Spring Bee Losses — A Reminder to Follow Best Practices and Improve Communication

August 1, 2014

The California Department of Pesticide Regulation (DPR) and U.S. EPA are investigating losses of adult and immature bees rented for almond pollination that were observed and reported this spring. There are a number of factors at play, and while the facts aren’t all in, two patterns have emerged.Communication between the grower and beekeeper regarding bloom-time pesticide practices and applications is essential to protect the health and safety of honey bees. Photo courtesy of Project Apis m.

First, losses appear to have occurred in almonds as a result of tank-mixing insecticides with bloom fungicides. Based on new information, the Almond Board of California (ABC) has recommended avoiding insecticide applications during bloom since 2013. A number of insecticides are registered as safe to bees on the basis of low adult toxicity; however, recent information indicates some may be harmful, particularly to young developing bees in the hive.

Second, bee losses appear to have occurred as a result of bee exposure to chemicals applied in other crops planted in the vicinity of almonds; this was particularly the case after almond bloom was over and pollination completed.

The tank mixes of insecticides with fungicides applied in almonds and associated with bee losses were not a label violation. The EPA and DPR are evaluating information with an eye toward including warnings on product labels when justified, but this will take some time.

In the interim, the Almond Board of California, beekeepers, the University of California and California regulatory officials are diligently working collaboratively to provide information on best management practices in relation to pesticide application to all the groups and audiences involved.

Regardless, heading into the 2015 pollination season, it is extremely important to remind almond growers that when making pesticide applications at bloom to continue to follow ABC’s best management practices:

  • Avoid applications of insecticides during bloom until more is known about the impact on bees; and
  • Minimize exposure of bees and pollen to fungicides by avoiding applications when pollen is available and bees are foraging; spray only after mid-afternoon and at night.

In addition to the above, more must be done to strengthen the chain of communication about bloom-time pesticide practices and applications among all parties involved in pollinating almonds and/or applying pesticides to orchards. Prior to bloom, all parties should agree on products that can be applied in the orchard and the methods and timing of application. During bloom, additional communication is necessary on products, methods, timing and target area of spray applications to be made.

Communication should start with the contract between grower and beekeeper, and be maintained all the way through the chain. In larger operations, communicating along this chain can be extensive and include beekeeper-broker-owner-farm manager-pest control adviser-applicator.

A second area of attention should be aimed at minimizing almond post-bloom losses resulting from bee exposure to chemicals applied in other crops. Once almond pollination is done, bees placed in almonds are at risk to pesticide exposures in other crops because they extend their foraging range well beyond almonds. Communicating with the beekeeper/broker the guidelines for when almond pollination is complete and hives can be picked up will be key to minimizing these losses. In future articles, the Almond Board will be reviewing these guidelines as well as other pollination and bee health best practices.

The Almond Board is committed to bee health and its partnership with beekeepers. A key goal is to ensure almond orchards continue to be, based on research and our efforts, a good, safe place for honey bees to forage — a place that keeps them healthy and where hives increase in size.