In the backwaters of beekeeping, a bitter debate is raging between the proponents of the so-called ‘mite-bomb’ theory and its opponents who claim it is stuff and nonsense. It isn’t the friendly sort of discussion beeks may have over tea and cake; discussing if you need matchsticks under the crown board when overwintering bees, goodness no, it is a debate with firmly entrenched opinions which each think the other side is either flat earthers or in the pocket of chemical companies.
In short, critics of those beekeepers who choose not to manage mite populations and allow them to die to say those actions kill other beekeepers’ hives. They claim varroa mites travel from the collapsing hives to nearby apiaries and overwhelm healthy hives leading to their demise as well.
This article in Bee Culture provides a more detailed narrative.
I’m not in the business of telling beekeepers how to manage their bees. So, I don’t intend to provide commentary on differing opinions on bee husbandry.
However, I do find the process of how varroa mites move from one hive to another fascinating and if you do too, read on.
The role of cuticular hydrocarbons in hives
Cuticular what now?
Insects’ cuticles, the outer layer, are coated with a layer of hydrocarbons – hence the name cuticular hydrocarbon. Its primary role is to stop the insect drying out. However, it also plays another important role in insects as a means of communication.
There is extensive research demonstrating that the chemicals signatures of these hydrocarbons play and important role in social insects’ communication mechanisms.
For example, in 2003 a study published in Nature described how researchers observed that ants could identify not only the tasks its nestmate was undertaking but also use that information to decide what task it needed to complete.
The context of honey bees you won’t be surprised to find out that forager bees have a different chemical signature that nurse bees.
How does varroa select the bees they hitch a ride on?
To understand how varroa move from a collapsing colony to a new one is it important to understand if varroa has a way to distinguish between different types of bees.
Work done by Dr Cervo and the team determined that given a choice varroa mites had a preference to attach themselves to nurse bees. From the mite’s perspective, a nurse bee will inevitably lead to new brood cell and a juicy fresh larva to raise more varroa on.
As a colony starts to collapse the population decreases to the point that the bees hydrocarbon signature becomes less distinct; resulting in phoretic varroa choosing both nurse and forager bees.
The other consequence of the declining colony population is an increased insistence of robbing.
Varroa will also readily attach themselves to these robbing bees and therefore make their way into other hives.
There is no question that mites have a mechanism that allows them to move from hive to hive, especially, if they have exploited their hosts to the point of colony collapse.
Intervention free beekeeping?
From my perspective, the real mite-bomb debate isn’t treatment or treatment free beekeeping but rather interventionless or interventionist beekeeping.
Being treatment free doesn’t mean you can’t make interventions in the colony to reduce the impact of varroa on your hives. There are plenty of bio-technical measures that can be deployed to manage mite levels within the colony which do not require chemical treatments that mimic how feral colonies are coping with varroa in the wild.
If you aren’t intervening in your colonies, even just to monitor health, you probably aren’t beekeeping.
I am hopeless at getting equipment cleaned and prepared over winter BUT this year I promised myself it would be different! No more panics or searching for substitutes! Now that the bees are flying more often and bringing in pollen, it’s time to get my act together . . .
Robbing screens are a very good thing to have ready at the end of summer so why not get ahead and make them now? I talked about them in our first podcast. I used them last year when a very aggressive episode of robbing started at my apiary. It was very stressful and alarming, and that was just for the beekeeper, never mind the poor bees! Full supers of honey disappeared, some colonies were badly weakened and members of the public upset. Not an experience I want to repeat.
Robbing screens helped to restore some order in this chaos. There are various designs out there but some of the more sophisticated seem to involve carpentry skills that I unfortunately don’t have. A simple but effective design is an easier and cheaper option for me.
Design for a basic robbing screen
This is the design that I use:
How does it work?
Its very simple: the screen is pinned over the hive entrance, long ways. The bees that live in the colony will enter through the V-shaped gaps at the sides. The robbers, who are chancers that zig-zag in front of the hive entrance, will be confused and won’t work out how to get in.
With the screen in place, you don’t have to reduce the hive entrance which is much better for ventilation and reducing heat in the colony.
