The Alligator is a neutral mob, only attacking you if you enter its territory or attack it or its children. However, they do not deal much damage and only have 10 hearts, so they are quite easy to kill.
They usually spawn in swamp and savanna biomes and are quite abundant. Alligators become hostile in water.
Drops
Breeding
It can be propagated by right-clicking on two of them with raw chicken. The red heart and a baby crocodile will then appear.