Heatwave in Adelaide killed 2 hives

I agree Jeff, a solid bottom board would give better insulation than a wire mesh, we need to use all the tricks in the box in this weather to do the best we can for our bees.
I went to my apiary today at 9am, by the time I suited up in my ;Summer, breathable suit my eyes were stinging from the sweat. A very short day on the hives and just had a visual look at the entrances to see plenty of action.
Cheers mate

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Don’t like open mesh floors because the bees work really hard to cool the hive. The cool air is denser and falls out the bottom of the hive, then they just have to repeat the exercise. Extra space above with an insulated roof and baffled ventillation has worked for me so far.

Cheers
Rob.

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@JeffH and @Rmcpb that sounds right- but until it was tested I am not so sure- because the thing about evaporative cooling, which is what bees do- is that it requires drier air to replace the moist air. When I run my evap cooler it really doesn’t work well if you close all the doors and windows. It works best when you leave quite a few open- to allow the moist air inside to be replaced by the drier air. It may be that one entrance is enough for bees- but I wonder if they might get overwhelmed in certain conditions and can’t get the humidity out fast enough? In our dry climate in South Australia- I’d want to test both side by side before i said one was definitely better than the other.

Given that- I think a solid bottom with a ventilated quilt box might be part of the answer. the box provides a barrier between the hive and the roof- whilst allowing excess moisture to be wicked out. I guess if the bees are bringing in a lot of water- and it is evaporating and re-condensing in the wood chips in the quilt box- then as dry air comes in the through the vent holes it would cool the quilt box a little- maybe meaning it works twice to provide cooling before it’s vented from the hive?

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Jack, I like your idea of trying both methods, side by side.

You have to remember that the air coming in through added ventilation, is hot air. The bees are drawing hot air in, then cooling it as they circulate it throughout the hive. Then that cooler air meets the hotter air that’s coming in via ā€œadded ventilationā€. The way I see it, that’s counter productive.

I think the trick would be a well insulated hive coupled with some way of cooling the air via some sort of heat exchanger, before the bees draw it in.

I think that poly hives would be a step in the right direction for a hot climate.

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I hope Poly hives are not the only answer as I am against them in principle. I like the idea of natural timber. The ā€˜Coolgardie fridge on a beehive’ would probably be the ultimate solution- but will require some work and maintenance. Hopefully we won’t have 47C days every year going forward- but that seems to be a slim hope given the way records are routinely being broken and the trend towards a hotter world. I really can’t believe climate change denialists in Australia of all places: cities like Adelaide have a bleak future if we end up with 3 degrees or more or warming.

today I inspected two more hives that had mesh bottoms and they both came through unscathed. They had a bit more shade than the two that died- but were quite exposed at midday. It’s not enough to go on and there are variables to consider- but so far I’ve had no issues ever with screened bottoms- and three hives die with solid bottoms.

EDIT:

ā€œI think the trick would be a well insulated hive coupled with some way of cooling the air via some sort of heat exchanger, before the bees draw it in.ā€

that’s interesting- it suddenly reminded me about a passive cooling/heating system used for houses where you duct cooler air in through the basement or from under the house, then reverse the flow and heat air in passive solar air heaters on the roof in winter. I wonder if you could have a hive with just one entrance- and one addition air inlet- where the inlet runs through a small evaporative cooler? It could be a coiled copper tube wrapped in hessian with wicks into a bucket. The bees could fan hot air out through the entrance and fan the cool air in through the evap vent? I feel a patent coming on :wink:

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So sorry to hear what happened to your hives Jack! It’s heart breaking to clean up the mess. This article by ABK (http://www.theabk.com.au/articles/2016/7/28/a-package-of-minor-changes-to-langstroth-hives-for-major-benefits) recommends a fully base vented and a top insulated (not necessary top vented), similar to the Poly hive design (its a permanent full base vented without a top vent) so a full base vented is the way to go in our hot climate. You will get the 47C days again I guess, probably not every year, perhaps every few years? I used to glue a layer of Broccoli styrofoam board beneath the migratory lid and covered up with a vinyl to stop the bees chewing it while drilling the solid base with a few holes and covered up with a mesh. However I had sold that hive so I can’t tell you the verdict.

My FH 1 and 2 are fully base vented since October, I added an extra quilt box for a top vent (made from the 4 rims of the migratory lid with a mesh), also stuffed my inner lid with the insulation materials used on our house roof, plus a reflective cover to shade them. They only started to beard around 4pm despite getting an afternoon westerly sun from 1pm (the entrance is north facing).

I am currently trying out 2 Poly hives and a Poly nucs with 2 ways entrance, one faces East and other faces West, baking under the westerly afternoon sun … hardly any bearding comparing to the wooden hives. Quite impressed with it so far.

IMG_20190104_145428

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@Semaphore
Jack, apologies if I’ve missed this… Were your brood frames wired foundation, foundationless but wired, or straight foundationless?

Sorry to hear about your loss. I’m now grateful my hive is on the south side of my property.

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Hi Peter, it’s too bad you can’t start any earlier. I was at my bees yesterday before 6, then back home at 8.30 with 7 boxes that I’m going to start extracting this morning before breakfast.

@Semaphore, Jack, I like the way you’re thinking.

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Most of the brood were wired foundation. A few foundationless frames also. Many of them were white wax: new frames- and these slumped the most/worst.

