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A Bee That's a Delight to See

Male green metallic sweat bee. (Photo by Kathy Keatley Garvey)
What's that on the Coreopsis?

Could it be--a bee?

Yes, that's the metallic green sweat bee, also called an ultra green sweat bee, Agapostemon texanus.  This one  (below) is a female. Males and females are easily distinguishable.  The female is all green, from head to thorax to abdomen, while the male (right) is green on the head and thorax but not on the abdomen.

Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, talked about them at the recent UC Davis Pollinator Gardening Workshop, sponsored by the California Center for Urban Horticulture.

The Agapostemon are members of the Halictinae family. They are "often called sweat bees because in hot weather they are attracted to human perspiration, which they lap up, probably for the salt it contains," according to the book, Bees of the World, by Christopher O'Toole and Christopher Raw.

Some of the family's many genera, including  Agapostemon, are restricted to the New World. Halictus and Lasioglossum "are common to the Old and New Worlds," the authors write.

Coreopsis, also called tickseed or coreopsis, is a genus of flowering plants in the family Asteraceae.

We spotted the female metallic green sweat bee at the Loch Lomond Marina, San Rafael. We captured the image of the male several years ago on a seaside daisy at the Mostly Natives Nursery, Tomales.

Green sweat bees will be among the bees featured in the book, "California Bees and Blooms: A Guide for Gardeners and Naturalists," to be published in the fall of 2014 by Heyday Press. It's the work of Gordon Frankie of UC Berkeley; Robbin Thorp of UC Davis; photographer Rollin Coville of the Bay Area; and Barbara Ertter of UC Berkeley. It will contain nearly 30 of the most common bee genera in California.

Frankie, Thorp, Coville and Ertter (and others) also published "Native Bees Are a Rich Natural Resource in Urban California Gardens" in California Agriculture.

Female metallic green sweat bee, Agapostemon texanus, on coreopsis. (Photo by Kathy Keatley Garvey)
Female metallic green sweat bee, Agapostemon texanus, on coreopsis. (Photo by Kathy Keatley Garvey)

Female metallic green sweat bee, Agapostemon texanus, on coreopsis. (Photo by Kathy Keatley Garvey

Female metallic green sweat bee peers at the photographer. (Photo by Kathy Keatley Garvey)
Female metallic green sweat bee peers at the photographer. (Photo by Kathy Keatley Garvey)

Female metallic green sweat bee peers at the photographer. (Photo by Kathy Keatley Garvey) Keatley Garvey)

Posted on Tuesday, April 22, 2014 at 8:01 PM

Rapini! Rapini! Rapini!

Billy Synk in the rapini he planted. (Photo by Kathy Keatley Garvey)
Honey bee population declining?

You wouldn't know it if you were to visit the two rapini patches in front of the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road, University of California, Davis.

“The bees love the rapini,” said Laidlaw manager and staff research associate Billy Synk, who planted the seeds given him by Project Apis m.

Project apis m., a moniker derived from Apis mellifera, the scientific name of the European honey bee, funds and directs research to enhance the health and vitality of honey bee colonies while improving crop production. It's based in Paso Robles, Calif.  Take a look at the organization's website:  "We've infused over $2.5 million into bee research since our inception in 2006 to provide growers with healthier bees resulting in better pollination and increased crop yields.  We have personal relationships with the nation's commercial beekeepers and with the top bee scientists in the country."

"We fund research studies, purchase equipment for bee labs at our universities, support graduate students and provide scholarships to young bee scientists to encourage their pursuit of science-based solutions to honey bee challenges." 

Its eight-member board includes beekeepers and industry leaders. Extension apiculturist Eric Mussen of UC Davis is a longtime scientific advisor.

And rapini? It's a green cruciferous vegetable from the mustard family. The leaves, buds and stems are edible and often served in restaurants throughout the world. If you were in Italy, you'd eat the cimi di rapa or rapini. In Naples, it's known as friarielli and sometimes broccoli di rapa, according to Wikipedia. If you were in Rome, broccoletti. And in Portugal and Spain, grelos.

The bees know it as simply food for their colonies. Good stuff.  (In addition to rapini, PAm encourages folks to plant lovers, vetch, allysum, and native wildflowers as bee pasture.)

One thing's for certain: If you plan to participate in the UC Agriculture and Natural Resources' pollinator count for a three-minute period on Thursday, May 8 your eyes will tire from counting all the bees in the rapini!

