The Pandoran Otterfin (Na’vi: Zukzuk), is an amphibious Pandoran mammal that is reminiscent of the Terran sea otter. These playful creatures are highly social, engaging with many other species including the Na’vi. As both predator and prey, the Zukzuk has many adaptations that help it navigate its environment.

Along its dorsal line, the Zukzuk has flexible armor plating flaps, which can be opened and closed deliberately and are used for a variety of social purposes. When closed quickly, they create a clapping sound that can alert other Otterfins of threats or indicate discovered resources. This sound may also indicate trust or affection, which is typically accompanied with the release of bubbles from the flaps.

As an amphibious mammal, the Zukzuk can hold its breath for up to ten minutes at a time. They primarily live in the water, but can often be found eating or resting on rocks and beaches. Its jaws open in four directions and can be used to clamp down on crustacean shells so that it can pry them open with its hand-like forepaws. The coloration of the Zukzuk varies wildly across Pandora depending on the environment.