Using Mouse Guards on Beehives
As winter approaches, mice may look at a beehive and see the perfect warm home—complete with a food supply. Beekeepers use mouse guards on beehives to keep these furry intruders out while still allowing honey bees to come and go. In this guide, I’ll explain when beehive mouse guards are needed, the different types available, and how to install and use one properly.
As a Master Beekeeper, I speak to other beekeepers in all parts of the world. It is interesting to learn how required beekeeping tools and supplies vary from one region to another. You may not need the same equipment as someone in a very different climate.
Why Your Beehive May Need a Mouse Guard
Not every beekeeper needs to use mouse guards, but they can be very helpful in areas where mice are a common problem.
This is especially true during cold weather when the bee colony is clustered together and less able to defend the hive entrance.
Once inside, mice can build nests, chew comb and damage wooden frames. They may also contaminate the hive with urine and droppings.
A mouse can do a surprising amount of damage before the beekeeper realizes there is a problem. Mouse guards are especially popular with beekeepers in colder regions.
Here in the South, I have not found them necessary for every colony. Your local climate, mouse population and past experience with rodent problems can help you decide whether your hives need this extra protection.
A properly fitted mouse guard creates a barrier across the entrance while still allowing worker bees to come and go.
How a Mouse Guard Works
A mouse guard is a simple barrier placed across the entrance of a beehive. The openings allow honey bees to come and go while preventing mice from entering.
Most guards are made of metal or sturdy plastic and are designed to fit across the lower hive entrance.
They are especially useful during the colder months when bees are less active and may not be able to defend the entrance as well.
These guards come in several styles, and each has advantages and disadvantages. The best choice for your hive depends on your equipment, climate and personal preference.
Types of Mouse Guards for Beehives
Beekeepers have several options for keeping mice out of their hives. Commercial guards are available in different styles, or you can make your own with a few basic materials.
Metal Guards
Metal mouse guards are one of the most common choices. They are durable, reusable and usually attach across the front of the hive entrance.
The openings are sized to allow worker bees to pass through while keeping mice out. Because metal guards hold up well to weather and chewing, they can last for many seasons with proper care.
Plastic Guards
Plastic mouse guards work in much the same way as metal versions. They are lightweight, easy to install and often less expensive.
However, plastic may not be as durable over time. Check the guard periodically for cracks, warping or chewing that could create an opening large enough for a mouse to enter.
Combination Guards
Some entrance reducers include a mouse guard as part of the design. These combination guards can be convenient because they reduce the entrance while also providing protection from rodents.
This can be especially useful during fall and winter when colonies benefit from a smaller entrance.
Homemade Options
You don’t have to buy a commercial guard. You can make your own using hardware cloth secured across the hive entrance.
The important part is choosing an opening size that allows bees to move freely but prevents mice from squeezing through. Make sure the material is firmly attached so a determined mouse can’t push its way underneath.
Choosing the Right Opening Size
The openings in a mouse guard must be large enough for honey bees to pass through but small enough to keep mice out. An opening of about 3/8 inch (9.5 mm) is a good choice for most beehives.
While 1/2-inch hardware cloth is sometimes used for homemade guards, small mice may be able to squeeze through openings this size. For better protection, I prefer a smaller opening when possible.
Whatever style you choose, make sure bees can move freely through the guard and that the openings do not become clogged with dead bees or debris.
When to Put a Mouse Guard on Your Hive
The best time to install a mouse guard is in late summer or early fall, before cold weather arrives and mice begin looking for winter shelter.
Don’t wait until you see signs of a mouse inside the hive—there is no use in fixing the barn door after the cow has escaped.
Before installing the guard, check the hive entrance and bottom board (again) to make sure a mouse has not already moved in. You certainly don’t want to trap one inside with the bees.
Timing varies depending on where you live. Beekeepers in colder regions may need to install guards earlier, while those in warmer climates may not need them at all.
How to Install the Guard
Installing a mouse guard is usually a simple job. Place the guard securely across the hive entrance so there are no gaps along the top, bottom or sides where a mouse could squeeze through.
Depending on the style, the guard may slide into place or need to be attached with screws, nails or staples. It should fit snugly but still allow the bees to move freely through the openings.
After installation, watch the entrance for a few minutes. Bees may need a little time to adjust, but they should be able to enter and leave the hive without difficulty.
Check the guard occasionally throughout the winter. Dead bees and debris can collect behind the openings and restrict traffic, so clean the entrance when needed.
When to Remove it
Mouse guards are generally removed in spring as the weather warms and the colony becomes more active.
With more bees coming and going, the restricted openings can create unnecessary congestion at the hive entrance.
There is no exact date for removal. Watch your bees and local weather conditions. Once the colony is active enough to defend the entrance and the risk of mice moving into the hive has passed, the guard has done its job.
If your area has an early honey flow, be sure the guard is removed before heavy foraging activity begins.
FAQs
Yes. A properly sized mouse guard allows worker bees to pass through the entrance while preventing mice from getting inside. After installation, watch the entrance briefly to make sure bee traffic is moving normally.
For seasonal use, install the mouse guard before cold weather arrives in your area.
Depending on the design, you may not want to leave the guard on the hive all year. Non adjustable models with stationary holes may restrict bee traffic during the honey flow.
Yes, many mouse guards can be flipped over. One side down offers openings for bees to come and go – the other side down allows ventilation but prevents bees from exiting (handy when you need to move a beehive.)
Finally
Here in the South, I don’t need mouse guards on every hive, but your situation may be different. If mice are a problem in your area, a simple guard is an easy way to protect your bees and avoid an unwelcome winter guest.
1/2inch wire mesh mouse guards don’t work! Have them on my swarm traps and mice get in. Ever watch a deer mouse wiggle in? Amazing how big a nest they can build in a swarm trap… and I have never caught a swarm if a mouse was in the trap
Al, perhaps not in every situation but I think 1/2″ would work in many cases. Though I do agree they can get into places you would not think! And, I’m sure a swarm trap would be a cozy mouse abode.