Like to participate?  See the UC ANR's website, Day of Science and Service. You can also photograph pollinators and post the images on the website for all to see and enjoy.

A honey bee foraging on rapini at the Harry H. Laidlaw Jr. Honey Bee Facility. (Photo by Kathy Keatley Garvey)
A honey bee foraging on rapini at the Harry H. Laidlaw Jr. Honey Bee Facility. (Photo by Kathy Keatley Garvey)

A honey bee foraging on rapini at the Harry H. Laidlaw Jr. Honey Bee Facility. (Photo by Kathy Keatley Garvey)

Honey bee takes a liking to the rapini.  (Photo by Kathy Keatley Garvey)
Honey bee takes a liking to the rapini. (Photo by Kathy Keatley Garvey)

Honey bee takes a liking to the rapini. (Photo by Kathy Keatley Garvey)

Multi-tasking honey bee cleaning its tongue and packing its pollen load. (Photo by Kathy Keatley Garvey)
Multi-tasking honey bee cleaning its tongue and packing its pollen load. (Photo by Kathy Keatley Garvey)

Multi-tasking honey bee cleaning its tongue and packing its pollen load. (Photo by Kathy Keatley Garvey)

A large pollen load. (Photo by Kathy Keatley Garvey)
A large pollen load. (Photo by Kathy Keatley Garvey)

A large pollen load. (Photo by Kathy Keatley Garvey)

Posted on Monday, April 21, 2014 at 9:48 PM

An Un-bee-lievably Generous Gift

Debra Jamison (center), state regent of the California State Society of the Daugthers of the American Revolution and Karen Montgomery (far right), state regent project chair, present the check to haven manager Chris Casey. (Photo by Kathy Keatley Garvey)
What an un-bee-lievably generous gift!

Debra Jamison, state regent of the California State Society of the Daughters of the American Revolution. loves bees. So when it came time to select a fundraising project, she knew what she wanted to do.

Jamison adopted the motto, “Bees are at the heart of our existence” and vowed to support honey bee research and enhance honey bee environments to help the beleaguered bees.

Jamison, whose first name means “bee” in Hebrew, says she's had a lifelong “love and respect for bees.” Her project? She chose to help bee research at the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road at the University of California, Davis, and support the adjacent Häagen-Dazs Honey Bee Haven, owned and maintained by the UC Davis Department of Entomology and Nematology.

Last year Jamison and her fellow members of the California State Society donated $30,000 to bee scientist Brian Johnson. Then this year they gifted $15,000 to the garden, which was planted in 2009 as a year-around food resource for the Laidlaw bees and other pollinators. It also serves to create public awareness for the plight of bees, and as an educational garden, where visitors can glean ideas for their own gardens.

The check was presented at a “lunch-with-the-bees” celebration organized by the UC Davis College of Agricultural and Environmental Sciences. Some 125 DAR members, some from as far away as Chico and San Diego, dined beneath a canopy of olive trees bordering the road.

“We appreciate this more than we can say,” said Ed Lewis, professor and vice chair of the department--and whose mother belongs to DAR.

On behalf of the department, haven manager Christine Casey accepted the check from Jamison and Karen Montgomery of Modesto, the state regent's project chair. The department used some of the funds to purchase two benches. Other projects will include a shade structure in the Growers Grove section and more bee habitat.

Honey bees prefaced the American Revolutionary War (1765-1783) by 143 years. European colonists brought the honey bee to Jamestown colony, Virginia, in 1622. Descendants of the American Revolutionary War formed DAR in  1890. 

DAR plaque on a bench in the garden. (Photo by Kathy Keatley Garvey)
“When the state regent's project was conceived, I never imagined that honey bees would be in the serious state they are in,” Jamison told the luncheon crowd. “I could not have imagined that this amazing insect would make the cover of Time magazine, or that the California DAR would be involved in trying to do something to help the most vital insect in the animal kingdom.”

“Our 114 chapters and 15 districts have worked diligently to educate members, children, and the public about the plight of bees,” Jamison said. “This outreach has been truly outstanding. Add to that the phenomenal fundraising efforts. I truly thought that when I brought this project before the members that they might think, ‘Eeeeeuuuu, creepy insect, and weird state regent.'

