The Saltwater Crocodile, Crocodylus porosus Schneider, 1801, in the Kimberley coastal region

摘要

The Australian Saltwater Crocodile, Crocodylus porosus, is an iconic species of the Kimberley region of Western Australia. Biogeographically, it is distributed in the Indo-Pacific region and extends to northern Australia, with Australia representing the southernmost range of the species. In Western Australia C. porosus now extends to Exmouth Gulf. In the Kimberley region, C. porosus is found in most of the major river systems and coastal waterways, with the largest populations in the rivers draining into Cambridge Gulf, and the Prince Regent and Roe River systems. The Kimberly region presents a number of coastlines to the Saltwater Crocodile. In the Cambridge Gulf and King Sound, there are mangrove-fringed or mangrove inhabited tidal flats and tidal creeks, that pass landwards into savannah flats, providing crocodiles with a landscape and seascape for feeding, basking and nesting. The Kimberley Coast is dominantly rocky coasts, rocky ravines/ embayments, sediment-filled valleys with mangroves and tidal creeks, that generally do not pass into savannah flats, and areas for nesting are limited. Since the 1970s when the species was protected, the depleted C. porosus populations have recovered across northern Australia. Monitoring shows large geographical variations in current population abundance between and within rivers of the Northern Territory, Queensland and Western Australia, and modelling shows strong support for linkage to the ratio of total area of favourable wetland vegetation (Melaleuca, grass and sedge) to total catchment area, rainfall seasonality, and other climate parameters.