Complex sentence: Hooded seals live primarily on drifting pack ice and in deep water in the Arctic Ocean and North Atlantic, although some drift away to warmer regions during the year, although their best survival rate is in colder climates.
Split into simpler sentences: Hooded seals live primarily on drifting pack ice and in deep water in the Arctic Ocean and North Atlantic. Although some drift away to warmer regions during the year, their best survival rate is in colder climates.