You can use gaffer tape to close off one end of the entrance, leaving the bees with one side entrance that is easier for the colony to defend.
Remember though that this is just one tactic in the war against robbing and it won’t work in isolation: you still have to follow the usual rules to ensure that your apiary is a harmonious place! You still need to ensure that you don’t feed during the day, that you feed all colonies at the same time, that you don’t leave syrup or comb lying around and that you don’t open colonies at the end of summer without very good reason . . . ok, lecture over!
How to make a simple robbing screen
I bought the mesh from an independent local hardware store and assume it’s widely available:
It came in one large sheet, approx 70cm x 70 cm. It is important that it is thin enough to cut with scissors and fold into shape by hand. The gauge is small enough to stop bees passing through but large enough for ventilation.
Using kitchen scissors, I cut a piece long enough to cover the hive entrance and wide enough to fold three times. I tend to eyeball measurements but if I had to guess I would say the dimensions are roughly 25 cm x 15 cm (please measure against your own hives first!!).
Make the folds by turning and pressing the mesh under and over until it forms an approximate ‘W’ shape when you open it up:
Because the mesh is sharp, I line the entrance points (the V points at the sides) with some gaffer tape to protect the bees. The pen is pointing to the entrance that the bees use:
Here is another version that you can make which is a bit more fiddly but effective nonetheless. The flat sides are pinned to the hive. The bees enter through the top:
I hope that’s shown you how easy it is to make a robbing screen. And to show you a robbing screen in action, click on the link below to take a look at a video of the robbing frenzy in my apiary last September. The screen immediately stopped the robbers getting in and things settled down despite the severity. This year I’ll be fitting them earlier to prevent robbing in the first place!!
Manuka honey is unique. It is the only honey I’ve seen with a security tag attached. It’s expensive stuff. Last week in my local supermarket there was a jar for £35, I’ve seen it double that in other places. A hefty price tag for honey that doesn’t even taste that nice. Manuka honey is lucrative and devious people have been flooding the market with fake manuka honey;
This week I was listening to the recent episode of the Kiwi Mana Buzz, if you don’t listen to them you really should. Margret & Gary covered a dispute between a manuka trade association in New Zealand and the Cornwall based Tregothnan estate who sell manuka produced by the bees on their estates from manuka trees planted over one hundred years ago.
However; compared to the problems of fake manuka the debate if Tregothnan should label its honey manuka is a minor dispute.
In 2013 Food Standards Agency reported that shops in the UK sold over 1800 tons of manuka honey. Surprising given that only 1700 tons of it was exported from New Zealand and Australia. The FSA estimated over 10,000 tons were sold Worldwide.
Manuka honey, what?
Manuka honey is produced from the the manuka tree, a native of New Zealand and parts of Australia. Before the 1980s it wasn’t as popular as more delicately flavored honeys. In 1982 Dr. Paul Molan identified the antibacterial properties of manuka honey. Science confirmed the long traditional of honey being used to treat wounds and infections was based on fact.
Science behind them, manuka honey producers successfully marketed their product to the health food industry; attracting a high premium. Manuka isn’t unique in having these properties. Honey from Scotland, Wales and other parts of the World all have research replicating the manuka effect. Good honey is simply good for you.
Yes, people even fake honey.
Manuka isn’t the only type of honey to fall victim to honey fraudsters. Honey is one of the World’s most counterfeited food products. In 2011 the Food Safety News published a study showing that three quarters of honey sold in the USA had all it’s pollen filtered out. This is done so the pollen cannot be used to identify where the honey comes from. You could well be eating honey from countries treating their hives with antibiotics or toxic chemicals banned in Europe and the USA. Honey fraudsters also routinely mix honey with corn syrup to increase its volume.
So how do you avoid buying fake honey? Buying from established specialist retailers is a great way reduce the risk. But, I would strongly suggest buying local honey from your local beekeepers. Local honey is surprisingly easy to find. You often find beekeepers selling their honey at food fairs and markets. It is slightly more expensive than the honey you see on supermarket shelves but still a lot cheaper than manuka – why not buy 100% local honey?