“Wasps are killing my hive!!!” This is a common panicking complaint that I hear from a lot of beekeepers this time of year. Some beekeepers have even witnessed a sharp colored yellow jacket hauling one of their bees right out of the hive. Wasps are in full force in the pacific northwest in late summer and can really put a damper on any barbeque. You’ve likely noticed these nuisances on the protein items on your picnic plate – burgers, hot dogs, pulled pork, and the list goes on. Wasps love meat, and they also love the protein in a beehive – larvae and other bees.
While these pests can really be irritating, I have to break some honest news. They aren’t likely the main culprit in the death of your beehive. It’s possible, and probable, that your hive was weak from another cause. This weakness disables the hive’s ability to defend itself, leading to a more noticeable presence of wasps that is visible in conjunction with a noticeable decline in a hive’s population and health.
So, what’s the problem then? If wasps are intruding a hive, what could be the main issue causing the hive to be weak? It’s not an easy answer, so I encourage beekeepers to do a thorough inspection looking for areas in the brood that just don’t look right. There’s a chance a hive could be fighting off American Fouldbrood, a nasty bacterial disease that requires immediate action. Was the hive strong throughout the rest of the season, with a large population and strong stores of honey? If not, maybe the hive’s queen has been failing for quite some time, and the yellow jackets are now taking advantage of that weak hive. The most likely situation here, however, is a high varroa mite population in the hive. Varroa mites weaken the hive, introducing other diseases and pathogens leading to their overall demise. No doubt here; varroa mites are easily the leading contributor to poor hive health. So, if you see yellow jackets attacking bees in your hive, do a mite count and treat if needed! Another great tip to help your bees protect themselves against wasps is to place an entrance reducer on the hive (like the pictures below). This is a simple piece of wood that blocks about ⅔ or most of the entrance to reduce the amount of space that the guard bees have to protect.
The phot above is a photo of my hives with entrance reducers in place. You can see that for one of the hives I use a piece of scrap wood that I have laying around. Anything that will block the entrance will work as long as it stays in place.
Wasps might be the last straw to your weak hive, but dive in and make sure there isn’t another problem you can address! Keep your bees buzzin’ y’all!