Posts Tagged: Eric Mussen
'Killer Bees': Where Are They in California?

Hollywood movie refer to them as "killer bees." Ditto, the news media.
"The known natural distribution of Africanized honey bees (AHB) in California is along a line that runs diagonally from northeastern Tulare County to southwestern San Luis Obispo County, then south to Mexico," says Extension apiculturist Eric Mussen of the UC Davis Department of Entomology. "A colony of AHB was found in Madera County following almond pollination, and the agricultural commissioner decided to call the county colonized instead of participating in a delimiting survey. However, beekeepers in Fresno County are just beginning to report encountering a few more considerably defensive colonies than they used to."
"In southern California, where AHB has been since 1994, they have pretty well filled the basin," Mussen reports. "The last time tests on feral (not human-kept) honey bee colonies and swarms were conducted, AHB were determined to be a little over 80 percent of the totals. That still may be the case with feral bees in that area, although one would expect a bit lessening of defensive behavior over time, as has happened in Brazil."
But, as Mussen points out, "it took 40 years to reach the point that AHB are not too problematic in Brazil. We have had them in California only 18 years."
“There’s no way to tell if honey bees are Africanized without DNA testing,” says Mussen, who writes from the UC Apiaries and Bee Briefs on the UC Davis Department of Entomology website. “They look about the same as the European honey bee. They tend to be a little darker than European honey bees and a little smaller. What sets them apart is their intensive defensive behavior. They’ve been known to chase their victims a quarter of a mile.”
When beekeepers find intensive defensive behavior in their hives, they kill the queen bee and “requeen” the colony. “Over four to six weeks, the original workers die of old age and the new queen replaces them with more daughters,” Mussen said.
Africanized honey bees are the result of attempts to hybridize European honey bees (Apis mellifera) with an African race. Researchers brought Tanzanian queen bees (Apis mellifera scutella) to Brazil in the 1950s. In 1957, some of the African bee descendants escaped from the researchers and beekeepers and began progressing north.
The descendants reached southern Texas in 1990 and southern California in 1994. “In California, they were first found “just outside of Blythe, in Riverside County,” Mussen recalls.
“As an area becomes colonized, the Africanized bees will show their true colors—they will exhibit their intense defensive behavior,” says Mussen, an Extension apiculturist since 1976,
Mussen recommends that anyone working or relaxing in areas known to be colonized by
Africanized bees “take precautions” by avoiding nesting areas. If the bees start to sting, cover your face with a shirt as you run for a building, vehicle or other shelter, he says. You can also carry an Army surplus gnat/mosquito veil with you to protect your face.
The honey bees’ pheromone, resembling the scent of a banana, sounds the alarm, alerting other bees to attack.
Beekeepers who collect swarms in colonized counties have a “high probability” of hiving an Africanized honey bee colony, Mussen points out, and should always look for unacceptable defensive behavior.
His advice: "It still is not a good idea to collect swarms in southern California and hive them in high human population areas."
“Africanized honey bees are not something to be feared,” Mussen said, “but they are to be respected.”
(Note: Click on this USDA map to see where the Africanized bees are now.)

Just by looking at this feral colony, you cannot tell Africanized bees from European honey bees (EHB). (Photo by Kathy Keatley Garvey)

If this cluster were in southern California, these could be Africanized bees. (Photo by Kathy Keatley Garvey)
Tough Time for Bees

