Dragalmise clings to the seafloor where it spits out poison at those who try to eat its algae. It is known to lurk near carcasses of Wailmer and Wailord, feasting on bones and rotting flesh.
The soul of seaweed adrift in the waves became reborn as this Pokémon. Their poison is strong enough to eat through the hull of a tanker, and they spit it indiscriminately at anything that enters their territory.