Varroa

Have you checked your varroa drop recently? I just checked and found 2 per day (first week of February). Unlike previous years I did not use oxalic acid, it obviously harms (annoys) the bees so I am watching to see how the colony handles the mites on its own this year.

2 per day is not enormously meaningful in winter, but it is always worth recording such things when one has the time to, as you never know what will be significant when you look back in your notes. If you’re wondering what’s “average” in the UK, the closest dataset I can find to compare with is here, though this is the weekly drop not daily, and it’s during treatment with oxalic acid which will, of course, knock out many mites.

 ~ ~ ~ ~ ~

You may be aware that FERA have just reviewed the UK’s honeybee health strategy and asked for feedback here before finalising their report. On reading these documents I was struck that their varroa management policy was along these lines: the varroa mite rapidly evolves resistance to every miticide developed. The solution is… training beekeepers in a code of practice and “treatments”. I understand this to mean an emphasis on developing and using miticides, implying they are concerned that many honey-centric beeks do not consider the wellbeing of their bees and just desire a “recipe” to follow. The idea of developing varroa resistant strains of honeybee is dismissed out of hand even though they make a point that rapidly-breeding invertebrates (mites) evolve rapidly when put under stress. So I did some research on the Web and sent as concise a response as I could, strongly suggesting the National Bee Unit set up a breeding program. I encourage you to do so too, but I’ll let you word your own emails. (Politicians must detest those mass-copied “letters” from armchair activists too lazy to express their own thoughts but eager to jump on fashionable bandwagons.) Anyone sceptical of the possibility of varroa tolerant bees should pause and consider how, then, the Asian bee Apis Cerana -the original host – survives?

It must be emphasized that miticides will be vital for some time. Few beekeepers can afford to let [typically] 95% of their colonies collapse and breed from the survivors (known as the Bond, i.e. Live And Let Die, strategy). This will ruin commercial honey producers and I am taking a big chance with my remaining colony. But, in the long term, genetic variability is the only practical solution.

If you’re interested in varroa resistant bees, here are some starting points:

  • An excellent broad ranging, non technical page on breeding for varroa tolerance is here. One issue he raises is, it’s all very well breeding varroa tolerant queens but if the area is flooded with useless drones from neighbours’ hives…! However, he’s a conventional beekeeper, and for natural beekeepers this is eventually less of a problem because we have more of our own drones flooding the area (because we don’t suppress drone production like conventional beeks). So after a few generations our colonies’ genes have an edge. Ironically some conventional beeks regard our masses of untreated drones as a reservoir of varroa infection, rather than a pool of resistant genes.
  • Key search terms are “VSH” and “SMR” (Varroa Sensitive Hygiene and “Suppression of Mite Reproduction”).
  • Russian bees -a highly tolerant strain of European honeybee whose range overlaps with the Asian bee, and is already highly resistant to varroa.
Advertisements
This entry was posted in Ecology, Inspections, Pesticides. Bookmark the permalink.

One Response to Varroa

  1. I’m researching the use of Homeopathic remedies in beekeeping – specifically for the treatement of Varroa and Nosema. I’ve collected several cases so far where certain remedies strengthened the bees resistance sufficiently to cleare the hive of Varroa. Other remedies are then used to help the bees recover from the weakening effects of the mite. Early days yet but I’d be keen to share information with those interested in trying it out in practice. If this sounds of interest then please get in touch.

    Like

Leave a comment ...

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s