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Archive for February, 2013

Small hive beetle (Aethina tumida)

Small hive beetle (Aethina tumida)

The call it ‘belt and braces’ when you undertake two control measures where one should do; but small hive beetle (Aethina tumida) is a complex ecological problem in the complex dynamics of a beehive and not just a matter of keeping your trousers up. The complexity then couples with desperation, and frankly, an inexperienced mug like me will give anything a go. To extend the belt-and-braces metaphor, I’m in overalls, with an elastic waist band and then the belt and the braces. On top of that, I’m learning to accept that low hanging trousers might be confronting but not obscene, and that mostly what I am after is that they don’t fall down altogether (by which I mean colony collapse).

While the lowlands around Sydney have some of the highest densities of SHB of anywhere in the world (supposedly higher than in its original African homeland), there was some hope that my mountain hive might be spared. Basically, it is in the sort of country that commercial apiarists retreated to when beetle smashed the Sydney Basin industry in the 1980s – higher and dryer than the squelching mid-summer humidity on the coast that beetles thrive in. And mine is about as remote as a hive can be in terms of other managed hives. But I am not spared, and so here, in order of my (as yet only slightly informed) view of effectiveness, are the defences.

Defence #1: The bees themselves

The European honeybee  - Apis mellifera

The European honeybee – Apis mellifera

Clearly beetles can live in my area, but perhaps not ideally. When coupled with the ‘natural beekeeping’ of a Warré hive, this presents Defence #1 –the bees themselves. With husbandry that aims to be more supportive than exploitative, bees could be the best managers of their own colony health. When bees are disturbed they produce stress pheromones. Beetles, the all-too-well adapted buggers that they are, smell it and come to capitalise. Every time you open a hive you stress the bees, so even though you might have their welfare in mind, opening the hive if just to curse the beetles might do more for them than the bees. That said, if you leave the hive uninspected, unattended stores that you are going to take later anyway may be a haven for beetle – while bees cannot kill beetles they do harass them when they can, and can do so more effectively with higher ‘bee to comb ratio’. Comb that the bees don’t patrol is the crazy wild west where lawless beetles have their way. The other thing on my side is some proper freezing winter nights and cold days during which beetle numbers should fall more so than the bee numbers.

A lot of people in Sydney with Warré hives are finding that they can co-exist with beetles, just as long as the numbers can be kept low. Without supers, queen exclusion and other interventions, the bees organise their comb as they see fit, and this seems to provide for them to more diligently harass beetles. If you get rid of them altogether they will only come again from somewhere else, so it is a matter of helping the bees rather than toxically taking over the fight for them. This means traps, most of which rely on the beetles being smaller than bees and having a habit of hiding away in nooks and crannies.

Defence #2: Beetletra

'Beetletra' hive board

‘Beetletra’ hive board

Garden lime, hive junk and dead beetles in the Beetletra trap insert

Garden lime, hive junk and dead beetles in the Beetletra trap insert

Beetletra ‘beetle boards’ was my first order when I discovered that I had SHB. It took some time to get a hold of as they are made specifically for Langstroth hives rather than Warré  and I needed to wait until the only guy who adapts them (Tim Malfroy) had some ready. It went in this Spring and seems to be working. Instead of timber, you have a steel base with laser-cut slits that the beetles take as an ideal cranny to hide from the bees in. Once inside they find that it contains oil, lime or diatomaceous earth, any of which will mess with their breathing gear, suffocating or drowning them. When I had all three traps going at the same time, the Beetletra trap seemed to catch the most.

Defence #4: ‘Die Ya Bastards’

'Die Ya Bastards' small hive beetle trap

‘Die Ya Bastards’ small hive beetle trap

You have to love the name – if you’ve had them mess with your bees and your honey at least. This is an easy to use trap that is simply a plastic envelop with beetle-sized slits and diatomaceous earth inside. You just slip it in the hive entrance so that it sits on the bottom board. Beetles hide, beetles die. It is perhaps redundant if you have the Beetletra board in, but it still caught some when I used them simultaneously.

Defence #4: AJ’s Beetle Trap

'AJ's Beetle Trap' - to be filled with oil or diatomaceous earth

‘AJ’s Beetle Trap’ – to be filled with oil or diatomaceous earth

'AJ's Beetle Trap' inserted between Warre frames

‘AJ’s Beetle Trap’ inserted between Warre frames

When you open a hive with beetles in, you will often see them scurrying away in that first second or so. After that they often do a good job of staying hidden from you and you can easily get the impression that the top of the hive is beetle central, possibly just because that is where you tend to see them.

Maybe these will work for you if you are a very frequent hive-opener, but if not, they have a down side – the bees build comb onto the traps and then every time you take it out you damage some comb. Bees get annoyed, get some extra work to do and presumably get stressed; which is then a slight tip in the balance towards the beetles. If it turns out that the other traps are doing a reasonable enough job of catching beetles, this suggests to me that perhaps the AJ’s Beetle Traps are not ideal.

Defence #5: Everything else but poison

Of course I will kill a small hive beetle on sight for one thing. I have also tried to put my new hive location on a hard substrate so that it inconveniences the beetle larvae who hatch out and bury themselves to pupate (siting a hive in a chicken coop is said to be good because the chooks stand a chance of nabbing them during this process). And I don’t do any composting near the hives because I have heard that beetles will live in compost bins – this may have been people seeing similar beetles in compost, but like I say, I’ll try almost anything. Except chemicals.

And then I will just keep on reading, listening to others and picking up on whatever else I can to give the bees the best chance I can. It is not too much of them to ask of me – I’m going to steal some of their honey after all. Any further advice or comments are more than welcome.

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