Hey Jack, @Semaphore I found this video to share. It shows the thickness of the timber they use for native bee hives. The reason being that native bees can’t regulate temps like their giant European cousins. I make mine out of 20 mil wood because I have them in full shade. You can see by that video that the wood could be 45 or 50 mil thick, purely for insulation purposes.


Food for thought, cheers
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Hey Jeff, are shb a problem with the native bees?

wow- amazing little hives and cute little supers. Small harvests- but no stings! Does the honey really have a very different flavor Jeff?

back to topic: I inspected all my hills hives today and they came through the heat wave OK. Though very little in the way of honey- not one harvest from any of them yet this year. Lean times.

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Wow…there’s enough aspects of beekeeping to keep it challenging without what you’ve been experiencing with those high temperatures. Sure hope a cooldown with some rain is in the forecast…how much of your season is left to bring in a crop?

BTW…do you have a weather link that you prefer for your part of Australia? Sure would like to see how your weather changes in the near future…

Yes SHB are a problem, or can be a problem with the initial setup of a new hive. I think it’s important not to allow any honey or pollen to fall onto the floor for bees to drown in, that will attract beetles to lay eggs in. That happened to me once.

The first thing the bees do is build a tunnel inside the entrance which makes it harder for predators to enter the hive. Then the little bees are courageous defenders. If a beetle for example enters a hive, they place a sticky resin on it to immobilize it, then completely cover it.
These two videos we took show what great defenders they are:



@Semaphore, the honey is more runny & has a distinctive citrussy flavour & very sweet. It doesn’t keep well, so I found, even in the fridge. I store it in the freezer.

PS Jack @Semaphore, I not long returned home from returning stickies. I did some serious thinking about what you said about the hives surviving the heat that were low on honey.

I think that might be a key to a colony surviving high temps: a lack of honey. A lack of honey means the colony only has to keep the brood at a constant temp. I was thinking how every brood frame should be full of worker brood so that the colony has a good worker force in order to have more workers fanning.

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yep- the 47c day was the almost the final straw this season: here in South Australia commercial beekeepers are saying it’s been the worst year in living memory. the winter was very dry. I have 13 hives left and so far I’ve hardy harvested any honey at all. We still have maybe 4 months of potential season left- so there is still a chance for some autumn honey. We are blessed with a long honey season at least 9 or more months- and the bees are active right though winter too. But I’m not counting any chickens this year.

I guess the official Bureau of Meteorology would be a good start:

http://www.bom.gov.au/sa/

This entire heat thing has me wondering if your type of indoor bee houses wouldn’t be a brilliant idea here too. I assume you do it mostly for the cold- here it’s the heat that bees have to work against.

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@Doug1 @semaphore

They’ve got more hot weather coming. Over here in the West we normally get the weather a couple of days before they do. We just had a couple of 40-43 degC days so they’ll be in Adelaide soon enough…if not identical then not far off. Our saving grace here is usually the Fremantle Doctor…which takes the edge off a hot day fairly reliably (but not always) in the afternoon.

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Jeff- I think another aspect to the honey side of things is the presence of fresh nectar and fresh white comb: in the hives that died it was clear that the very newest white honey comb collapsed the most- setting off a chain reaction. Maybe when there is lots of nectar there is also more humidity than the bees can handle making it harder for evaprorative cooling to work? The one other time I killed a hive when I was moving it it had loads of honey and fresh nectar. But in all three cases there was the same situation; a single brood with a large population. I feel fairly sure if they had had supers on them they would have made it. If we get temps over 42C going forward i will be sure to put supers onto single brood hives just until the heat passes even if they are not ready for their super. I will also make quilt boxes- and shade covers. I will also think twice about situating hives in full sun.

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Well done Jack, it’s a steep learning curve. Quilt boxes, shade covers & out of full sun can only be good things in extreme heat.

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Most of my hives are in full sun. I have put 20mm aluminium sandwich foam insulation in the lids which covers half the vent holes in the migratory lid. Wax barely sticks to it either :wink:. I have painted the lids white and then have a piece of the foam overhanging the hive footprint on top with wooden spacers between to create an air gap with a brick to secure. This works a treat and compared to previous years bearding there is a significant difference. Although we hadn’t had those kinds of temperatures yet we have had +40°C temps. The larger colonys have no entrance reducers either. Pre foam I had bees bearding half way to the ground now nothing on most.
Two hives have supers and two don’t. The foam has a black side and a silver side and when the weather cools I flip the sheet black side up and have it sitting directly on the lid.
(I have plenty insulation spare if anyone around my way would like some.)
My colonys in the shade don’t do well and plan to move them sometime.
But at 47°C, in the shade, yuk. I’m glad that we aren’t copping the highs like we used to and the rest of the country is experiencing what we normally do. :sunglasses:
Gee I hope they aren’t some famous last words…

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Here’s what goes on during the summer inside the insulated beehouse…all hives are working to ventilate a shared space…there’s no reason why you couldn’t help them out with a tray of water on the floor for evaporative cooling. Although the photo shows a lite up area, the door is closed and it’s totally dark inside. If I track in mud, leaves, or grass, they don’t need to be asked to remove it. I’ve noticed dead varroa mites sealed with propolis on the floor. Sure would be interesting if someone tried this method in an extreme hot location.