Posts Tagged: Robbin Thorp
It's time to pop open a bottle of champagne and do a happy dance.
Finally, finally, we saw a yellow-faced bumble bee (Bombus vosnesenskii) in our yard.
After a 20-year absence.
Dusted with yellow pollen, it (or rather he) was nectaring the rock purslane--he, along with assorted honey bees and hover flies.
This Bombus brought to mind the May 27th Webinar that bumble bee expert Robbin Thorp, emeritus professor of entomology at UC Davis presented on "The Plight of the Bumble Bees" at UC Davis.
At the Webinar, he focused on Franklin's bumble bee (range of southern Oregon and northern California) and now feared extinct.
Thorp, a fellow of the California Academy of Sciences since 1986, is a noted authority on bumble bees. In June he served as a key speaker at a public symposium on "The Plight of the Bumble Bees" at the Smithsonian Institution, Washington, D.C. His topic: "Western Bumble Bees in Peril."
Bumble bees need our protection.
As Thorp says: "“The loss of a native pollinator could strike a devastating blow to the ecosystem, economy and food supply."
Yellow-faced Bumble Bee
Cover with Pollen
It's smaller than a honey bee.
And faster and louder.
Anthophora urbana, a solitary, ground-nesting bee, frequents our garden to nectar the catmint, lavender and sage.
Sometimes the forager's buzz is so loud that it's startling. "What was THAT?"
In this case, THAT is a female Anthophora urbana, as identified by UC Davis pollinator expert Robbin Thorp, emertus professor of entomology.
It belongs to the family Apidae, as do honey bees, carpenter bees, cuckoo bees and others. In sheer numbers, it's one of the largest in the Apidae family--more than 450 species worldwide in 14 different subgenera.
It may be tiny, but its buzz isn't.
Catching up with the carpenters is not always easy.
Not the construction workers--the carpenter bees.
They move fast as they buzz from flower to flower.
California is home to three carpenter bee species, says native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis.
You can find Xylocopa varipuncta in the Central Valley and southern California, Arizona, New Mexico and southward through Mexico. It is large (about the size of a queen bumble bee). The females are all black, while the miles are golden/buff-colored with green eyes. The males are commonly known as "teddy bears."
X. californica is right at home in the foothills surrounding the Central Valley, the Transverse Ranges (Los Angeles) of southern California, and areas of Utah, Colorado, New Mexico and Arizona. They are large, nearly the size of X. varipuncta, but with distinctive bluish metallic reflections on their body. Females have dark smokey brown wings.
X. tabaniformis orpifex resides in most of the same areas as X. californica, but extends more into the center of the Central Valley. It is the smallest of the three species--about half the size of the other two carpenter bees. Females are all black with light smokey-colored wings. The males have light yellow hair on their face and thorax.
Carpenter bees, so named for their ability to tunnel through wood to make their nests, carve with their mandibles (jaws) but do not ingest the wood.
Thorp says he tries to convince people to learn to live with these bees as “they are important pollinators in our environment and have potential as pollinators of some crops.”
“Carpenter bees are beneficial in that they pollinate flowers in native plant communities and gardens. That far outweighs any damage to wood structures.”
“These bees are not currently managed for crop pollination,” Thorp said, “but there have been some recent studies of their potential for pollination of greenhouse tomatoes. They are good at buzz pollination and can be managed by providing suitable nest materials.”
Due to their large size, carpenter bees cannot enter tubelike blossoms such as sage, so they slit the base of corolla, a practice known as “robbing the nectar” (without pollinating the flower).
We caught up with two carpenter bees (below) robbing nectar.
Male Carpenter Bee
Female Carpenter Bee
It’s triple-digit hot and you’re relaxing in a swimming pool when suddenly you realize you have company.
A knat-sized insect with a red abdomen lands next to you. It looks like a wasp. No, it looks like a bee. Wait, what is it?
In this case (see photo below), it's a female cuckoo sweat bee from the genus Sphecodes, according to native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis.
Sweat bees are attracted to perspiring skin and often drop into swimming pools where they greet you with a brief but sharp sting.
Sphecodes are cuckoo or parasitic bees. They don’t collect pollen or provide for their young because they don’t need to. They lay their eggs in the nests of other bees. When the larvae hatch, they turn villainous and eat the young of the host bee. They also steal the provisions.
These bees, from the family Halictidae, are really tiny, about 0.2 to 0.6 inches. You’ll see them from late spring until early fall
It’s a large genus, with about 80 known species in the United States and Canada, says entomologist Mace Vaughan of the Xerces Society.
In most species, females are dark red with a shiny abdomen, Vaughan says, while males have a partially or entirely black abdomen.
Call them cuckoo bees. Call them parasitic bees. Call them clepto-parasitic bees. Whatever you call them, you’ll remember that red abdomen and sharp sting.
You'll see red for just a little while.
The Smithsonian Institution is the place to "bee" on Monday, June 22.
The location: Baird Auditorium, National Museum of Natural History. The Smithsonian is located at the corner of 10th Street and Constitution Avenue NW, Washington D.C.
Thorp will discuss "Western Bumble Bees in Peril." Sydney Cameron and Jeff Lozier of the University of Illinois will examine "The Status and Trends of Midwestern and Southern Bumble Bees." Then Leif Richardson of the Vermont Department of Fish and Wildlife will cover "Bumble Bee Trends in Northeastern North America."
- Stephen Buchmann, University of Arizona, "USA Native Bee Diversity: Rarity, Threats and Conservation Ideals"
- Paul Williams, Natural History Museum, London, "A Global View of Bumble Bees and Their Conservation Status."
Michael Ruggiero of the Smithsonian Institution will moderate. He's the senior science advisor of the Smithsonian's Integrated Taxonomic System (ITIS).
Following the symposium, bumble bee experts and other scientists will continue to meet at the Smithsonian for the next two and a half days to discuss concerns about the declining bumble bee population.
The symposium is part of National Pollinator Week, which starts Monday, June 22 and continues through Sunday, June 28.
Thorp delivered a presentation on Franklin's bumble bee May 27, during one of the UC Davis Department of Entomology's noonhour sessions. Franklin's bumble bee, feared extinct or nearing extinction, is found only in one part of the world: southern Oregon and northern California. Thorp's talk was Webcast.
Thorp, a member of the California Academy of Sciences since 1986, says that the loss of a native pollinator "could strike a devasting blow to the ecosystem, economy and food supply."
Locally, we've noticed far fewer bumble bees than in past years. Last summer we spotted a few in the UC Davis Arboretum (see below). This is the yellow-faced bumble bee or Bombus vosnesenskii, the most common Califonria bumble bee.
Not so common any more.
Pollen-Packing Bumble Bee