Monday, February 28, 2011

Prenolepis imparis on a Bee Hive

I noticed some winter ants, Prenolepis imparis, scurrying about one of our beehives today and decided to film a brief inspection. Beekeepers I talk to always seem annoyed with ant entering the hive. To be honest I'd say almost all of the ant species in the US don't do any harm. Most of them just enjoy the environment in the hive attic and use it to incubate their brood. A few of the wood nesting species though can do some damage to the hive but it's nothing compared to normal ware and tear of the wood from prying it open constantly. There are a few tropical species of ants that will kill a beehive but nothing for the local beekeeper to be concerned with. 

In this case the P. imparis workers were merely interested in nibbling at the propolis and bits of wax along the side. Ants use tree sap (propolis) as an antibacterial agent. They also have a fondness for the smell of honey I'm sure. I have never found P. imparis colonies to be more than a slight nuisance to my bee hives.  

Below the entrance to another hive the ants were inspecting dead bees the hive was tossing out. A lot of worker bees die over the year and it's natural to remove them from the hive where they're cleaned up by an assortment of ants each spring.

I'm happy to say both my hives are alive and collecting pollen, probably from the maple trees that have just started blooming.


  1. Wow, huge kudos for not automatically going to "Kill, kill, kill!" mode and actually studying the situation. I'd think having ant remove dead bodies would be good for the health of the hive. Interesting post. =)

  2. I think the fear is more that the ants are stealing the honey or attacking the brood in the hive. I've been to a lot of beekeeper's meetings where we open like 20 hives all in a row and people are always alarmed when we find that 1 or 2 hives that have ants in the upper attic part. Usually it's more than just foraging as in my video, often the ants will have moved their eggs up there there and are just living in the space. You can't really do anything about it besides dump the ants out, as any use of pesticide will likely get back into the hive somehow.

    I'd say almost all species of ant in a temperate environment don't pose any threat to a bee hive besides nicking at the wood here and there. As we get more tropical though ants can become more of a problem. Fire ants, Solenopsis invicta, and Argentine Ants, Linepithema humile, pose more of a threat to bee hives. A fire ant sting can kill a honey bee, and the Argentine ants will outnumber the bees and drive them out. I'm not sure how beekeepers deal with that down south. The best solution is probably to just move the hive but that's not always an option. As we get into South America some species of army ant can easily kill a beehive, but thankfully they're not the main menu item for most army ants.