crocodile bird, (Pluvianus aegyptius), shorebird belonging to the family Glareolidae (order Charadriiformes). The crocodile bird is a courser that derives its name from its frequent association with the Nile crocodile (Crocodylus niloticus). The Greek historian Herodotus wrote that crocodiles allowed the bird to enter their mouths to remove debris and parasites from their teeth and gums. Although modern naturalists have noted that such a mutualistic association between the two species is possible, and the crocodile bird preys on insects near basking crocodiles, such tooth-picking behaviour has not been observed.