What is it: VSH is a trait that is expressed in honey bees where they will remove the varroa destructor mite infested cells from the brood nest. It is a physical and natural way for a hive to control mite populations. This enables the hive to thrive throughout the honey production season keeping mites in check and allowing chemical treatments to be deferred until after your supers have been removed.
How does it work: In hives with VSH expression cells that have been capped for 4-6 days and reproductive mites are present are chewed open and the mite infested pupae are removed. This kills the immature mites and interrupts the mite reproductive cycle. In the image below bees are removing a mite infested pupae:
Why is it Important: The varroa destructor mite since introduction has decimated honey bees in north america. The mites feed on the fat of the bee and introduce a list of viruses that weaken the health of the hive making it hard of them to thrive and survive winters.
How do I add VSH genetics to my apiary: VSH genetics are additive meaning they can be introduced into any bee yard. The best way to do this is to buy an instrumentally inseminated VSH breeder queen, but these start at $300. However, hybrid VSH bees (e.g. VSH queens open mated to non-resistant drones) also have significant resistance to varroa mites. This means an open mated queen from a VSH breeder queen will express up to 66% of the VSH genetics and will express mite resistance. If you are on a tight budget or want to try a VSH queen with some risk you can purchase a VSH virgin queen.
It’s very important to be selective when ordering queens. Most queens are produced in warm climate states where Varroa mites can put strain on a hive but the warmer climates allow the bees to carry a heavier mite load through their cooler months. When purchasing a queen find one from a local queen supplier that is grafting from stock that has survived the winter and ideally have VSH expression.
Our VSH Queens are available here:
Queens – American Heritage Apiary
Results: Jason Bragg at New River Honey bees has run tests where he starts 2 packages of bees. One with the package queen and one with one of his open mated VSH queens. When doing a VSH test the package queen had 5 reproductive mite colonies whereas the hive with the VSH queen had 1. Each of the 5 reproductive had 3 daughters which would lead to 15 with each hatching 3 more, etc.
Planned Testing: We plan on doing a similar test but with 5 packages and their queen, 5 of our open mated VSH queens, and then our 100% VSH breeder queens. We will be providing monthly VSH checks via a mite wash test and possibly looking at 100 worker cells for reproductive mite colonies.