Entrance reducers can annoy your honey bees

An entrance reducer is simply a barrier placed at the entrance to a beehive that reducers the size of the opening. They are usually made of wood, but can also be made from metal or plastic.

Many entrance reducers—especially the wooden ones—give you a choice of two entrance sizes. Others have just one size. Some of the metal and plastic ones are continuous.

There are many reasons to use an entrance reducer, although they are almost never used at the height of a honey flow.

  • Entrance reducers may be used to protect a weak hive from invasion by robbing honey bees or yellow jackets. A hive with insufficient numbers of bees may find it difficult to defend a large opening. A smaller opening gives them a fighting chance.
  • Entrance reducers are often used in the winter to reduce drafts through the hive, to keep snow and rain from entering, and to discourage small mammals—such as mice—from entering.
  • Entrance reducers may be used during treatments with essential oils or organic acids. These treatments—which are alternatives to regular pesticides—are used to control mites. To use them, the beekeeper must make the hive into a fumigation chamber which will contain the compounds. Reducing the entrance is one of several steps that allow these alternative treatments to work.

The size of entrance you select will depend on your purpose as well as the strength of the hive. If you use an entrance reducer during the winter months, it is important to place the opening at the top of the reducer rather than at the bottom (see below). This is so that the entrance does not become blocked by the layer of dead bees that frequently accumulates in cold weather.

The photos below also show that painting the reducers is not a good idea. I painted these and used them during the height of yellow jacket season. The bees were not happy. As you can see, they tried to remove them by chewing. They stripped the paint, rounded the corners, and carved long grooves in the wood. It is obvious now that the entrances were too small for the number of bees in those hives.


The entrance at the top of the reducer allows the best bee passage.
An entrance at the bottom of the reducer may become blocked by dead bees.

Over-crowded bees have chewed the paint and rounded the corners.

Bees carved a groove along the length of this reducer.


Cheryl Guye

This told me exactly what I needed to know about positioning the entrance reducer. I had it right, but was not sure.

steve shapson

I just became the owner of two new hives with new bees just in as of April 7th, 2012. I was told to use the reducer with the large opening now, even though it is still chilly. The hive is new. Am I making a mistake or does it make a big difference with a new hive? Will using a reducer (large opening) reduce the activity or productivity of the new bees? Is there a well written protocol of using reducers? I’m in southeast Wisconsin. I’ve read conflicting information on reducers on the web.



You should have no problem using the reducer with the large entrance. With a new hive the bees are not trying to protect their hive from robbers or predators because there is not much there to take. I would go so far as to say you don’t need any reducer at all at this time of year. The reducer is not used primarily to restrict airflow, but to make an entrance hole that is small enough for the bees to defend.

Fall is different. In fall robber bees are a problem and predator wasps are a problem. In the fall you need to watch carefully. A big, boisterous hive will have no problem with a big entrance, but a small hive needs more help.

Since you’re new at this, and you want to feel comfortable, just use the larger entrance for now. When you see your bees start to come and go like crazy, then remove the reducer completely for the summer.

Steve Shapson

Thanks Rusty for the fast reply. I will take your advice. My beekeeping mentor had told me to leave the reducer off for now and put it in when it gets much warmer.



I’ve never heard of adding a reducer in warm weather when you’re trying to build up a hive and store honey and pollen. You want the bees to move in and out easily and quickly with no obstructions. As I said, be concerned with a weak hive in the fall. During spring build -up you want them to go like hell.

Deborah DeLong

I agree! I hardly ever use entrance reducers any more, especially during the honey flow.

richard beaumier

In mid-december I am seeing a 1″ opening reduced to 3/8″ wide, with dead bees aligned, facing out. What are they telling me?? I live in NH and the temperature thusfar has dipped into the high teens. There is more than one hive doing this, and breeds vary in the 20 +/- hives I am observing.



Bees die every day all winter long. When temperatures are warm enough, the undertaker bees fly them away from the hive and drop them. When it is too cold, the bees accumulate on the bottom board awaiting disposal in warmer weather. They may be lined up as you describe because they bees had “plans” to haul them away but left they at the entrance when they realized how cold it was.

Dead bees can get very deep. I like to take a small stick and push it in the opening to keep it clear. Sometimes I take out the entrance reducers and reach it with a long stick, screwdriver, or hive tool to pull some the dead bees out to make room for more and to keep the entrance clear.


I have the narrow part of the hive bottom open…no reducers. There are a lot of bees, or so it seems. The opening is 3/8″. Is that too small for a hive in FL? The package has been in there 48 days and I can hear a hum in the deep and the medium. There was one empty frame in the deep last week…I havn’t checked to see if they are building in the medium yet. I am considering turning the bottom board over and using the wider entrance, possibly with reducers. Am I jumping the gun? Should I wait awhile?


