There is a good write-up in the October 2025 BBKA¹ News, by Clare McGettigan, giving some headlines from their survey, which was carried out in partnership with COLOSS². I understand that a much more in-depth analysis, incorporating results from other countries too, will become available in due course. For now, I will be passing on my views on what it shows, as not everybody reads BBKA News, and I might be able to provide additional references and reading. Come to think of it though, a lot more people read BBKA News than my blog! Oh well.
Vertigo – yuck
Firstly, a quick digression. I recently suffered from an attack of benign paroxysmal positional vertigo (BPPV)³, which is quite horrible. It turns out that plenty of others have suffered with it too, so there appears to be a bit of a design flaw in the human ear (or maybe it’s just another downside to aging). To all fellow sufferers: I sympathise, and hope your otolith crystals remain where they are supposed to, for ever more. Back to bees.
Survey Winter 24/25
Every spring, the BBKA reports back on how UK colonies fared over winter. The latest survey (covering 2024/25) shows average losses down slightly from the previous year – good news on the face of it. But when you dig into the charts and wording, a few points need teasing out. Average overwinter losses were approximately 22% vs 25% last year (self-reported, colony-weighted). Regional variation is wide; some areas fared much better, others worse. This matches the typical pattern in the COLOSS global monitoring project – losses swing year to year and by location. The pattern of winter losses is similar to the husbandry survey by the National Bee Unit (NBU), although the NBU reported⁴ 17% winter losses last year, which is much lower than the BBKA survey (25%).
Solid Conclusions
- Treated colonies generally did much better. Losses were 21% for “treated” vs 34% for “not treated.” Across multi-country COLOSS analyses, varroa treatment emerges as a statistically significant predictor of lower colony loss risk (e.g. Van der Zee et al. 2014)⁵. Treatment-free advocates acknowledge that moving from traditional methods to non-treatment usually results in high losses initially, until resistance is established.
- Fondant makes sense in Winter. Survey responses suggest colonies given fondant in winter fared better than those topped up with syrup. That’s logical: fondant avoids chilling and damp. Just remember, the sample sizes for some feed types were very small.
- Weather narrative is plausible. Mild winters with fewer prolonged snow periods can ease survival. Met Office data confirm that winter 2024/25 was a touch warmer and slightly drier than average in many regions (Met Office⁶). But losses aren’t simply about weather – nutrition, queen age, mite levels, and wasp pressure all matter.
Pedant Corner
- Colony collapse. The BBKA article describes dead-outs with “few dead bees” as “CCD-like.” In reality, this is just a COLOSS coding category. True Colony Collapse Disorder (CCD) is a historical syndrome that’s no longer widely used. I’ve always thought that these types of dead-out are varroa/virus related, but there can be other causes, such as a late season queen problem followed by dwindling and/or robbing.
- Product comparisons. The chart ranking losses by treatment (flumethrin lowest, amitraz mid, OA mixes higher) should carry a big health warning. It does have a warning, but I know what my mind wants to do when I see charts like that, and I’m probably not alone. Hopefully, people won’t all rush out and buy flumethrin treatments.
• Subgroup numbers are small.
• Resistance matters: UK varroa have documented pyrethroid resistance.
• Without proper trials, you can’t treat these as efficacy tables.
Acceptable Losses
I was pleased to see the highlighted conclusion to this BBKA News article:
“Nearly half of respondents believe colony losses of >16% are acceptable, and worryingly, 7.7% felt losses of >41% were acceptable. We should not expect to lose at least one in four colonies every year!”
By now, readers of this blog will know my views on treating bees for parasitisation by varroa mites. I believe that it is part of good husbandry, and it’s especially important for beginner beekeepers to learn this. Perhaps, when they become good beekeepers one day, they can experiment with alternative methods. But many will disagree with me, as is their right.
Willie Robson
It was sad to see an article by Willie Robson in BeeCraft⁷ magazine called “Difficult Times,” in which he reports that his losses were “unacceptably high”. He has been running down treatments in an attempt to get varroa-resistant bees, and seemed to be doing okay for a while, but not so much now. There are multiple stressors which all add up to losses, but varroa and associated viruses are the big one. Willie will be making up nucleus colonies in Spring to maintain colony numbers, rather than reverting to chemical treatments. A brave decision for somebody who earns his living from bees, but I wish him well.
Podcast
Episode 19 of my Podcast goes into more detail about my position on treatment-free beekeeping. For some, it will simply confirm what you know. For others, it will wind you up and make you say rude words. Until next time…
References
- https://www.bbka.org.uk/
- https://coloss.org/
- https://www.menieres.org.uk/information-and-support/symptoms-and-conditions/bppv
- https://www.nationalbeeunit.com/bee-health-improvement/nbu-surveys#
- https://doi.org/10.1371/journal.pone.0131611
- https://www.metoffice.gov.uk/research/climate/maps-and-data
- https://www.bee-craft.com/product/back-issue-october-2025/
