Last week we had a few chilly days with rain and our bees, being fair-weathered flyers, stayed home. The hive was quiet and there was none of the usual bustling activity in front of the entrance. Since we’ve had nice weather from the day we set up the hive, we hadn’t seen this behaviour yet and even though we were grateful for the rain for the garden, we were hoping for some warmth during the day to allow the bees to get outside.
An interesting thing about bees is that they will not go to the bathroom inside the hive. They keep the inside of the hive very clean and constantly move any dirt or debris (including fallen comrades) out the front entrance. During bad weather, when the bees stay home, they will hold any of their wastes until they get a chance to get outside and relieve themselves. This can be extreme to the point that, when the bees are overwintered in the hive, they will wait almost all winter until the spring warms up just enough to allow them to quickly dash outside.
Even with our three days of cool weather, we saw quite the sight once it did finally warm up. All around the landing board and our patio were little spots of bee poo! While we had read about the bathroom habits of bees during our preparations for hosting the bees, we weren’t quite prepared for the… for lack of better descriptors, size or frequency around the hive!
Like new parents, we immediately feared the worst and that our poor bees were afflicted with a serious bee illness called Nosema.
Nosema “is caused by Nosema apis and Nosema ceranae. It is a microsporidian fungal disease that infects the intestinal tract of adult bees. Nosema can cause detrimental effects on honey bees, colony development, queen performance and honey production” (Nasr, Medhat. Alberta Apiculture: Recommendations for Management of Honey Pests and Diseases in Alberta 2012).
It wreaks havoc on the intestinal tracts of the bees and causes them to have diarrhea. Because the bees try not to go in the hive, you can usually spot Nosema outbreaks by the pattern of excrement that will be all over the front of the hive. To formally diagnose Nosema, you would have to take a sample of dead bees, dissect their abdomens and count the spores under a microscope.
Nosema can eventually kill the entire hive if the bees aren’t able to overcome the fungus. Commercial operations will treat the hives with Fumagillin-B, an antifungal agent, either in a syrup solution or in a hive spray. Equipment from dead hives will have to be irradiated or treated with acids to disinfect it.
After spending some time searching around various beekeeping blogs about what constitutes normal bee feces and what to look for when it is truly Nosema wreaking havoc with bee intestines, we concluded that this occurrence was just a symptom of the cold weather and not the fungus.
We cleaned off the landing board and the rest of the hive just as a precaution in keeping anything nefarious from spreading. Thankfully, with a few days of nicer weather, the bees were back to their bustling activity and taking advantage of using their world as a bathroom (within their 3 km exploring radius) rather than just their front stoop.