Overall colony loss 2007-8 30.5%, 2008-9 19.2%
Varroa treatments Apiguard/Thymol (Autumn) 2007-8 41.1%, 2008-9 60.9%. Is that not an inferred correlation?
The use of Apiguard by those reporting back to the BBKA from a 'random selection of members in England' has increased, and yes, the number of colonies being lost in those reporting back has decreased, but the reason could be
anything, it's not a strong correlation, and the use of a particular treatment could quite possibly be totally irrelevant (see below)
For instance one of treatments on that list still has quite high usage levels but is widely acknowledged as having very reduced efficacy due to mite resistance, whilst another treatment on that list has, at least in the UK, very high efficacy but as yet very little reported usage.
Other factors not even reported could be significant, for instance the weather,local crops, pesticide use, foul brood from hive migration, genetic variations in the bees and a whole host of other things. As they say in the article
'in the coming weeks we will be analysing the data further to see if their is a relationship between colony survival numbers and the varroa treatments used' Personally I doubt there is enough data to enable
any statistically sound and significant conclusions to be drawn.
How about the situation where a beekeeper lost all 20 colonies over winter 2007/8 and ended up with 5 from swarms going into winter 2008/9 and now again has 20 colonies? Is that zero losses, 75% losses, 300% gain?
Or the situation where another beekeeper went into autumn last year with two colonies, they both died in spring with Nosema, they bought one colony, collected a few swarms and now has 10 colonies? 100% losses or 900% gain?
In both cases the colonies were run by different beekeepers in the same geographical region around 10 miles apart - the varroa treatment regime was more or less
identical.
Lies, damn lies and statistics.
