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