Jamison singled out several DAR members for special recognition. She praised Karen Montgomery, state chair of the project and member of the Major Hugh Moss Chapter, Modesto, and committee members Susan Montgomery of the Major Hugh Moss Chapter; and Diane Groome, Carol Vercellino and Sharon Paukkert, all  of the José Maria Amador Chapter, Pleasanton. “Thank you all, from the bottom of my heart, for all of your work to raise funds for this project,” Jamison said

Jamison presented certificates of appreciation to Extension apiculturist Eric Mussen and communication specialist Kathy Keatley Garvey of the UC Davis Department of Entomology and Nematology for their work in helping DAR with the two-year project.

"Bee Patriotic” rally towels decorated each table. Last year Jamison's rally towels were lettered with “Bee-lieve in the Power of DAR." All those attending the March 28th luncheon received a “I Bee-long to DAR” recyclable grocery bag.

The crowd toured the haven and ended the day with hearing bee presentations in the Laidlaw facility conference room.

Mussen talked about the life cycle of bees and the issues bees face: malnutrition, pesticides, pests, parasites, diseases and stress. Malnutrition, Mussen said, is a bigger problem now than colony collapse disorder (CCD), a mysterious malady characterized by adult bees abandoning the hive.  An active colony of honey bees requires an acre-equivalent of mixed blooms, daily, to meet their nutritional needs.

Mussen urged the DAR members to plant for bees, especially plants that normally bloom in late summer and fall, or delay plantings so that they result in late summer/fall blossoms.  Good plant lists, he said, can be found on the UC Davis Entomology and Nematology's bee biology website (see Honey Bees), and on the Xerces website,  under “Pollinator Conservation Resource Center.”

Mussen also warned that simply because certain pesticides are labeled for use in organic gardening does not mean that they are less dangerous for non-target insects, particularly pollinators.  Also, insecticides that are watered into the soil and move from the roots, systemically throughout the plants, are secreted in the nectar and pollens when the treated plants bloom. 

“We are just studying certain mixes of fungicides, insect growth regulators, and newer adjuvants that can cause serious damage to honey bee brood, even though that information is not on the labels,” Mussen said.

In thanking the DAR members Johnson said the $30,000 will cover a two-year period of graduate student research. His graduate student, Gerard Smith, researches the effect of pesticide exposure in the field on honey bee foraging behavior, and graduate student Cameron Jasper studies the genetic basis of division of labor in honey bees.

The haven is open from dawn to dusk every day. Admission is free. To commemorate National Public Gardens Day, a special event (free) will take place from 5:30 to 7 p.m. on Friday, May 9. It will include a guide tour at 6 p.m. and a give-away of sunflower seeds (while they last).

Debra Jamison (left), state regent, and Gayle Mooney, state treasurer, share a bench that the California State Society of the Daughters of the American Revolution purchased for the UC Davis bee garden. (Photo by Kathy Keatley Garvey)
Debra Jamison (left), state regent, and Gayle Mooney, state treasurer, share a bench that the California State Society of the Daughters of the American Revolution purchased for the UC Davis bee garden. (Photo by Kathy Keatley Garvey)

Debra Jamison (left), state regent, and Gayle Mooney, state treasurer, share a bench that the California State Society of the Daughters of the American Revolution purchased for the UC Davis bee garden. (Photo by Kathy Keatley Garvey)

DAR members celebrating the bees beneath the olive trees on Bee Biology Road. (Photo by Kathy Keatley Garvey)
DAR members celebrating the bees beneath the olive trees on Bee Biology Road. (Photo by Kathy Keatley Garvey)

DAR members celebrating the bees beneath the olive trees on Bee Biology Road. (Photo by Kathy Keatley Garvey)

Posted on Friday, April 18, 2014 at 5:28 PM

Cataloging Insect and Bat Diversity in Belize

Butterfly in the family Hesperiidae, found in Belize. (Photo by David Wyatt)
A unique effort to raise funds to collect insects in the biodiversity hotspot of Belize—which would result in specimens for the Bohart Museum of Entomology at the University of California, Davis, among other goals-- is galloping into the home stretch.

“Our crowd sourcing ends on Sunday night, April 20," said wildlife biologist David Wyatt, professor at Sacramento City College.  (To learn more about the effort or to donate, check out the "Cataloging Insect and Bat Diversity in Belize" website.)

