The Great Cormorant is almost 3 feet in length and has a wingspan of 52 inches. Juvenviles have different markings than adults. Juvenviles have a brown breast and white belly speckled with brown, a dark gray head and dark wings. Adults are black birds with a white band across its throat and white patches near the legs. Both adults and juveniles have a yellow throat pouch. They have thick bills and relatively short tails.

These birds nest near the water in trees, cliffs or rocks, making their nests from twigs, debris or seaweed. They offer 1 brood of 2 eggs per year. Baby birds don't leave the nest for 21-28 days and is not completely independent for 63-70 days. Birds will leave the nest, but will return to be fed by both parents.