What is the name of the salt-excreting gland above a penguin’s eye?

The salt-excreting gland above a penguin’s eye is the supraorbital gland.

Penguins frequently swallow seawater while feeding, so they need a way to remove excess salt. The supraorbital gland filters salt from the bloodstream and releases a concentrated salt solution through ducts near the nostrils.

This adaptation is shared by many marine birds, including albatrosses, petrels, and gulls. It allows them to live and forage at sea without depending entirely on freshwater sources.

The gland is sometimes confused with the uropygial, or preen, gland. The uropygial gland is located near the base of the tail and produces oil used in feather maintenance. It does not perform the main salt-excretion function. Penguins’ specialized salt glands are one reason they can drink seawater safely.