Bees should heal inside beehives overnight

If bees take damage from water, it is unsafe to keep them anywhere near a pool of water, because I've seen them dip down into the water and take damage, just from their own AI. This means that your bees WILL slowly die off if they're within range of water, because they don't heal or avoid water properly.

If they healed at night when they're inside a hive, they wouldn't slowly accumulate damage and die.