- Author: Kathy Keatley Garvey
If you have a bee hive, you most likely have mites.
Varroa mites, those blood-sucking parasites that latch onto the brood and also thrive on the adult bees, can weaken and destroy a hive.
Extension apiculturist Eric Mussen, member of the UC Davis Department of Entomology faculty, frequently fields calls about varroa mites.
In his latest edition of from the UC apiaries, he points out that "obtaining fumigants for varroa mite control may be somewhat difficult at this time for beekeepers."
"I haven't checked on the Apiguard® situation recently, but shipments from Europe had been held up, apparently by U.S. customs," Mussen wrote. "The other desired fumigant, Mite Away II pads, are vanishing from the market quickly. They are out of production and soon will not be available. The reason behind this is because NOD Apiary Products, in Canada, has decided to stop producing the pads and instead offer a formic acid product in strip form."
Today we spotted a varroa mite on a foraging bee. The bee, a golden Italian, was nectaring lavender.
Unfortunately, a nasty little parasite was eating at her.
- Author: Kathy Keatley Garvey
What's wrong with this photo?
A honey bee is nectaring a lavender, right?
Right.
But if you look closely, you'll see a Varroa mite--a parasite--attached to her.
Varroa mites, considered the No. 1 pest in the honey bee industry, are linked to colony collapse disorder, a mysterious phenomenon characterized by adult bees abandoning the hive, leaving behind food stores and the brood.
Varroa mites are so common that it's rare to find a hive without them.
Female mites reproduce inside brood cells in the hive. Mites suck the bee blood or hemolymph; in doing so, they spread viruses, stunt the growth and cause deformities.
Within two years, they can destroy a colony.
Not a pleasant sight.
- Author: Kathy Keatley Garvey
It's not a pretty sight--the Varroa mite attacking a honey bee.
Beekeepers are accustomed to seeing the reddish-brown, eight-legged parasite (aka "blood sucker") in their hives.
UC Davis bee breeder-geneticist Susan Cobey, manager of the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road, is among those who've declared war on the mites.
She's carrying out an intensive and comprehensive breeding and selection program aimed at developing honey bees that are resistant to pests and diseases.
The Varroa mite is a serious pest of honey bees worldwide, spreads diseases, and can weaken and destroy the colony. It is no doubt one of the culprits involved in colony collapse disorder, a mysterious phenomenon characterized by honey bees abandoning the hive.
Here's what the Varroa mite looks like attacking an immature bee.
- Author: Kathy Keatley Garvey
The BBC this week examined colony collapse disorder (CCD), a mysterious phenomonen characterized by bees abandoning their hives. The adult bees buzz off, leaving the brood and stored food behind. They do not return.
Many bee specialists believe it's not just one thing causing CCD--it's a combination of factors or a "perfect storm": parasites, pesticides, malnutrition, stress, diseases and global weather changes.
The blood-sucking varroa mite, a parasite of honey bees, is a contributing factor in the decline of bee health.
When the BBC interviewed Cooperative Exension Apiculturist Eric Mussen of the UC Davis Entomology Department faculty about varroa mites, he said that the European or western honey bee doesn't "do a good job" of removing them. To a human, the varroa mite would be about the size of a softball "running around on you."
The varroa mite, Mussen said, is problematic because of three things:
1. It sucks the so-called bee blood, making the bee nutritionally weaker
2. It interferes with the immune system
3. The varroa can get viruses on its mouthparts so it inoculates bees with viruses as it travels from one bee to another.
Listen to Mussen talk about the varroa mite as he examines it under a microscope. Then imagine a softball-sized bloodsucker on you.
- Author: Kathy Keatley Garvey
The varroa mite (see photo below) is an external parasite that attacks honey bees. It sucks blood from the adults (apparently preferring drones, the male bees) and from the brood (immature bees). "It's commonly found in most hives," says UC Davis apiculturist Eric Mussen.
Untreated infestations of varroa mites can weaken and kill honeybee colonies
Initially from Asia, the eight-legged reddish brown parasite was first detected in the United States in 1987. It was discovered in two states that year: Florida and Wisconsin (from the same beekeeper colonies). It's now all over the United States.
"Bees try to brush it off with their legs," Mussen said.
Mussen, editor of the bi-monthly newsletter, "from the UC Apiaries," writes about varroa mites in his July-August edition. He's been writing the newsletter since 1976.
You can read the current editions online. You can also subscribe by e-mail or by snail mail. See instructions. Or contact Mussen at ecmussen@ucdavis.edu for more information.
In addition to the UC Apiaries newsletter, Mussen writes Bee Briefs, where you can read about such topics as "getting started in beekeeping," "removing swarms" and "honey bees and California native plants."
Both publications are invaluable to the beekeeping world and to folks who just want to know more about bees.
Mussen, a Cooperative Extension apiculturist at UC Davis for more 31 years, is the 2008 recipient of the Distinguished Achievement Award in Extension from the Pacific Branch of the Entomological Society of America.
In national demand for his expertise on honey bees, Mussen appeared on Good Morning America on March 12, and has also been interviewed for The Lehrer Hour, New York Times, Los Angeles Times, and the television documentary, California Heartland. Coverage also includes Sticky Stuff of Modern Marvels, the History Channel.
“Eric is the primary conduit of information on apiculture, certainly for the entire western U.S. and perhaps even broader than that,” said UC Davis entomologist Larry Godfrey, past president of the Pacific Branch of ESA.
Widely recognized for his work, Mussen received the California State Beekeepers' Association's Distinguished Service Award in 1999; Apiary Inspectors of America's Exceptional Service Award in 2000, and the California State Beekeeper Association's Beekeeper of the Year Award in 2006.
In 2007, the American Association of Professional Apiculturists honored him with an Award of Excellence in Extension Apiculture, one of only five awards the group has presented in 20 years.