Wyatt, a professor in the field ecology program and a veteran of nine trips to Belize, in Central America, has scheduled the trip for June 2-16, 2014. A veteran of nine trips to Belize, he will guide the research team of six other biologists, including entomologist Fran Keller, his former student. Keller, who is finishing her doctorate in entomology at UC Davis, studies with major professor Lynn Kimsey, director of the Bohart Museum and UC Davis professor of entomology.

In addition to establishing a major entomology collection in Belize, the research team will conduct an inventory of bats from this area of Belize.  An added bonus to the bat work is that the team will be collecting insect ectoparasites from the bats - in particular the bat flies (Nycteribiidae and Streblidae). “These are a fascinating group of parasitic dipterans that only occur on bats with a high degree of coevolution between the bats and the bat flies,” said Wyatt, who specializes in mammals (ringtails and bats) and also extensively studies in entomology.

The researchers are also teaming with the Biodiversity Center of Belize to conduct DNA barcoding of the insect specimens they collect (each will donate a leg to the analysis) and also barcoding of small wing punches of skin from the bats.  Regular updates of the project are being blogged under the Lab Notes section of the website.  Supporters who donate are automatically informed of new Lab Notes updates by email.

Fran Keller
“The trip to Belize is an excellent opportunity but it is also a necessity,” Keller said.  “Belize is a biodiversity hotspot. There is not much known about the diversity of insects in Belize. We will be establishing an entomological collection in Belize that will act as a foundation and reference collection for this region. Not only will specimens be housed in Belize, but many specimens will be brought back to the U.S. to be housed in the Bohart Museum of Entomology and Sacramento City College.”

Keller said that starting an entomological collection “is not an easy thing nor is it inexpensive. With university and governmental cutbacks, funding for basic scientific research, such as biodiversity surveys and discovering new species, is rejected and being replaced by studies focused on climate change and alternative energy resources. Insects act as indicators of climate change and understanding the distribution of insects over time informs the scientific community on how various ecosystems are being altered by climate change.”

“Our crowdsource funding is an attempt to fund research through a unique online company called Experiment.com. We are presenting our research proposal to the public and the public will decide the value by backing the project with donations that range from $5 to--well we will take any maximum amount. Any funds over the requested amount will be applied to the collection set up equipment. With only three days left we are hoping to get as many backers as possible. Getting to work with David to establish this collection in Belize is also an opportunity for a former student to give back to a dedicated mentor.”

Keller is an alumnus of Sacramento City College. She began her academic career as a microbiology major but after completing classes in natural history, entomology, and field entomology, she turned her interests from single-celled organisms to multi-cellular animals. She is now teaching science at the college.  

Keller credited Wyatt with encouraging her to transfer to UC Davis to continue her education.  “David's enthusiasm and energy for teaching and entomology were contagious,” Keller said. “Although I really do enjoy cell and molecular biology, entomology is my true passion and David helped me recognize that fact. David and I have collected insects together many times in the Mojave Desert and Arizona. He also encouraged me to sign up for a one-week course in the summer to work with bats. Many bats rely on insects as their major food source.”

“I guess I have been an entomologist since I was a child but just didn't know it,” Keller said. During her childhood, she collected bees in jars and added flowers "to see what the bees would do." She and her sisters also collected caterpillars and watched them form chrysalids and emerge as butterflies.

Fran Keller chasing dragonflies. (Photo by Alex Wild)
Fran Keller chasing dragonflies. (Photo by Alex Wild)

Fran Keller chasing dragonflies. (Photo by Alex Wild)

David Wyatt with a ringtail.
David Wyatt with a ringtail.

David Wyatt with a ringtail.

Posted on Thursday, April 17, 2014 at 6:15 PM
Tags: bats (1), Belize (1), David Wyatt (1), Fran Keller (16), insects (12)

Targeting the Varroa Mite

Varroa mite on a drone pupa. (Photo by Kathy Keatley Garvey)
Beekeepers know the varroa mite as "Public Enemy No. 1."

And it's an enemy to be reckoned with, Extension apiculturist Eric Mussen told students in the UC Davis "Biology of Parasitism" class, taught by forensic entomologist Robert Kimsey and nematologist Steve Nadler, Department of Entomology and Nematology.

Guest-lecturing at a special session held at the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis, Mussen talked about the varroa mite--its history, biology, damage and control methods--and then opened several hives at the apiary.

The Varroa destructor, a native of Asia, is now found in hives throughout the world except in Australia. It was first detected in the United States in 1987.

