California almond growers have always relied heavily on honeybee hive rentals to pollinate their orchards. Responsible for 80% of global almond production, these growers are highly dependent on obtaining healthy honeybee colonies from contracted commercial beekeepers.
With a record 1 million almond-bearing acres forecasted for this year’s harvest, meeting the growing pollination demands of the industry may become increasingly more difficult for migratory beekeepers. On average, they have sustained annual losses of one-third of their hives each winter and struggle to mitigate challenges associated with mite pressure, pathogen transmission, pesticide exposure, and nutritional limitation.
Since its inception in 2012, researchers associated with the Integrated Crop Pollination (ICP) project, funded by a five-year USDA Specialty Crop Research Initiative grant, have been working towards identifying management practices that can provide improved support for almond pollination in California. In particular, they are investigating the use of an alternative bee, the blue orchard bee (BOB), to assist honeybees with meeting the intense the pollination demands during almond bloom.
The BOB is a commercially available cavity-nesting bee that preferentially forages on spring-blooming orchard crops. Unlike honey bees, BOBs are not social and do not live in a hive or make honey. They are a solitary species, in which each female mates and forages for provisions for her offspring alone.
They have one generation per year, and are free-flying adults for only a few weeks of that year. Most of their life is spent as adults in individual cocoons. This is also known as diapause, which is essentially an insect hibernation.
BOBs’ Pros and Cons
BOBs are a popular pollination choice for many orchard producers and have been implemented successfully in almond, apple, cherry, and pear orchards. Part of what makes them appealing for so many cropping systems is their activity can be carefully timed to align with bloom by manipulating standardized storage incubation practices.
ICP researchers think BOBs could offset potential shortages of hives in meeting future pollination needs. In fact, previous research has shown when BOBs co-pollinate orchards with honeybees, growers see significantly improved…