Should you use two brood boxes in the spring and all year long so bees have more honey for winter?



I think at least two deeps (or three mediums) is a good number for most places. Up here in Washington, I use three deeps.


I’m a new beekeeper. I installed my two bee packages one week ago, one deep brood box and a feeder in each.
At what point do I add the next brood box, is it a percentage of the used frames? Thanks a lot!



Wait until the first brood box is 70-80% full.


New BK with new hive. Today I added a slatted rack between bottom board and lower hive body. This evening watching them, they were wrapping up something in white at the entrance. Seemed like it was smaller than the bees themselves. An intruder? They don’t usually wrap their own when cleaning and taking away, do they?



I don’t know what you mean by “wrapping up.” Bees often dispose of defective pupae, which are white, but they just carry them out. I don’t know that honey bees wrap anything.



I know that there are many variables, but on average how long does a new bee package take to fill 70-80% in a deep brood box in northern MI, when shall I take a look see? I don’t want to bother the the little creatures, they are very busy. It’s been 9 days since their introduction to the hive.

P.S. Watching my bees is truly hypnotic. That info I plugged in 36 years ago in 11th grade was right. Beekeeping would be my best career choice…

Thanks to all of you, Scott



My crystal ball doesn’t get the northern Michigan channel. But you are right, there are many variables, not the least being whether you are in a nectar flow or not. In a serious nectar flow it would take only a few days; in normal conditions much longer. I would take a look at the end of two weeks. You don’t need to tear apart the hive, just take off the top and peek in—they will hardly notice the intrusion.

And yes, they are hypnotic. I never get tired of watching them.


I was checking my sugar water feeder yesterday on my newly installed bees and hive of 10 days and discovered a lot of mold on the inner cover above the liquid. This made since to me, as there is no outlet for the evaporation. Obviously this mold needs to be removed but how do I thwart its future advance and is this a common trait of a hive?
P.S. The bees have used very little of the sugar water and I taste it every time and it’s fine. Can I remove this supplement?
Thanks, Scott



Moisture and mold are common problems in bee hives. This site has dozens of articles about hive ventilation, and many include lots of good advice from readers. Just search by using “ventilation,” “moisture,” or “condensation,” in the search box and you’ll find them.

You can wipe the cover with a rag and some bleach to remove the mold. If the bees are not taking the syrup, you should remove it because it just increases the moisture load and may attract other insects.


I have a hive with a bottom board that was not complete, so there is an entrance in the front and the back of the hive. They fly in both sides. So far, a few months, I haven’t had any problems. But do you think I should reduce the entrance on the back or block it altogether?



In the spring and summer, it shouldn’t be a problem. But once autumn arrives, or if you go into a nectar dearth, your bees will have a hard time defending two entrances from robbers and wasps. So, yes, I would block the back entrance.


Hey Rusty….

A newbie here. My new bees went in the hive in late April here in Michigan. I was told to wait until the super was 70% before adding another super. The bees still have not started the 4 outer frames; I see eggs and larvae. I’m beginning to worry about them for winter. How can I help them? I still have entrance reducer at large opening, should I remove it completely?



You can take out the reducer, but I doubt it will make much difference. You can even add another brood box, but that won’t make much difference either, except the bees will probably built up and not out to the sides. They can only go as fast as they are able. Perhaps the colony is small, maybe the nectar flow is past, maybe the queen is not stellar, maybe it has been too cold, too hot, too wet, too dry. It’s hard to say. Short of feeding them and/or re-queening them, there isn’t much you can do.


Hi Folks,

When I take off the inner cover the bees have been building cells on the underside. Should I remove this wax and honey and possibly larva or leave it alone? Is there other areas that should also be kept clean?

Thanks, Scott



You should remove the wax comb from there and anywhere else that makes inspection difficult. If you leave it in place, it just gets harder and harder to manipulate the frames. Pretty soon, you end up damaging more bees than you would by removing it in the first place.


Rusty and the gang,

I’ve got a few questions. I have 2 hives. Before going on my vacation I checked both of my first brood boxes to see if it was time to add the second box to one or both. The south facing box was approximately 90% full so I added the second box; the north facing box was at about 60% so I did not add a second box.

When I returned from my 16-day vacation I checked the north facing hive and it was about 100% full so I added a second box.

Since adding the second box to the north facing hive on July 29th there has been a lot of activity with bees preening one another and many bees dead and dying to the point that there are some cadaver beetles eating the dead!

I know with so many bees there is going to be many dying daily. The south facing hive does not have many dead or dying on the ground which is about two feet below the hives. Could it be the north facing hive doesn’t practice the same dead bee removal?

