By April, the bees have made it over the hump. The problems they faced in March have not completely disappeared, but a healthy hive needs only a little nurturing now. Brood rearing should really increase through this month. If it does not, your hive has serious problems. As the warmer weather comes, look for many bees returning with pollen loads. The stronger hives will have a significant amount of drone brood in preparation for the mating season.