Every hive needs an entrance. When you first set up your equipment, the standard entrance is a gap the width of the hive body between your bottom board and your first box. You should have an entrance reducer to allow you to manipulate the size of the bottom entrance. Not every beekeeper uses the bottom entrance however. Some prefer top entrances only, some run both, and some have several entrances to each hive. What should you do?
Bottom entrances allow the bees to more efficiently keep the floor of the hive clean. They have a landing area for the bees, and you will often see bees there exchanging nectar, grooming each other, or guarding the entrance. They do have downsides as well. A bottom entrance gives skunks, raccoons, and other critters access to bees coming and going. A single skunk eating bees as they emerge from the hive can take out a hefty number of foragers. Mice looking for a warm place to winter can easily reach the bottom entrance and move in, making mess a smelly, chewed up mess of your hive. If you don’t reduce your entrance the bees have quite a large area to guard against robber bees and other insects. A strong hive should be fine, but a weaker one may succumb to the robbing. In the winter the natural accumulation of dead bees from the cluster may become deep enough to block the entrance, and your live bees will be unable to make cleansing flights on warm days. Snow and ice can also block the lower entrance, trapping the bees inside.
Top entrances are generally smaller and have no landing area. During the winter they provide an escape for excess moisture, and prevent bees from being trapped inside the hive. In summer returning foragers have no problem coming and going through a top entrance, although a few may get confused about which hive is home after you remove honey supers and change the height of the hive. A minor complaint about top entrances is that there are more bees “in your face” during an inspection, as there is more traffic at the top of the hive as compared to a bottom entrance only hive. Rain and snow making its way into a hive and splattering the bees is not a problem. Any precipitation that gets blown into the hive during a storm will hit the outer frames and run down the interior sides of the hive.
How to make a top entrance? If you are using an inner cover, it may come with a notch already made for one. Flip the inner cover so that the notch allows the bees access in and out of the hive, then set the telescoping cover on top, slightly off set to avoid sealing the entrance. Popsicle sticks or shims can be placed under one edge of your lid to make an entrance the entire width of the hive. If you choose this route you can staple some window screen over part of the entrance. That way you retain the ventilation but still give the bees a smaller, more easily guarded entrance. I’ve chosen the quickest and easiest, in my opinion, way to make a top entrance. I simply drilled a 3/4″ hole into my top hive body with a wood bore and an electric drill. If I need to close the hive up for any reason, like a robbing situation or to move the hive, I can pop a wine cork in the hole and it’s sealed up tight.
Here’s how I added my top entrances:
This is the only tool you’ll need for quickly making a top entrance, a battery powered or electric drill with a 3/4″ wood bore. Make sure your battery is charged up before you head to the yard. Choose a spot on the top box of your hive, facing either south or east. Try to stay away from the handles and don’t get too close to the edge. Also don’t drill into a knot in the wood. I use budget grade lumber for my hive boxes so I have quite a few knots. You can make one entrance in the top box only, or make a hole in each box you have. In the summer the bees will use all the entrances and you can close them with a cork in the colder months. I drill the top box only, installed a mouse guard on the bottom entrances, and reduced the bottom to its smallest opening.
Beekeeping tip: Its best if you can drill top entrances into your boxes BEFORE they are on the hive. I scraped up the sides of a couple of frame feeders and put a nice little divot in the edge of one frame by not planning ahead. No serious damage but it would have been better to drill them out in the shop instead of on the hives while I’m standing in ice and snow. On the bright side, every hive buzzed angrily at me so I know they have made it this far into the winter!