Review of Bee Health

Local orchard farmers may be feeling the sting of a decreased honeybee population when it comes time to pollinate their cherry fields in the coming weeks.

“I’m concerned about it,” said Peter Van Dyke, President of Van Dyke Organics in Gilroy, which has just less than 20 acres used for cherries. “Bees are real important for growing cherries.”

Ralph Santos, owner of Ralph’s Cherry Hut in Gilroy, has more of a wait-and-see attitude.

“It’s a concern, but not until we get to that time when we need the bees,” said Santos, who takes care of about 225-250 acres in Gilroy as well as a large block in Morgan Hill. “If the weather stays warm and the almonds get out of the way, we get a better chance to have bees more readily available.”

Cherry pollination usually begins in mid- to late March and the harvesting follows at the end of June. Almond pollination starts in late February. However, local beekeeper Dan Carroll said more and more cherry growers spray their orchards to encourage early bloom on the pollination process, so they can beat out the Washington cherry harvest.

“It always gets done, but it’s always a scramble and a nail-biter to get through the season,” said Carroll, proprietor of Bonnie Bee Farms in Morgan Hill. “Is there going to be enough to (pollinate) the almonds? Not enough to do a good job. Is there going to be enough to do the cherries? Well, cherries have always been a problem.”

Carroll, who keeps his bees in Morgan Hill and grows almonds in Gustine in the Central Valley, once had 1,500 hives on his farm, but is down to 700 hives, which he has maintained for the last few years. He uses his own bees to pollinate his almonds and helps out a few neighbors in Gustine before transporting the hives to the cherry fields in Morgan Hill and Gilroy.

“Almonds are much more lucrative than cherries for a beekeeper,” Carroll said because there are fewer bees in the winter, so the price goes way up.

“The bees have not started rooting up and making babies that early in the year and we want hives with a lot of bees in there,” he explained.

While an apiarist may get between $150-200 per hive to pollinate a farmer’s almond crop, as the season extends and the bees multiply, it drops to $25-30 per hive for cherries. But as the bee population dwindles and the demand continues to rise with the expanding almond acreage, the cost to farmers also goes up.

That dwindling bee population is an ongoing concern.

“I’m running at about 40 percent loss this winter, which is better than last year, which was about 60 percent,” said local apiarist Wayne Pitts, owner of Uvas Gold Apiaries which has colonies from Gilroy to Woodside to Aromas. “I never count the number of hives I have. But the ones I’ve visited recently, four of 10 hives are dead.”

Pitts blames the parasitic mite, called a Varroa mite for the depletion of bees. Varroa mites feed off the bodily fluids of adult, pupal and larval honeybees, and may carry viruses that are particularly damaging to the bees, and accordingly they have been implicated in Colony Collapse Disorder (CCD). The Varroa destructor is an external parasitic mite that attacks the honeybees and causes the disease varroatosis.

“They don’t kill the bees directly,” Pitts explained. The mite actually reproduces within the honeybee colony by attaching to the body of the bee and weakens it by sucking hemolymph from its host. If the infestation is not treated correctly and continues to spread, it causes birth defects in the bees and leads to the death of a honeybee colony.

“You can’t get rid of mites. You have to control them,” said Pitts, who also has been president of the Gilroy Beekeepers Association since 1998. “Genetically, you’ll have bees that survive mites.”

Pitts currently treats his hives with Mitacide, but “you have to change every two years or you build resistant mites.” Pitts will convene on April 1 with his fellow beekeepers as they embark on a Survivor Queen Rearing Project, which takes the bees that have survived two winters and mate them “because the odds are greater that their offspring will survive.”

“We’re going to make queens from those survivor bees to see if we can pass them survivor traits,” Pitts explained. “Eventually the bees and mites will get in balance with one another.”

Paula Joiner, who recently started the Paradise Blueberry Company in Morgan Hill, has purchased Russian bees instead of more commonly used Italian bees to combat the Varroa mite infestation. She said Russian bees can better fight off the parasite because they’ve been exposed to it for more than 100 years.

“I do believe the Varroa mite is the main cause,” said Joiner, who currently works with only one hive but hopes to increase to 10-15 by next year. She went on to say that another problem is when commercial beekeepers expose their bees to different pesticides while transporting their hives across the country.

Apiculturist Eric Mussen, who joined the UC Davis Department of Entomology in 1976 and is widely sought for his expertise on Colony Collapse Disorder, honeybee nutrition, diseases, pesticides, crop pollination and beekeeping, believes it is more than just the destructive parasite to blame for the decreased numbers in bees.

“Last year was among, if not the, worst year for honey production across the country,” said Mussen. “If the nectar sources are not there, then the pollen sources are not there.”

Honeybees require about 50 pounds of mixed pollens (and 100 pounds of honey) a year to produce all the bees that cycle through the season, Mussen continued. When they can’t find that food, the bees become malnourished. In that condition, they become susceptible to infections and have reduced ability to tolerate parasites and toxic substances in their environment.

Joe Traynor, a pollination broker for California Scientific Ag Company, lines up bees for almond growers from Bakersfield to Turlock. His company inspects the colonies to make sure they are strong enough to properly pollinate large acres of almonds.

“Even though the bee colonies are weaker than normal, they should get the job done with the good weather,” said Traynor, who has gotten more calls from growers heading into this season than any other year. “I haven’t been able to fill all the orders. I just can’t come up with the bees. This is the first time I haven’t been able to come up with the bees.”

Other factors for the weakening of bee colonies as well as reduction in the bee population include a lack of forage and natural habitat for the bees to feed off, the use of pesticides on crops and more commercial farming.

“My feelings personally are I think it has a lot to do with pesticides,” said Van Dyke, who brings in between 100-150 hives to pollinate his cherry crop. “My beekeepers that come out to pollinate, they winter their bees here. The bees can come here and forage and thrive.”