Apiary inspectors benefit from DPR training sessions

Seeking strategies to reduce honeybee mortalities, county apiary inspectors spent a day learning honeybee and hive handling skills and adding investigative experience at training sessions hosted by the California Department of Pesticide Regulation.

Counties are responsible for investigation of any possible pesticide use violation, or when there has been damage or harm to honeybees in their jurisdiction. Approaching and opening hives, knowing what is normal and what is not inside hives and how to collect samples were part of the hands-on training at the University of California Kearney Research and Education Center and in Modesto.

Noting that bee health and protection is a state, national and worldwide issue, Karen Francone, environmental program manager at DPR, said the training would improve investigations into bee mortality and brood loss from possible pesticide exposure.

Inspections of bee sites can be prompted by a request from a grower to certify colony strength or that colonies are free from certain diseases so they can be transported to another state. Francone said most investigations follow a report of bee and/or brood death.

A session on bee safety reminded inspectors of the importance of paying attention to bee signals when approaching hives. The bees may fly at your face or buzz overhead as a warning, said Shannon Mueller, UC Cooperative Extension farm advisor. A smoker can be used to disrupt defensive behavior, but inspectors should limit their exposure time inside hives and avoid crushing bees.

"Bees can recognize their beekeeper," said Elina Niño, UC apiculture specialist and speaker.

Niño said guard bees release alarm pheromones when they sense danger. Those alarm pheromones are also released when a honeybee stings or when bees are crushed.

These actions, she said, show that bees are not being aggressive but defensive in their behavior. That defensive behavior can vary between hives, due to genetics. Africanized bees are one example and can be a threat in hive inspections. Protective equipment is always advised, Niño said, and it should be clean, because suits worn previously may have traces of alarm pheromone.

If Africanized bees are suspected, inspectors were told to run and not swat or crush the bees.

"They can be relentless and will pursue you for longer distances," Francone warned.

Inspectors were told to approach hives from the back and not block the bees' front entrance. If a smoker is used to calm the bees, Mueller said, allow time for it to have an effect.

In a healthy colony, inspectors will find many adult worker bees, a queen, a mostly solid brood pattern with medium-brown capping that is convex and without punctures. They will also see lots of pollen and honey. Healthy eggs are one to a cell and attached to the bottom. Healthy developing pupae or brood are "c"-shaped white grubs. They are white and shiny during initial development and darken as they mature. The eyes are the first part to change color.

Colony collapse disorder has been a major concern of beekeepers and others who depend on pollination of crops, but Niño said there are multiple factors in massive bee losses and CCD is not the cause of every die-off. Loss figures in managed bees in 2014-15 were reported at 42 percent of hives. Niño said this year's numbers are not expected to be better, and she noted that colony losses were tallied from a self-survey of both commercial and backyard beekeepers.

The list of causes for bee deaths include winter starvation, weakened colonies due to disease, and pesticides. Other factors are farming practices, pathogens, pests, disease management and climate.

Varroa mites, first discovered in the U.S. in 1987, are a big deal and highly associated with colony loss, Niño said. These bee pests feed on the blood of adults and brood, reproduce in brood cells and transmit viral diseases. They are also known to suppress immune responses in bees. Niño said it is recommended that colonies be monitored monthly for mite levels, as numbers can explode and devastate hive strength.

Signs of high levels of mite infestations include scattered brood, weak bees and a lower rate of return to the colony after foraging. Inside the hives are abnormal brood patterns, sunken and chewed cappings and impaired larvae.

Other pests of honeybees include small hive beetles, mice, wax moths and ants.

Diseases can also devastate honeybee colonies, and inspectors should be careful not to spread the pathogens when they move from hive to hive. The most deadly disease is American foulbrood. Larvae become infected in very early stages of development and die just after the cell is capped. Cappings will appear sunken and punctured. Infected hives have a very distinctive odor, Niño said. Beekeepers should have an action plan if the disease is found in their hives. Burning or burying all hives and infected materials is recommended.

European foulbrood is considered more a stress-type disease that will clear up with honey flow. The fungal disease Nosema attacks the digestive system of worker bees, queens and drones, bursting cells.

Interpreting pesticide labels and communicating with beekeepers and applicators in the case of a suspected pesticide kill is a large part of a county apiary inspector's duty. Mara Johnson, environmental scientist with DPR, said some pesticide products will have advisory language for bee protection and others will have mandatory language directed to drift.

Labels on pesticide products are there to protect bees and other insect pollinators. They contain a "bee icon" and information about forage habits and routes of pesticide exposure to bees. Bees can be impacted by a pesticide through direct contact or indirectly by feeding. Nest sites or nest materials may also be affected.

(Cecilia Parsons is a reporter in Ducor. She may be contacted at ceciliaparsons8@gmail.com.)