Soft coral and sea fan (Octocorallia) biodiversity and distribution from a multi-taxon survey (2009–2014) of the shallow tropical Kimberley, Western Australia

WA Museum Records and Supplements | Updated 7 years ago

ABSTRACT – Any assessment of tropical reef ecosystems should extend beyond a hard coral inventory to include soft corals and other sessile benthic organisms. We assessed octocoral assemblages at 177 marine survey stations in the Kimberly region, Western Australia (<30 m depth), to establish species inventories and describe community structures. The 1,174 vouchered specimens yielded a total of 206 Linnean and morphospecies. The overall composition of this fauna was typical for tropical Indo-Pacific shallow water coral reefs. Octocoral communities demonstrated high species heterogeneity across habitats, with strong differences between inshore and offshore, and a latitudinal zonation along the Kimberley inshore. Of the recorded taxa, 45% were exclusively found offshore, 16% inshore and 39% occurred both inshore and offshore. The nearshore Bonaparte Peninsula, the midshelf region and the northern offshore regions were all ‘hotspots’ for soft coral diversity, while the southern offshore regions presented the most distinct species composition. These results have profound implications for conservation strategies relating to these remote benthic habitats.