secretary bird, common name for a long-legged African bird, Sagittarius serpentarius, related to the hawk and about 4 ft (122 cm) tall. Its crest of black feathers suggested the quill pens behind the ear of a 19th-century male secretary. The bird hunts on foot, zigzagging toward its prey and flapping its wings, and is valued as a destroyer of snakes and other reptiles. Secretary birds are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Falconiformes, family Sagittariidae.

African raptor (Sagittarius serpentarius, family Sagittaridae), the only living bird of prey that hunts on foot. It has long scaly legs, a light-gray body that is 4 ft (1.2 m) long, and a 7-ft (2.1-m) wingspread. It weighs about 8 lbs (3.5 kg). Twenty black crest feathers make it appear to be carrying quill pens behind its ears. Secretary birds kill snakes (their main prey) by stamping on them, flailing them against the ground, or dropping them from aloft. They make their large stick-built nests in thorn trees. Both parents feed the offspring by regurgitation. Secretary birds are protected in most African nations.

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