He sounded the alarm.
“We need 1.6 million colonies, or two colonies per acre, and California has only about 500,000 colonies that can be used for that purpose,” said Mussen in a news release we posted Feb. 8 on the Department of Entomology website. “We need to bring in a million more colonies but due to the winter losses, we may not have enough bees.”
Those winter losses--still being tabulated--and the resulting fewer bees per hive could spell trouble for almond growers, he said.
He said 2012 was a bad year for bee nutrition.
“Last year was not a good year for honey production in the United States,” Mussen said, “and it could be one of the worst honey production years in the history of nation, although it’s been pretty rough in some of the previous years. Usually when we’re short of nectar, we’re short on pollen, and honey bees need both. So, 2012 was a bad year for bee nutrition.”
The winter of 2012-2013, in general, was bad for bees. In fact, it's never been good since the winter of 2006 with the onset of colony collapse disorder, a mysterious malady characterized by adult bees abandoning the hive, leaving behind the queen bee, brood and food stores.
Bee scientists think CCD is caused by a multitude of factors, includes, pests, pesticides, parasites, diseases, malnutrition and stress. On the average, beekeepers report they're losing one-third of their bees a year.
“We don’t know how many more bees will be lost over the winter,” Mussen told us on Feb. 8. “We consider the winter ending when the weather warms up and the pollen is being brought into the hives.”
“Many, many colonies are not going to make it through the winter. We won’t have as large a bee population as in the past.”
Mussen, a member of the UC Davis Department of Entomology since 1976, knows honey bees. He is a honey bee guru, a global expert on bees. "Have a question about bees? Ask Eric Mussen." This month, especially, he is in great demand as a news source.
The New York Times quoted Mussen in its March 28th article, "Mystery Malady Kills More Bees, Heightening Worry on Farms."
Eric Mussen, an apiculturist at the University of California, Davis, said analysts had documented about 150 chemical residues in pollen and wax gathered from beehives.
"Where do you start?" Dr. Mussen said. "When you have all these chemicals at a sublethal leel how do they react with each other? What are the consequences?"
Experts say nobody knows.
Meanwhile, Mussen spent much of the day today granting news media interviews. On Tuesday, April 2, it will be for Dan Rather Reports: Buzzkill.
It was not so long ago that honey bees drew little attention, despite the fact that they pollinate about one-third of the food we eat. A three-letter acronym, CCD, changed all that.
Rich Schubert, a beekeeper in the Winters/Vacaville area, said it best during a question-and-answer session at Mussen's UC Davis Distinguished Seminar on Oct. 9, 2007.
If 5600 dead cows were found in a pasture, instead of 5600 dead bees, people would start paying attention, Schubert told the crowd.
So true. And now they are.

Honey bee foraging on almond blossom. (Photo by Kathy Keatley Garvey)

Close-up of honey bee on an almond blossom. (Photo by Kathy Keatley Garvey)
Troubling Bee Shortage in Almond Orchards

Honey bee guru Eric Mussen, Extension apiculturist with the UC Davis Department of Entomology, said today that almond growers may not have enough bees to pollinate this year's crop of 800,000 acres.
“We need 1.6 million colonies, or two colonies per acre, and California has only about 500,000 colonies that can be used for that purpose,” he said. “We need to bring in a million more colonies, but due to the winter losses, we may not have enough bees.”
Those winter losses--still being tabulated--and the resulting fewer bees per hive could spell trouble for almond growers, he said.
The fact is 2012 was a bad year for bee nutrition. Honey production appears to be way down, maybe the worst ever in our nation's history. Nectar and pollen foraging are closely linked, Mussen says, and malnutrition is one of the stressors of colony collapse disorder (CCD), which since 2006 has decimated about a third of our nation's bees.
Bee scientists believe that CCD--characterized by adult bees abandoning the hive, leaving behind the queen, brood and food stores--is caused by multiple factors, including pests, parasites, pesticides, diseases, viruses, stress, and yes, malnutrition.
“Many, many colonies are not going to make it through the winter,” said Mussen, an apiculturist in the UC Davis Department of Entomology since 1976 (and who plans to retire in June of 2014). “We won’t have as large a bee population as in the past.”
Already brokers are getting calls from beekeepers saying “I can’t fulfill the contract. I’m going to be short.” Beekeepers charge the almond growers an average of $150 per hive.
The average almond orchard in California is in full bloom around Feb. 14, but some orchards bloom earlier or later, depending on the cultivar and the weather.
It remains to be seen what will happen in the almond orchards this year. Mussen says it may all work out well in the end as “bees pollinate almonds on a community basis. The strong colonies will make up for the weak colonies. The strong colonies will clean the orchard of pollen by early afternoon and then go down the street and grab food from nearby orchards.”
Almonds are California's biggest export. This year the National Agricultural Statistics Service is forecasting a record-breaking 2.10 billion meat pounds, valued at approximately $3 billion. California grows 80 percent of the global supply of almonds, and about 70 percent of California’s crop is marketed overseas.
No bees? No almonds.

