March 26, 2018

Question

I carried out a quick inspection of my colony yesterday when it was warm and noted a number of bees with deformed wing virus (though I treated with api-guard x 2 in autumn and oxalic acid in January). There were also some dead bees part-emerged from cells, which I think could also be an indicator of viruses related to varroa? There is quite a bit of crystallised honey in the brood frames. I saw the queen and a few larvae so she seems to have started laying again, and otherwise there was quite a bit of activity going on/pollen collecting etc.

I was wondering if I should change the brood frames to help with disease control and get rid of the crystallised honey? Possibly as a shook swarm around mid/end of April? Does that sound vaguely sensible? And/or should I be undertaking any more varroa treatment at this stage? I’m currently feeding with fondant.

Answer 1:

Viruses can’t replicate outside their host and don’t even survive for long so comb replacement is of limited value for DWV (but still good to do to counter fungal & bacterial diseases). You don’t mention the size of your colony. Something like a shook swarm is quite a stressful experience for a colony and I wouldn’t consider it for a small ailing one. They also need good weather so I wouldn’t consider a shook swarm until mid-end-April (perhaps even May considering our weather prospects this year!)

Deformed wing and dead emerging bees with their tongues hanging out are signs of parasitic mite syndrome – essentially virus overload. Varroa treatment for PMS is a bit like shutting the barn door after the horse has bolted. The damage has been done and the bees are suffering from viruses. Nevertheless if the Q is laying then there is a possibility that the new bees might develop free of viruses so it is sensible to carry out a varroa count and treat again if necessary. A new product on the UK market claims to be 95-99% effective and can be used in early Spring/late summer – the chemical is Amitraz and proprietary products are Apitraz and Apivar.

Keep feeding if they’re eating the fondant – I’ve found with some of the SBKA bees at WS that they prefer to go up to fresh fondant rather than sideways to granulated honey. There’s very little else to do at this time of year.

Answer 2:

I’d feed pollen supplement/substitute swell as/instead of fondant – depending on how much fondant mixed with pollen. Although the bees are bringing in pollen they are not getting out much at the moment and pollen needs are high.( to produce plenty of healthy young bees.) Also if you want to do a shook swarm in April building up the number of bees now will get hive ready for that. Shook swarm will not clear viruses – but will get rid of the 85% of the Varroa that are in the brood. Amtraz is quoted as being 95-99% effective – but the small print afterwards says – ‘when the brood quantity is low’ – not the case in April!! I also read recently that following a shook swarm if you sacrifice two brood frames after the Q has started to lay in the new chamber you can also dispose of most of the other 15% Varroa that were in the phoretic stage – i.e. on the adult bees when shook swarm done. That leaves a hive with really low Varroa count.