Credit: David Stephens/Lindblad Expeditions

In a sea of black and white penguins waddling on Antarctica's Aitcho Islands, National Geographic Explorers spotted an extremely rare, nearly all-white Chinstrap penguin this week.

David Stephens, a naturalist on board the Lindblad Expeditions' National Geographic Explorer ship, snapped the photo above of the rare leucistic bird, which he described on their blog as "whitish, but not quite an albino."

Leucistic penguins, sometime referred to as albinistic penguins, have a reduced level of pigmentation and are set apart from albinos due to their pigmented eyes, according to National Geographic. Their "washed-out" coloring clearly distinguishes them from the traditional black and white coat of the Chinstrap penguin.

It's so rare to find nearly all-white penguins, Stephens noted, because the birds' black and white coloring serves as crucial camouflage while diving for fish. Still, the leucistic penguins manage to breed normally, according to Stephens.