Varroa resistant bees in Norway

It is positive that the research community is becoming increasingly focused on varro-resistant honeybees. The latest report comes from a doctoral student, Melissa Oddie. She has started an investigation why a Norwegian beekeeper’s population of bee colonies can be called resistant because, according to his information, he hasn’t treated his bees against varroa in at least 19 years. Their article is a pre-presentation before it is peer reviewed. It could be read and downloaded here when I was writing this: https://peerj.com/preprints/2976.pdf

The result showed that the varroa population of the test bees had a growth rate of 0.87, ie a decrease over time. While the non-resistant control colonies had a growth rate of 1.24, i.e. an increase of the mite population over time.

 

Positive details in the study

  1. One of the beekeeper’s own apiaries was used and its colonies were used in the test.. Thus, no queen was introduced to other types of bees in another place. The resistant bees and their queens were tested in their normal environment.
  2. The distance between the test and the control colonies were big, 60 km.

 

Details missing

  1. The name of the beekeeper. He had earned a place among the authors.
  2. The beekeeper has exchanged breeding material with another commercial beekeeper since 2004. This beekeeper has also not been treating his bees for many years.
  3. The number of bee colonies forming the resistant colony population is not mentioned.
  4. The cell size used by the beekeeper is 4.9 mm, ie small cellsize, for almost as many years as he did not treat against varroa.
  5. The cell size of the control colonies is also not mentioned. Is it also 4.9 mm or larger?
  6. It is not mentioned if there are other bees close to the test and control colonies. The test beekeeper has several apiaries. If any of them are near the test apiary, it would probably not affect the test. How many other type of bees could be found near the test and control apiaries (if any) is not mentioned and, if so, the distance to these bees. It is important for the reinvasion risk.
  7. Nothing is mentioned of annual losses for the years backwards for the test and control colonies. It may be of secondary significance and these figures may also not have been secured. However, some kind of data about of the losses at the beginning of the adaptation of the test bees could have been interesting to take part of. But the article is inspiring anyhow.
  8. There are also no tips for beekeepers inspired by their article to start developing their bees to become resistant. Of course, it is not a task of the test I understand, but some kind of comment about this has been positive since many beekeepers will certainly appreciate the article and be inspired by it. However, such advice I look forward to find in follow-up articles in bee magazines.