The estuarine crocodile (Crocodylus porosus) is a semi-aquatic reptile, living mainly in rivers, mangroves and estuaries. Its geographical range extends more than 10,000 km2 of the South-East Pacific, from East India to Fiji and from southern China to North Australia. Although it spends most of its life in saltwater, it cannot be considered a marine reptile in the same way as a turtle is, for example, because it relies on land for food and water. The results explain why, despite occupying such a large range, species diversification of the estuarine crocodile has not occurred. One satellite-tagged crocodile a 3.84 meter-long male left the Kennedy River and travelled 590 km in 25 days down the west coast of Cape York Peninsula, timing his journey to coincide with a seasonal current system that develops in the Gulf of Carpentaria.