We all dread the overwintering months when we can’t check on our bees as often, and worry how they are doing. 

After a terrible cold snap in January (-50 is cold for penguins!), and then a warm up, you have likely checked on your hives and taken a look inside. Some of you may have found your bees buzzing happily along, while others have found their colony has died. This can be both upsetting, frustrating and confusing. 

What Happened? 

Starvation: 
It’s true, during the winter months, our bees can starve if the cluster inside the hive gets too cold to reach honey reserves or they run out. 

Excess Moisture or Condensation: 
The next possibility to consider is if they froze to death. It can happen, especially if there is any condensation inside the hive. Moisture or water inside the hive during the cold winter months is a death sentence for any bee colony. Bees can survive cold temperatures, but they can’t survive freezing conditions in water or moisture.

The silent killer in your hive, winter and summer.

Varroa mites: 
Varroa mites were bad in the fall in the Alberta area, so bad that the Alberta Apiculturist sent out letters recommending treatments for varroa mites. Early detection of varroa mites is key to successfully managing them. If varroa mites are not properly treated throughout the beekeeping season, it can destroy an entire colony. Beekeepers need to regularly monitor by testing for varroa throughout the beekeeping season. Beekeepers especially need to test and treat in late summer and/or early fall because winter bees that are being produced during this time must be healthy as they make up the winter population.

Varroa mites are the most deadly pest affecting western bees and can kill bee colonies in short periods of time. Varroa mites originated in Asia, arrived in Europe in 1970 and in Canada in 1989. The parasitic mite attacks honey bees and brood. Varroa mites latch on to an unsuspecting bee and feed off its blood and belly fat. However, mites mainly affect developing brood as they feed and reproduce on larvae and pupae. Over time this causes malformation and weakening of honey bees as well as transmitting viruses. 

Caption: Varroa are darkish red, oval in shape, approximately 1 x 1.5 mm wide. Varroa have jaws puncture and attach themselves to the body of their host. Varroa mites detect honey bees by smell and movement. For a real close up look click here. Image: February 2020. Dead mites from an overwintered hive.

What should you do if your bees have died? 

First thing you should do is look at your hive and see if you can detect any moisture, disease or anything else that may have caused your colonies demise. Do your best to take any samples you need, photos and get a second opinion from a fellow beekeeper, mentor or us! As soon as it is possible, get in your hive and clean it out.  Once clean, cover any entrances with mesh so air can circulate, and flying bees in the spring can't rob the honey out.

If it’s varroa or starvation, reusing stores and drawn wax is generally okay. Brush off the dead bees, rap the frame flat to dislodge some stuck in the cells. These drawn frames will be ideal for adding Nucs or Pacakge Bees in the spring. The new bees will clean out any left over bees in the spring.

If there is any mold (unless it is black mold), wipe off the frames and any capped honey. Scrub any hard surfaces. Air all items out and then freeze. Save as much comb as possible. The comb, honey and frames may be used in the hive again. Bees can clean some mold, but why not help them out so they can focus on their work! 

Note: If there is any black mold, throw out the foundation (or melt for other uses). Clean frames thoroughly, dry, freeze, and reuse.

Losses can be tough, but spring is around the corner, and an exciting beekeeping season is about to kick off! If you lost a hive, you need to order nucs or package bees to get started again in the spring!