My very first Langstroth hive did not make it through the winter. It’s always a gamble going into the New England winter. Especially when you only have one hive…you either end up with 100% success or 100% loss (beekeepers often report their winter success in the percent of hives that made it through).
As soon I arrived at my hive last Wednesday (that gorgeous 70 °F day), I knew to expect dead bees. On a sunny 70 °F day, a healthy hive should be busy. Foragers should be coming and going, looking for food, relieving themselves (they don’t go to the bathroom inside their hive), enjoying the spring-like weather. Instead, standing about ten feet away from my hive, I saw nothing. No flying bees. No activity. I prepared myself for the worst.
When I opened the hive, it actually wasn’t as bad as I had anticipated. Dead bees can get pretty smelly. If the bees have been dead for a long time, wax moths will move in and make a mess of the hive. The smell wasn’t overly pungent, and there was no sign of a wax moth infestation. Good.
There was plenty of honey and pollen in the hive which meant I had fed them enough before/during the winter. It wasn’t starvation (one of the few things us beekeepers can sort of control during the winter) that killed them. Also good.
But, what I also found in the hive was Varroa mite poop (that white stuff in the cells). Not good. Lots of mite poop means that my hive had a big mite problem. Many beekeepers proactively treat for Varroa mites (whether it be with chemicals, essential oils, or even menthol cough drops). My bees however, were from an experimental colony and were not proactively treated. There’s always next year (or at this point, this year)!
Aside from spreading disease, mites weaken bees by sucking their hemolymph (insects don’t have blood, they have hemolymph). Varroa mites (bees can also get tracheal mites) are essentially the bee’s equivalent of a tick. But in relation to the bee, mites are much larger than ticks. A bee with a mite on its back is the equivalent of a human walking around with a dinner plate on his/her back. That is one big hemolymph-sucking pest!
When a young honey bee is in its larval stage, the cell it’s being raised in is kept open, giving the mite a chance to enter (see awesome infographic on Varroa mite life cycle here). At a certain age, the young honey bee is capped over to undergo metamorphosis (just like a young caterpillar spins a cocoon to become an adult butterfly). At this stage, the mite sucks on the pupa’s hemolymph, weakening the pupa and leaving behind waste (the white poop). If the honey bee makes it to adulthood (they don’t always), the adult is likely to be weak at best. At worst, the adult will be infected with one of the various disease that mites carry (such as deformed wing virus).
All hives have mites to some degree so they’re not always a problem. If your comb is full of mite poop the way mine was, they are (or were) a problem. If you see a mite on the back of an adult bee, they are a problem. There are a few mite warning signs that are possible to catch before the mites become too much of a problem—that and more detailed Varroa mite information here!