes ago trying to get back outside."
She came to the right place.
Thorp, a noted expert on bumble bees, is the co-author of Bumble Bees of North America: An Identification Guide (Princeton University) and California Bees and Blooms: A Guide for Gardeners and Naturalist (Heyday). He also teaches at The Bee Course, an annual workshop hosted by the American Museum of Natural History at the Southwestern Research Station, Portal, Ariz. (The Bee Course is meant for "conservation biologists, pollination ecologists and other biologists who want to gain greater knowledge of the systematics and biology of bees," according to the website. This year's course is Aug. 21-31.)
The black-tailed bumble bee, native to North America, is one of only 250 species worldwide in the genus Bombus.
What's next with Thorp's bumble bee?
A nest box in an almond tree near the Laidlaw facility--feed her some honey, make her feel at home, "then let her fly out, hopefully to return and establish a nest."
Insect photographer and naturalist Allan Jones of Davis discovered and photographed three Bombus melanopygus foraging on manzanita on Jan. 27 in the UC Davis Arboretum. In doing so, he won the science-based, friendly competition among a small group of bumble bee enthusiasts in Yolo and Solano counties searching for the first bumble bee of the year.
But Allan Jones went looking for his bumble bee; Thorp's bumble bee came to him...
Arthur Shapiro, distinguished professor of evolution and ecology at UC Davis, annually sponsors the "Beer for a Butterfly" contest, offering a pitcher of beer for the first cabbage white butterfly (Pierae rapae) of the year found in the three-county area of Sacramento, Yolo and Sacramento. He launched the contest in 1972 as part of his long-term studies of butterfly life cycles and climate. This year he again won the contest; he collected a newly eclosed butterfly at 1:56 p.m. Thursday, Jan. 19 near the Solano Park Apartments on the UC Davis campus.
But where's the first bumble bee of the year in the Yolo county area?
At 2:02 today (Friday, Jan. 27) naturalist and insect photographer Allan Jones of Davis alerted us: "Two Bombus melanopygus on manzanita just east of the redwood grove (UC Davis Arboretum)."
And then he found another melanopygus. It was a three-in-one day.
The story behind the story: five years ago, a small group of keen-eyed bumble bee aficionados (Robbin Thorp, distinguished emeritus professor of entomology at UC Davis and co-author of Bumble Bees of North America: An Identification Guide; and three naturalists and insect photographers Gary Zamzow and Allan Jones of Davis, and yours truly of UC Davis) launched our own contest.
In an unusual twist, Jones found both genders at the same time. After finding and photographing two males just east of the Arboretum's redwood grove, he spotted and photographed a female just west of it.
"Surprising to see males this early in the season," noted Thorp, who co-authored the book, California Bees and Blooms: A Guide for Gardeners and Naturalists. "Unusual to see males before any workers are on site. Could be from a gyne that overwintered but was not mated before she went into hibernation; or maybe the sperm she received were not viable; or maybe she was unable to release sperm from her spermatheca to some eggs as they passed through her reproductive tract."
"At any rate," Thorp told Jones, in congratulating him, "you got two firsts for the season at one time."
Great job, Allan Jones! And the bumble bee season begins...