Although there are many ways to add ventilation to a hive—and there is much room for beekeeper creativity—several issues should be kept in mind. These include predators, robbing, rain, and cross drafts.
Predators include other species that feed on honey bees, bee larvae, or honey stores. For example, in many areas yellow jackets will take any opportunity to invade a hive and eat both bees and honey. Any opening that is not screened—even the main entrance—is an invitation for these aggressive insects. For this reason, a shim placed under one end of the telescoping cover or between honey supers is usually not a good idea because it is almost impossible for the honey bees to defend so large an area.
Robbing bees present a similar problem. In the late summer when nectar flows are in short supply, robbing bees will invade poorly protected hives and take every last molecule of honey. Both robbing bees and yellow jackets can be so persistent that even the main entrance has to be made small enough to be easily defended. This makes ventilation all the more important. In many areas—such as here in the Puget Sound area—robbing, yellow jackets, hot weather, and nectar dearths happen all at the same time.
Ventilation openings also have to be protected from rain. Especially in the winter, a poorly designed ventilation port can cause water to enter the hive and increase—rather than decrease—the amount of moisture that has to be removed.
Another winter consideration is cross drafts. For example, a draft that goes from the center of the lower front to the center of the upper back will flow right across the winter cluster. Many beekeepers recommend that the air flow be directed along the sides of the hive instead of through the middle.
All of these potential problems can be handled with a well-reasoned ventilation system. In future posts I will present some of the solutions used by other beekeepers.
Rusty
I think ventilation is something quite overlooked. Here in North West Thailand the temperature in the shade (in the hot dry season) can reach say 44C (111F) and that is really not fun. The temperature inside a hive has to be hotter. Touch the wax on a frame and you destroy the structure.
The effect from my experience is that if the sun falls on a hive during the hot season (since the sun is in a different position in the sky) then the bees vacate the hive. The frames are all cleared, absolutely nothing is left.
I have also seen that in the hot temperatures the bees stop laying and find it hard to defend the colony – I lost two colonies to ants this year. I have never seen so many ants in one place. But this only happened when it was really hot. Ants are around during the rest of the year but they are not able to overrun a colony at that time. The ants in this case are not the larger red and black ants but the 2-3 mm red ants which really know how to bite.
Whilst shade is the bee keepers friend, I cannot help but wonder if better quality air flow would also be useful.
Peter,
Thank you for writing. It never occurred to me that the bees might have more trouble defending their hive in hot weather, but the yellow jacket attacks I had last year occurred during a very warm (for here) spell of 90-degree weather. At that time many of the bees were bearded on the outside of the hive, allowing the yellow jackets to invade at will.
Another interesting comment you make is, “shade is the beekeepers friend.” I agree with that completely, but that’s not commonly accepted here. Many people here think bees should be kept in full sun. Again, I look at bees in nature and see they like the edge of the forest where there is plenty of shade. Consequently, I always keep my bees in the shade.
You gave me a lot to think about. Thank you so much for sharing your experiences. I will be using your insight in a future post!
Rusty
Thank you for these comments. I live in Florida…hot and humid. My bees have done well in about 10 hrs of sun for 2 years…but am I stressing them out? I do not know how to ventilate the hive. Could someone be more specific? Most of the books I have offer many suggestions for keeping the hive healthy in cold weather but do not go into any suggestions for long HOT summers. Thank you. Franny
Franny,
This is a good question and I have answered it in a post so everyone can read it. You can find the answer here: https://www.honeybeesuite.com/?p=2435. I hope this helps.
The ventilation discussion has been very helpful. A follow up question regarding leaving the screened bottom boards in place over the winter:
Do you remove the “debris board” that is part of some screened bottom board designs. My screened bottom board comes with a slot for a debris board about 1/2″ below the screen. In my bottom board (which was a purchased item not my design) both front or back of the bottom board are open, so even with the debris board left in place air still flows between screen and debris board. Is that sufficient airflow? Or do you recommend removing the debris board all together for the winter?
Bill
Bill,
I do not use the debris board (aka varroa tray) during the winter. However, remember that every area is different. Mine happens to be very wet but not too cold, so I’m not worried about temperature or wind. You have to consider your own climate when making these decisions.