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.