Related Topic: Honey Bee Parasites, Pests and Predators - New slide set, viewable on Web

Mice are serious pests of stored combs and active honey bee colonies during the fall and winter months. These rodents chew combs and frames to make room for building their nests. Mouse urine on combs and frames makes bees reluctant to clean out these nests in the spring.

Adult mice move into bee colonies in the fall and usually nest in the corners of the lower hive body away from the winter cluster. Colonies located in fields or at the edges of woodlots are especially vulnerable. Mice can successfully build a nest even in a strong colony. They move in and out of the colony while the bees are inactive, and their nests furnish additional protection. Their activity may disturb the bees but the greatest damage is from the nests.

Early in the fall, hive entrances should be reduced with entrance cleats or hardware cloth (three mesh to the inch) to keep out the mice. Chase away any mice found inside a colony, then remove the nest and restrict reentry. If comb chewing is extensive, replace the frames. When bees repair damaged combs, they replace worker-sized cells with drone comb.

Combs in storage should be protected from mice by covering the top and bottom of each pile of supers with a queen excluder, wire screen, or outer telescoping lid.