My queenless, cutout bees working brood comb and hopefully making queen cells are now 4 days in a 36" Top Bar hive box. They have a 1 3/8" round entrance on the lower part of the end of one side. Screen bottom. Being concerned about robbing, I'm thinking of reducing the entrance hole size. How small do you recommend?
Thx!
I like my entrance to be full of bees. If there's a real traffic jam I open it up a little but I don't want any open space for robbers to walk in.
A weak colony can defend itself if it only has to fight one or two bees at a time.
A colony has to get fairly strong before they need a hole bigger than one inch.
I agree with Wolfer.
When I've got robbing going on and I've got a small colony, I don't hesitate to reduce the entrance down to 1 bee width. A nuc may only have a bee trying to get in, or out, every 30 to 60 seconds. You just don't need a hole any bigger than a single bee width in that situation because even a single lane isn't being used most of the time!
Once you've got bees coming and going at a descent rate, increase the entrance size in accordance.