Is it ensure, insure, or assure?
either of the two species of the African genus Buphagus, of the family Sturnidae (order Passeriformes). Both species-the yellow-billed (B. africanus) and the red-billed (B. erythrorhynchus)-are brown birds 20 cm (8 inches) long, with wide bills, stiff tails, and sharp claws. They cling to cattle and big-game animals to remove ticks, flies, and maggots from their hides; when alarmed, the birds hiss, alerting their hosts to possible danger. Though they rid animals of pests, oxpeckers also take blood from the sores, which may be slow to heal