SAVE THE BEES
Most people have heard that honey bees are dying at an alarming rate. According to the Bee Informed Partnership, the annual colony losses for the past two years have been over 40%. There are many stressors that are causing the deaths: from pesticide use, reduced forage, and increased diseases. Some of the most deadly diseases are spread by a small mite called Varroa Destructor.
Varroa mites originated on the Asian Honey Bee (apis cerana) and jumped to the European Honey Bee (apis mellifera) in the 1960s. In the 80s, Varroa had made its way to the United States and is currently in all 50 states. Varroa to bees is much like a tick on humans. The Varroa mite doesn’t directly kill bees, but is a vector for deadly viruses such as Deformed Wing Virus. Since their introduction, we have found many chemicals to kill the mites such as pesticides and organic acids. The problem is that prolonged use of most treatments leads to resistance. Most people will agree that the best long term solution is to have the bees manage mites themselves.
There are several research laboratories that are actively breading bees to control varroa in the hive. From a genetics standpoint, the queen is the key. The queen is the only member of the hive that produces offspring. When a queen matures she will go on a series of flights to mate with 10 to 20 males (drones). She will store the semen from these mating flights in an internal organ called a spermatheca. All the workers in the hive will be a combination of her genetics and one 10 to 15 drones. The drones produced will only contain the queen’s genes.
For bees in the wild to thrive, they need to raise brood (new bees), collect food, and remain healthy. When Varroa hit the United States in the 80s, most of the feral hives died. The hives that survived had some natural ability to combat Varroa. Bees naturally select the traits that allow them to survive and reproduce. The more times colonies reproduce, the more selective pressure that can occur. Managed honey bee hives have the same issue. If the percentage of mites / bees increases, the hive is almost guaranteed to die. The process is not fast. In the spring, the bees are rapidly increasing their population in the hive. The varroa is also increasing, but since they reproduce in the bee’s brood, their population lags behind the bees. Most locations in the country will have a period of time where they decrease due to diminished food supplies or cold weather. At this point the bee population decreases but the mite population continues to increase. This is the point where the hives will succumb to the increased mite/virus load and die. In our location, the buildup starts in February and die off normally happens in September or October. This gives you about one generation per year of natural selective pressure.
At Pirate Creek Bees, our breeding program focuses on three selection criteria: varroa resistance, resource production, and gentleness. We select for gentleness so that the bees don’t become a hazard or nuisance to humans. Resource production ensures the bees produce enough honey and pollen to survive and provide excess honey for us. Selecting for Varroa resistance helps the bees cope with mites without human intervention. We select queens for breeding that best meets our selection criteria. We also select drones that meet the same criteria. Our primary mating location is in a deep, walled valley where we can saturate the drone populations at both ends. This gives us a higher possibility that our queens will mate with drones with desirable traits.
This year we are increasing the selective pressure we place on the queens. Our standard hive inspect will include a varroa test- we will treat any hives that are not managing mites with organic acids. We will also replace the queen resetting the genetics within a month. This method gives us two to three times the selective pressure. Hives that don’t require treatment will be used for breeder queens and drone hives.
Our goal at Pirate Creek Bees is to increase the honey bee survival rate without human intervention. We see this as a long term management practice that can help both managed and unmanaged hives. We are also working with the Alameda County Beekeepers Association to extend this practice.