Here's a breakdown:
* Harbor seals: Often live in smaller groups of a few individuals, but can form larger groups during breeding season.
* Grey seals: Form larger colonies, especially during breeding season, with hundreds or even thousands of individuals.
* Elephant seals: Live in harems, where one dominant male mates with several females.
* Monk seals: Can be solitary, but sometimes form small groups.
While seals are social, they may also show some solitary behaviors, especially when resting or giving birth.