They are 67-72 inches long and weigh between 4.5 and 5 kgs. Their head and back is black while their neck and front is white. They are characterized by a white line that goes from the neck area behind the ear and the eye to the front without being over the peak. It has a black "U" on the chest with white edges. Its beak is flattened vertically with a pink basal area and surrounded by a pink eye. Their legs are a dark gray.
They nest on beaches, dunes or clay hills. Their nests are in terrestrial galleries where it is possible to dig or in bushes. Usually they put 1 to 2 eggs at a time.
They feed on small sardines, anchovies and pejerretes along with crustaceans and cephalopods.
Habitat: Coastal pelagic and rocky islets.