It's winter, it's warm, the bees are killing each other, and it's my fault. In the fall I made a critical mistake my bees are paying for now mid-way through winter. Back in October I decided to send some of my hives into winter without supplemental feeding. My theory was that, by not feeding, the colonies would avoid becoming honey bound in the spring, and therefore brood up faster. Well, those hives have become so weak (presumably from starvation) that they're being robbed by stronger colonies whenever we have flying weather. I'm trying to stave off their demise by tightening up entrances as much as possible, but they're not going to survive the winter. The decision not to feed was a failed experiment. It's clear now that ensuring a hive has ample food in January is worth dealing with a honey bound hive in May.