Dugong Distribution and Relative Density, Northeast Australia

We use a 20-year time series of systematic aerial surveys of dugong (Dugong dugong) abundance to create spatially-explicit models of dugong distribution and relative density at the scale of the coastal waters of northeast Australia (136,000 km2). We interpolated the corrected data at the scale of 2 km * 2 km planning units using geostatistics. Planning units were classified as low (1), medium (2), high (3) and very high (4) dugong density on the basis of the relative density of dugongs estimated from the models and a frequency analysis.