Posts Tagged: Bee Briefs
Extension apiculturist Eric Mussen of the Department of Entomology, University of California, Davis, writes an interesting bimonthly newsletter.
He's been writing from the UC Apiaries since he joined the department's faculty in 1976.
Never missed an edition. Not one. And his newsletters are eagerly awaited.
His newsletters and Bee Briefs are available online for free downloading. Or, folks can subscribe for free.
In the current edition of from the UC Apiaries, Mussen explores an article in Catch the Buzz about statistics released by the Apiary Inspectors of America (AIA) that show startling winter bee losses.
AIA and the USDA honey bee lab in Beltsville, MD, reported on losses from data collected for 22.4% of the country's 2.46 million colonies, Mussen said.
"We lost about 33.8% of those managed colonies," he wrote. "Similar to previous surveys results, 28% of the beekeepers stated that they found some totally empty hives reminiscent of colony collapse disorder (CCD).
"Beekeepers reported the following reasons for colony losses: starvation, 32%; weather, 29%; fall weakness, 14%; mites, 12%; poor queens, 10%; and CCD, 5% (Yes, that is 102% of the losses)."
"What caught my eye was the 32% starvation. Beekeepers usually do a pretty good job of paying attention to how much food is stored in the hives, and it is difficult to believe that they would allow a third of their colonies to die of starvation.
"Normally, it is pretty easy to determine when a colony has starved. The food, especially honey, is all gone and there are dead bees stuck head-first in the empty cells in the combs. Even to the uninitiated, it is obvious that the bees ran out of food and died."
But why did they die? You'll want to read his comments.
To a beekeeper, it's a four-letter word.
Specifically, the varroa mite, also known as Varroa destructor.
It's a small (think flea-sized) crab-shaped parasite that feeds on bees, either in the brood (immature bees) or on adult bees.
Extension apiculturist Eric Mussen, member of the UC Davis Department of Entomology faculty, just updated his Bee Brief on this blood sucker. His Bee Briefs, all posted online on the department Web site, can be downloaded for free.
This Bee Brief is titled "Treating Colonies for Varroa Mite Infestations." (You'll also want to read his updated colony collapse disorder (CCD) Bee Brief.)
It's apparent, Mussen says, that resistant mites are now prevalent in the United States, including California.
"Chemical testing has demonstrated that varroa mites commonly are resistant to fluvalinate, coumaphos and amitraz. Losses of wintering colonies were over twice as high as 'normal' during the early 2000s, with one of the worst losses (40 to 60 percent) of California (and total U.S.) commercial colonies over the 2005-05 winter. Infested colonies dwindled away during the fall and winter."
Meanwhile, a hive without a varroa mite is a scarcity indeed.
You can see varroa mites on the larva (below) and on an adult bee.
Just think if you had a blood sucker on you like that.
Mite on Pupa