Lastly, what are those bees doing to the ones that they seem to be preening?

Thanks everyone.

And thanks Rusty for all of your answers to my perplexing questions,



Is there any robbing or fighting going on? Could that account for the dead bees? Sometimes hive inspections break open enough honey cells that robbers bees pick up the scent and come arunning. Just a theory.

Bees preen for a number of reasons, including parasite removal, pollen removal, even water and nectar removal. Some of my bees got in to a wet super last week and got covered in honey. The bees then spent a lot of time licking each other free of the stickies. Again, just a theory.

Does anyone have some insight for Scott and me?


We’ve been getting a lot of rain in northern Michigan this summer. I have my 3 hives tilted so as not to have the bottom board inundated with water, though some bees still get mired in the residual water that puddles near there entrance. Would it be OK to put an “awning” –say a piece of plywood on top of the metal telescoping cover?
Thanks, Scott


Hi Rusty,

We just installed two packages. I have left the entrance reducers on each hive with the thinking that while it is around 10-12c during the day it is getting down to around 2-5c at night.

Am I correct in keeping the reducers on for now while the hives get established and the nights are still quite chilly? (Pacific NW)

Thank you for any input!



I don’t know that the entrance reducers will do much to keep the hive warm. It depends on whether you have screened bottoms and/or ventilated tops, upper entrances, etc. In any case, 2 C is not very cold for honey bees; they can do fine in that.

mary hall

I am a new bk and I didn’t put a entrance reducer on either of my new hives.
I have one strong hive and one weaker hive.

the strong hive seems to have made its own entrance reducer…have you ever seen this?



What did they make it from?


Hi Rusty,

I am a new beekeeper in the PNW and so far, a little over a month in from installing my package, the hive seems to be doing well. I was given advice after installing the bees to put the reducer on the smallest setting and I still have it on this setting. Should I take out the reducer completely now that my hive is growing? If so, when do you suggest putting it back in? Thanks in advance!



When the bees are crowding each other at the entrance, open it up. In the fall, at the first sign of robbers or yellowjackets at the hive, close it back down.


I enjoyed reading all the info you have put out. I myself am a new beekeeper have 4 hives that was started in April. Added the next super a week ago. I need to remove the door reducers but worried about mice. Don’t like the metal doorway protectors any suggestions? Or do I really need to worry at this time of year.



Mice are not a problem at this time of the year. They attempt to move in when the weather gets cold. I remove reducers completely in the spring and summer until robbing becomes a problem in the fall.


Can the use of an small entrance reducer cause the bees to swarm?
I was told to use the small entrance reducer on my new hive this year and leave it that way.
The hive was doing pretty well but has swarmed at least three times in 2 weeks. I caught them each time and put them in their own boxes.
The hive was only about 70% filled.

I have since started using the larger entrance. Could this have been a contributor to the swarms?



I hesitate to say yes or no. I think we put too much emphasis on the physical layout of the hive when we’re talking about swarming. Swarming is colony reproduction and the urge to reproduce is strong in any species. So will increasing or decreasing the size of the entrance change the swarming impulse? I doubt it. It may change the timing a bit, but that’s all. Will keeping a tight reign on teenagers keep them from having sex? I doubt it.

Swarming is something healthy, robust colonies do. So what we as beekeepers try to do is get them to do it on our terms, which means splitting before they swarm, or catching swarms (good job, by the way), or making artificial swarms, or whatever. Most manipulations we make within the colony simply change the timing of the swarm.

That said, if a colony is really overcrowded to the point of dysfunction, it may swarm to gain space. But a hive that’s only 70% full is not there.

As far as entrance reducers, I usually take them off the big colonies in the summer and put them back before the yellowjackets or robbers appear in the fall. An entrance that is too small for the size of the colony slows down nectar collection because they have to wait in line to get in or out.


Thanks for all of the great advice and support.

My hive has been very weak. They tried to supersede the queen but I suspect the new queen never made it back from the mating fights because they remained queenless. Unfortunately there must be a very strong hive in the neighborhood because there are constant attempts at robbing.

Even though it’s almost July and there is a strong honey flow, I’ve put an entrance reducer on the hive while I’m trying to re-queen. If they accept the new queen, my plan will be to take off the reducer because the colony will start to grow again. Does this plan seems somewhat accurate? They are bearding at night but I don’t want to take the reducer off too early and get robbers again (I also have a screened bottom board so ventilation shouldn’t be an issue). After all I would hate for the gals to blame the queen and reject her. Thoughts?



Yes, keep the reducer on, especially with robbing bees in the neighborhood. Your colony will need all the help it can get to build up sufficiently by fall.


We had a hive “wrap up” or propolize an entire dead mouse inside the hive one winter!