Honey bee heading toward an almond blossom. (Photo by Kathy Keatley Garvey)

Honey bee foraging on an almond blossom. (Photo by Kathy Keatley Garvey)
A Buffet for the Bees
When the honey bee meets the flowering quince, the bee is "the belle of the ball."
The winter ball.
Suddenly the flowering quince (genus Chaenomele) transforms the bleak wintery landscape into a spring ballroom of sorts. The giddy bee is a joy to see.
Around here, the ornamental flowering quince, a member of the rose family (Rosaceae), usually blooms around late January or early February. The tightly woven pink buds unfold amid the tangled, dreary limbs that still denote winter but promise spring.
When you watch the bees, sometimes you can't tell where the pollen load ends and the anthers begin.
Extension apiculturst Eric Mussen of the UC Davis Department of Entomology encourages gardeners to plant flowers that will bloom in late winter or early spring. The bees, he says, are hungry.
Indeed they are.
The flowering quince is a buffet for the bees and a feast for our eyes.

Honey bee foraging in a flowering quince. (Photo by Kathy Keatley Garvey)

An upside-down bee in the flowering quince. (Photo by Kathy Keatley Garvey)

Pollen-packing honey bee inside a flowering quince bud. (Photo by Kathy Keatley Garvey)
Bee-ing Healthy

These are terrible blood-sucking parasites that attack bees and raise havoc in the hive. They transmit a variety of diseases and can destroy a hive.
In one of his many talks last year, Extension apiculturist Eric Mussen of the UC Davis Department of Entomology pointed out that honey bee mites include the (internal) tracheal mite (Acarapis woodi), first detected in the United States in 1984, and the (external) Varroa, first discovered here in 1987.
"The tracheal mite killed half of the nation's bees in five years as it expanded across the country," he said. "It was mostly ignored in the last few years."
Then when the Varroa mite arrived, "it killed half of the remaining colonies in five years as it expanded across the country. It killed practically all feral colonies in 1995-96."
"Mite feeding lowers pupal blood protein, resulting in underweight bees, and it shortens the lifespan," Mussen said. "Mite feeding suppresses the honey bee immune system. And, mite feeding vectors RNA virus diseases of honey bees."
Varroa mites, bee scientists agree, are definitely a key factor in the mysterious malady known as colony collapse disorder (CCD). They think CCD is caused not by "a single bullet" but by a multitude of factors, including diseases, pesticides, pests, parasites, malnutrition and stress.
Mussen defines CCD as "the failure of colonies to survive to the next season," and "there's an overwhelming quantity and quality of honey bee stresses."
With CCD, the adult bees abandon the hive, leaving behind the queen, brood and food stores.
So sad. Empty-hive stories, such as this one we heard today from a Davis beekeeper are troubling: "I went to check on my bees yesterday and found the hive empty. The wood was a little mildewy, I think they absconded because hive design needs work. I saw a couple dead yellowjackets in the hive, too, but I don't know if they attacked when there were still bees there or not."
Says Mussen: "Honey bees are stressed by many things. It begins with less naturally occurring food plants. The plants lack the mixed pollens essential for honey bee nutrition."
"It continues with loss of blood and lifespan, as well as infectious inoculations, from Varroa mite parasitism; infections by exotic microbes, especially Nosema ceranae and RNA iruses; and exposure to toxic or 'made toxic' (by adjuvants) chemical residues."
"Is it any wonder that our honey bee colonies are having a hard time surviving?" Mussen asks.
You can catch up on what's troubling the bees and the scientific research under way by reading his bimonthly newsletter, from the UC apiaries, posted on the UC Davis Department of Entomology website.

This frame shows healthy bees. (Photo by Kathy Keatley Garvey)

Queen bee and her workers. A Varroa mite is on the head of a bee at right of this photo. (Photo by Kathy Keatley Garvey)

Close-up of a Varroa mite on a worker bee. (Photo by Kathy Keatley Garvey)