The eight-legged reddish-brown parasite, about 1–1.8 mm long and 1.5–2 mm wide, is a blood sucker that's difficult to control, Mussen said. Mites transmit viruses (there are now some 22 named RNA viruses) that can wipe out a hive. A familiar mite-transmitted disease that beekeepers see is DWV or Deformed Wing Virus. Mites are also known lowering the protein level of a bee's blood, and reducing its weight and life span.

Mussen said that mites spread from colony to colony by phoresy (animal-to-animal transport). They ride on flying drones (males) and adult worker bees (females). They also spread changing hosts on flowers.

"A mite enters a honey bee cell just before or during the time it is being capped," Mussen said. "It feeds on older larva or prepupa. Sixty hours later, the mite lays its first egg. The egg will hatch in about 24 hours."

"The number and release of offspring depend on the length of the pupal stage. The queen is pupa for 8.5 days (no mites). The worker is pupa for 12.5 days (1.3 mites) and the drone is pupa for 14.7 days (3 or 4 mites)," he said. Thus, due to the longer time required for drone development, drone pupae get the worst of it.

"When maturing, the newly emerged mites climb onto adult bees and feed by puncturing the intersegmental membranes and sucking the bee blood," Mussen related. "Often these are nurse bees that stay around the brood nest. Sometimes the hosts are drones and older foragers that are flying from the hive every day. Eventually the new mite climbs off the nurse bee onto a comb in the brood nest and enters a cell. The reproductive cycle starts and within 6 days, 44 percent of the young mites have moved into the brood cells; within 12 days, 69 percent of the mites are in the brood cells; and within 24 days, 90 percent of the mite are in the brood cells."

"If there is no brood, the mite has to feed on adult bee blood every six days or so to remain alive," Mussen said. "Mite life expectancy in summer is around 60 days; bees about 42 days. Mite life expectancy in the winter is up to 9 months; bees about six months."

Mussen also discussed how to detect mite infestations through non-chemical and chemical methods,  and listed chemical treatments being used throughout the nation. Mites are developing resistance to a few chemical treatments, he pointed out. And, some of the chemical treatments not only kill the mites, but damage or kill the queen and the brood.

Beekeepers who try to go organic, figuring that "if the bees can't make it on their own--if they're not fit--let them die" are really doing a disservice to neighboring beekeepers, Mussen said. The mite will overrun a colony and then  infest other colonies.

Public Enemy No. 1--definitely a force to be reckoned with.

Extension apiculturist Eric Mussen (second from left) talks to a UC Davis class in the apiary of the Harry H. Laidlaw Jr. Honey Bee Research Facility. Third from left is forensic entomologist Robert Kimsey, one of the two class instructors.(Photo by Kathy Keatley Garvey)
Extension apiculturist Eric Mussen (second from left) talks to a UC Davis class in the apiary of the Harry H. Laidlaw Jr. Honey Bee Research Facility. Third from left is forensic entomologist Robert Kimsey, one of the two class instructors.(Photo by Kathy Keatley Garvey)

Extension apiculturist Eric Mussen (second from left) talks to a UC Davis class in the apiary of the Harry H. Laidlaw Jr. Honey Bee Research Facility. Third from left is forensic entomologist Robert Kimsey, one of the two class instructors.(Photo by Kathy Keatley Garvey)

Extension apiculturist Eric Mussen shows a frame to the students. (Photo by Kathy Keatley Garvey)
Extension apiculturist Eric Mussen shows a frame to the students. (Photo by Kathy Keatley Garvey)

Extension apiculturist Eric Mussen shows a frame to the students. (Photo by Kathy Keatley Garvey)

Varroa mites are reddish brown. (Photo by Kathy Keatley Garvey)
Varroa mites are reddish brown. (Photo by Kathy Keatley Garvey)

Varroa mites are reddish brown. (Photo by Kathy Keatley Garvey)

Extension apiculturist Eric Mussen reaches for a smoker as a bee (far left) buzzes off. (Photo by Kathy Keatley Garvey)
Extension apiculturist Eric Mussen reaches for a smoker as a bee (far left) buzzes off. (Photo by Kathy Keatley Garvey)

Extension apiculturist Eric Mussen reaches for a smoker as a bee (far left) buzzes off. (Photo by Kathy Keatley Garvey)

Posted on Wednesday, April 16, 2014 at 5:18 PM

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