Australian Saltwater Crocodile"Single individuals can be found some distance from their usual range (e.g. Japan, islands in the Indian Ocean), as they can travel long distances (over a thousand km) by sea - barnacles have been found on the scales of a few stray individuals. This sea-faring ability probably helps to explain their wide distribution.
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As its name implies, this species has a high tolerance for salinity, being found in brackish water around coastal areas and in rivers. However, it is also present in freshwater rivers, billabongs and swamps. Movement between different habitats occurs between the dry and wet season, and as a result of social status - juveniles are raised in freshwater areas, but eventually sub-adult crocodiles are usually forced out of these areas (used for breeding by dominant, territorial adults), into more marginal and saline areas. Subordinate animals unable to establish a territory in a tidal river system are either killed or forced out into the sea where they move around the coast in search of another river system."
Probably not illegal (though does he have his passport with him?) But if he can mistake an island 80km away for Indonesia 1000km away, there's a good chance he'll kill himself in the attempt.