Its immense size is the reason for its popularity. Wailord watching is a favorite sightseeing activity in various parts of the world. Wailord is the largest of all identified Pokémon up to now. This giant Pokémon swims languorously in the vast open sea, eating massive amounts of food at once with its enormous mouth. The biggest of all Pokémon. It can dive to a depth of almost 10,000 feet on only one breath.
Pokédex entry #321
Wailord in Pokémon GO
It's possible to hatch Wailord from an egg?
No, Wailord can't be hatched.