Gentoo Penguins are one of the two species introduced in version 1.5j.
In the wild, Gentoo Penguins behave like other animals. They only spawn in ice plains or ice mountains. When attacked, all other Gentoo Penguins around will get mad and attack you. Their call lengths vary based on their health.
When right-clicking any Gentoo Penguin with a raw fish, there is a 1/3 chance it will be tamed, even if it is angry. Tamed penguins wear red bow ties. You can shear a tamed Gentoo Penguin by right-clicking it with shears in your hand. There is a 33% chance it will drop black or white Penguin Feathers, but a 60% chance it will become angry and attack; however, other penguins will not attack you in this situation. Note that tame penguins can be bred with wheat.
Gentoo Penguins will drop 0-2 black Penguin Skins on death.