Entrance reducer for new package

I installed my first package into the hive 10 days ago. I have a wooden reducer with the wide opening side allowing the bees to come in and out. On day 7, I noticed some carpenter bees at the entrance. Should I use the smallest reducer size at this point since the hive is so new and small?

The picture shows the current width of the opening and the carpenter bees.


For a full strength colony, you don’t need any more than 15 sq.cm. as an opening. Just calculate how wide it needs to be based on how deep it is. Therefore if the colony is half strength, it would only need to be 7.5 sq.cm.

I think that may have a typing error. Full 15, half 75 ?
Did you mean half 7.5 ?

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Are those carpenter bees? Not like the ones around here. Looks like a honey bee with a black abdomen… do you know if your package supplier has hives with European black bees or something like it?

I’m new at this, so made my best guess based on the picture. I’d be happy to hear these were not robbing bees.

My reducer has 2 sizes…

11cm wide
2cm wide

Since there’s sugar syrup and a pollen patty inside I suppose the smallest size is best for now?

2cm just looks so small

Entrance looks good small!

Were the bees fighting? From your picture it looks like they are fanning, which would suggest that they live there…

Thanks Sam, 7.5 it should be.

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Hi Fred, 2cm might be too small. Even with the pollen patties & sugar syrup inside the hive, the bees still need to be able circulate air in & out of the hive. Work on 7.5 sq.cm. Depending on how deep the entrance is will determine how wide it needs to be. For example: if it is 1cm high, it needs to be 7.5cm wide. As the colony builds to full strength, you can increase the size to around 15 sq.cm. In that case, ideally you’d place one on each side so that the bees can use one side to draw the air in & the other side to expel the air out.

@FredM where in Colorado are you? Still getting much snow or freezing temps?

I’m near Fort Collins. It’s warm during the day but potentially the 30s at night.

If you’re getting highs above the mid-50’s then you could open it up to the larger size if there’s a traffic jam at the entrance. But you will likely never need the entrance fully open, even when the colony is full strength.

You can block the middle, leaving a total of 15cm^2 between the sides with whatever works for you (if you use grass or something similar then the bees can open it up more if they want) once the colony has reached full strength but you will likely need to reduce it again the late summer and fall to minimize robbing and winter to keep out drafts and rodents.

If the bees can come and go without lining up and having to push past each other to get in then your entrance is big enough, a larger opening than “big enough” is detrimental.

If I guess correctly, snow in May isn’t unheard of in Ft. Collins?