How Big Should the Hive Entrance Be?
P. Michael Henderson
After I replace the woodware in my oldest hive, I had to build two new brood boxes and a new hive bottom.
Brood boxes are a standard size so I didn't have any questions about how to built them. But when I went to build the new hive base, a question occurred to me - "How big should the entrance be?". It seems that many hive bottoms have a 3/4" space across the front as the entrance. But obviously, bees don't need that big of a space to enter and depart the hive. One of my new hives was in a cable TV box and only had a hole about two inchs long and about an inch wide. The bees seemed to deal with that small entrance quite well.
I just can't see why we need such large entrances on our Langstroth hives. A small entrance will allow the bees to defend the hive easier and may require fewer guard bees. On all my hives, I've blocked off half, or more, of the entrance and the bees seem to do quite well.
My question, now, is whether there's an advantage to making the entrance less "tall". That is, whether it would be better to have the entrance slot something like 3/8" (or even smaller) instead of 3/4". We know that the forager bee enters the hive and hands off their nectar, pollen or water to a house bee. Where does that handoff occur? At the entrance or on the comb? If it's on the comb, the forager has to get to the comb, which means the forager has to go to the side of the hive and climb the hive side until she can get access to the comb. Then, she would have to get to the center of the hive where the brood and nurse bees are.
Maybe a narrow hive entrance would allow the forager to access the comb in the middle of the hive without having to climb the side of the hive.
Here's a few pictures of bees in a cable TV box. After I removed the bees that were in this box about a year ago, another swarm moved in and set up housekeeping. A few days ago, I opened the box - just enough to peek in - and they have a fair amount of comb built in the box. Maybe I can do a cutout on them one day - if I can find someone to take the hive.
Here's a view of the cable TV box in it's "natural surroundings". It's on the property line between two houses and the homeowners seem to leave the hive alone.
Here's a closer view of the cable TV box. The opening is approximately at the end of the arrow. It's a hole that the technician would used to remove the top. The shrubbery and vines have grown over the hole, hiding it.
It was hard to get a good picture of the entrance because it was in deep shadow. But I think this picture is good enough that you can see how small the hole is, and yet the bees manage to use it effectively. The bees were pretty mellow while I was taking these pictures. I was there for quite a while, very close to the entrance, taking shot after shot, trying to get one that showed the size well. They'll probably make a good hive.
[Update 2/25/2018] I took some pictures of an identical Cable TV box - that does not contain bees and is not covered with foliage. Here's a view looking down on it.
The hole is keyhole shaped, and is about 1 and 1/8 inch across.
And about 2 inches high.
This seems to provide plenty of entrance for the bees.