The bees that Johnstons Honeybee Farm utilizes have been developed since 1991. We started with a Carniolian/ Italian hybrid and have been raising our own queens since then. Twice we have suffered overwintering losses of around 75% and have bred from the bees that have survived. The first loss was caused by the advent of the tracheal mite, an internal parasite of bees; the second loss was caused by advent of the external parasite, Varroa destructor. From 2003 to 2011, we did not use any pesticides to treat for Varroa. In the fall of 2011 and again in 2012, our bees were treated with Apiguard whose active ingredient is the essential oil thymol. No miticides were again used in 2013, 2014, or 2015. We do not consider Varroa to be a major problem for our bees.
Our bees are:
- Winter hardy
- Mite Resistant
We are also selecting for queens with greater longevity.
The next great challenge will be developing bees with resistance to Nosema ceranae, a fungul disease of the bee's intestines that reduces honeybee lifespans and hive productivity; this disease is probably at least partly responsible for Colony Collapse Disorder (CCD). Nosema ceranae became common in North America in 2006, the same year that CCD first appeared. We have been testing our bees for Nosema since 2012 and using this information in the process of selecting breeder queens. It is still a work in progress.
In 2013, we began testing our breeder queens for hygienic behaviour by freezing some of the brood with liquid nitrogen and observing the rate of dead brood removal. We found that some hives were much more hygienic than others. We will continue to use this method as another parameter for selecting queens from which to produce the next generation of queens.