Crocodile
In historic times the Nile crocodile was found from the mouth to the source of the Nile, but powered river craft and then rifles quickly reduced its numbers and range. By a cent. ago it had almost gone from Egypt. Its former status N of Egypt is hard to determine, but Pleistocene remains have been found in the Mt. Carmel caves and some lived in the Zerka river, still known as Crocodile River, near Caesarea, until the first decade of the twentieth cent. and perhaps rather later. Thus the crocodile would be well-known to the Israelites before the Exodus and familiar to at least some of the writers throughout the Biblical era.
In Egypt it was venerated as a symbol of sunrise. Crocodiles were sometimes reared and cared for in the temples, and embalmed when they died; because they fed on corpses and carrion they were regarded as utterly unclean by the Israelites. These two facts, and esp. their place in pagan worship, could explain why crocodiles are not specifically mentioned. A few scholars, including Bodenheimer, see the Nile crocodile in Ezekiel 29:3ff.; most regard this dragon as fig. of Pharaoh.
Although its average size is smaller today, an occasional individual reaches sixteen ft. and may weigh up to a ton. It is entirely carnivorous, feeding at first on aquatic insects and then fish, later taking birds and mammals, both dead and alive. Crocodiles sometimes become man-eaters but in some parts of Africa this habit does not develop. Throughout their range their numbers are decreasing, mainly because of hunting.
International Standard Bible Encyclopedia (1915)
krok’-o-dil.