Earlier in the season, I was having a problem with my bees being highly defensive. At the advice of beekeepers on this forum and others, I put robber screens on all of them and it worked like a charm to calm the girls down. But in these past few days I've notice that around 2-4 pm, they are very "antsy," flying all over the place, piling up on the inside and outside of the robber screen, and being very, very loud! They don't seem aggressive, just very active. I'm beginning to think they want to do some cleanout--or maybe they can't evict the drones--with the robber screens on. I wanted to leave them on all winter because I have a serious problem with voles--they did in two of my hives a couple of years ago--but now I'm thinking the girls want something else. Should I take them off for a couple of days to see what happens/let the girls clean out the hives? Should I take them off for the winter? Should I take them off and replace them with mouse guards?