Hi All,
I’m in Sydney Australia and we are in the 2nd month of autumn, the next few nights it’s getting colder than usual and the temps will be dropping to 8-9c. is it time to use entrance reduce to keep some of the warm and protect them from the cold of night ?
Any advice ?
Cheers,
Ed
I would reduce the entrance to at least half. 
Hi Ed, I was doing that myself this morning. Mainly with the nuc size colonies in 10 frame boxes. However it wouldn’t hurt to reduce the entrance by half as @Dawn_SD suggested. Also, if it’s possible, face the entrance away from the cold wind. If you have a sbb, make sure the core flute is in the top slot.
Do you reduce your hive entrances in winter @JeffH?
Do commercial guys use reducers in cooler areas?
I’m in Melbourne and already down to half. Should I make it even smaller? And what to do with the round hole in the super cover? Should it be covered for winter?
I cover the hole in the inner cover completely, year round. My entrance is also half sized all year, but if the colony is not very strong, I would probably go to quarter (or even about 5cm) over winter.
Thanks Dawn. It’s about time I checked on them. I’ll do it soon 
Hi @skeggley, I don’t reduce my entrances as a rule, however I think it’s a good idea to do it. I have mainly reduced the entrances of nuc hives. For example: some nuc hives only have 4 or 5 frames of beesin 10 frame boxes, so I reduced those entrances considerably. We are having an unseasonal cold snap at the moment, I’m even wearing a cardigan under my bee suit:), in the mornings.
I have no idea what the commercial blokes do.
If you have a standard flow entrance, I can see no reason why you couldn’t reduce it down to one third, especially after some of the tiny entrances I’ve seen on this forum.
Out of interest, what would people consider too small an entrance? I’ve reduced mine straight up to a 2-3 bee width this year. Last year I reduced it by about 3/4 the original width, so a larger opening than last year.
@Anon, @Dawn_SD, @skeggley, @JeffH, @Dee, @Michael_Bush, @Gerald_Nickel… Opinions?
Thanks!
Too small is hard to do. However, if your bees are all crowded outside and the box is empty of needed workers, it is too small - I have never seen that, I think the bees would abscond first. The smallest I use for winter is about 3 square centimeters for weak hives. It doesn’t mean that smaller is bad, that is just my experience.
Too be honest I hadn’t really thought about it much until a week or so ago. I didn’t think it was necesary in our climate. I’ve only used sections of wood that block one side of the entrance in my brief career, and every time I’ve removed it I’ve found wax grubs hiding in the corners with silk and debris. Wild colonys don’t close up their entrance and they do fine. My strong Pot colony didn’t have a reducer and it was fine but I guess the question is would it have done better? I do like the idea of keeping it simple but once again it it benefits and advantages them I suppose it could be worth the effort…
I am curious as to what the commercials do, colony and site specifics would also be relevant of course.
I guess I’ll just have another beer and ponder it some more.
Hi Alan, I agree with @Dawn_SD, I believe that the bees need a wide enough entrance so that when they are circulating air throughout their hive, the air coming in doesn’t clash with the air going out, as in the video “City of Bees”.
I think that in a harsh winter environment, it’s more important to prevent cold wind blowing into the entrance than to actually reduce the size of the entrance. Reduce it by all means, however also focus on preventing cold wind from blowing in.
My reducers are 7mm x 80mm and stay in all year
The bait hives have 25mm diameter entrances and seem to attract bees quite happily
Some floors have underfloor entrances so are 7mm x 400mm
Thanks for the comments. It is interesting to see the different approaches. I’m currently going to stay with my original aim and check the hive in a week or two and decide whether or not to increase the opening or leave it significantly reduced.
Based on my last inspection I’m actually anticipating another harvest from my full-flow super while still leaving a full hybrid super for winter. The weather here is still warm-ish during the day (http://www.bom.gov.au/wa/forecasts/perth.shtml) and expected to remain like this for a while, even though it is reasonably cool of a night (it’s all relative I guess…). As commented by others in the forum thread for Perth we are experiencing a second round of flowering for many of the eucalypts 
Mine are all now 2" to 2 1/2" wide and 1/4" to 3/8" tall. All the time.
Hi all,
Just to follow up because I said I would.
The nights have been getting pretty cold for Melbourne. About 7C. I’ve taken off the Super and today I reduced the opening to about 5 cm. I closed the hole on top with a piece of plywood and laid a piece of insulating foam over the top. The hive faces away from the wind and they are still really active and happy looking.
I’m relieved that they seem healthy. Thanks for the advice!
Thank you for the follow up @Nezza! It is always nice to hear what happened. 
Thanks all - was looking for collected thoughts on entrances for my plan to inspect later today. We’re firmly in springtime here and one of my hives looks like it needs a slightly larger entrance about now. Going to try to post with pics & more details later…
When I had 50+ hives in below zero temps at night my hives were down to 2 full depth 8 frame for the brood and the entrances were not reduced figuring the hive numbers was still big enough to make their own heat for warmth. I didn’t loose any hives from cold. Hope that answers your question.
Regards