The losses are most significant in the winter because bees must survive three to four months without foraging; if disease or pesticides cut their lives short by, say, 10%, that could be the difference preventing a colony from surviving to spring, vanEngelsdorp said. During the rest of the year, honeybees each only live about 35 days, making it easier for beekeepers to manage losses by splitting up the hives that are thriving and starting new ones.