Churchill’s Bears and Hudson Bay Winter Obviously, the early freeze-up and the cold temperatures will translate to thicker ice on the bay than in previous years and likely a longer ice season come this spring. That is fairly goods news as our bears do most of their hunting between April and the end of June/early July.The bad news is that actual cub survival often seems to have a negative correlation with good ice years (although cubs that do survive will end up in better shape) (Stirling et al, 1999). From what I can gather, this is usually due to a severe winter (like the one we have) and the lack of insulation in not just the cubs fat layer but, moreso, the mother.