Invertebrate diversity in the deep Great Australian Bight (200–5000 m)

Abstract

Background: The Great Australian Bight (GAB) comprises the majority of Australia's southern coastline, but to date its deep water fauna has remained almost unknown. Recent issuing of oil and gas leases in the region has highlighted this lack of baseline biological data and established a pressing need to characterise benthic abyssal fauna. Methods: From 2013 to 2017, six large-scale systematic surveys of the GAB were conducted from 200 to 5000 m depth, constituting the deepest systematic biological sampling in Australia. Sampling was conducted on soft sediment and hard substrates, both at predetermined depth intervals along north-south transect lines and at sites of interest identified by multibeam sonar. Results: A total of 66,721 invertebrate specimens were collected, comprising 1267 species, with 401 species (32%) new to science. In addition to the novelty of the fauna, there was a high degree of rarity, with 31% of species known only from single specimens. Conclusions: In this paper, we provide an annotated checklist of the benthic invertebrate fauna of the deep GAB, supplemented with colour photos of live specimens and commentary on taxonomy, diversity and distributions. This work represents an important addition to knowledge of Australia's deep sea fauna, and will provide the foundation for further ecological, biogeographical and systematic research.

Hexactinellida from the Perth Canyon, Eastern Indian Ocean, with descriptions of five new species

“…Recent expeditions (e.g. Schlacher et al 2007, Fromont et al 2012, MacIntosh et al 2018) have collected specimens from southeastern Australia, Western Australia and the Great Australian Bight in South Australia respectively. Future expeditions (in 2020) are planned in canyons off north-western and south-western Australia.…”

“…Deeper regions of the vast Australian continental margin remain to be explored. Continuing to identify specimens from existing glass sponge collections and to undertake additional fieldwork will begin to address the gap noted by MacIntosh et al (2018), that deep sea studies on regional and global scales are still too scarce to generalize on the relationships between sampling effort, species distributions and diversity. However, at this time the affinities of the Australian glass sponge fauna are largely Indo-West-Pacific.…”

“…This is the first record of the genus Walteria in the Indian Ocean. Previously it has been recorded in the Western Pacific from Japan to north east of New Zealand and in South Australia at depths of 370-4732 meters (Tabachnick, 2002b;Reiswig & Kelly 2018;MacIntosh et al 2018). Description.…”

Deepwater decapod, stomatopod and lophogastrid Crustacea from Eastern Australia and the Great Australian Bight collected in 2015–2017: preliminary identifications of 191 species

“…For the Great Australian Bight surveys, we acknowledge the funding support of "The Great Australian Bight Research Program", which represents a collaboration between BP, CSIRO, the South Australian Research and Development Institute, the University of Adelaide and Flinders University, and also "The Great Australian Bight Deepwater Marine Program", which is a CSIRO-led research program sponsored by Chevron Australia. The chief investigator on this project was Alan Williams (CSIRO Oceans and Atmosphere), assisted by Hugh MacIntosh (Museums Victoria) and many others (see MacIntosh et al (2018).…”

“…Deepwater decapod, stomatopod and lophogastrid Crustacea Between 2013 and 2017, six surveys (all in conjunction with the oil exploration companies through "The Great Australian Bight Research Program" and "The Great Australian Bight Deepwater Marine Program") systematically targeted the benthic biota of the deep GAB, at depths of 200-4600 m, in order to document the biodiversity of the region before any mining proceeds. This was the first time that the Australian abyssal fauna had been sampled systematically (MacIntosh et al, 2018).…”