Coral Sea, Australia
SOUTH PACIFIC OCEAN: 10 OCT – 14th NOV 2025
The Ocean Census joined forces with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) for a 35-day expedition, on CSIRO research vessel (RV) Investigator, to investigate benthic marine life in the southern and eastern Coral Sea Marine Park, focusing on two of the parks three key ecological features: the reefs of the Marion Plateau and the Tasmantid Seamount Chain (200-3600m).
Mission GUIDE
The Coral Sea expedition is the first modern deep-water investigation of marine life found on the extinct volcanic peaks of the northern Tasmantid Seamount Chain which rise over 3000m from the seabed and the offshore Kenn Plateau making this expedition critical for understanding of regional biodiversity.
CSIRO will deploy a suite of gear types to survey marine life, including towed camera, eDNA sampler, CTDs, trawls, and sleds.
The faunal biodiversity information generated will be used to determine how biodiversity varies across these key ecological features and between the bioregions within the marine park. The information will also be used to examine endemicity levels in fishes and key invertebrate groups and assess whether seamounts and atolls support greater levels of local endemicity than the continental slope and offshore plateaus.
Additionally, the project will provide new detailed seabed mapping, particularly on the Marion Plateau where data are currently limited.
The results of this project will contribute to primary outcomes of the Australian Marine Parks’ Marine Science Program, by increasing understanding of marine park values, through detailed data on benthic communities present in the Coral Sea Marine Park (CSMP) and enabling improved evidence-based decision making by addressing key priorities established by Parks Australia for the CSMP. The most significant outcome for Parks Australia will be the provision of vital data on the benthic communities of the Special Purpose Zones and the Tasmantid Seamount Chain for inclusion in the 2028 Coral Sea Marine Park Management Plan (see current plan).
Mission facts
Dates
10th October – 14th November 2025
Duration
35 days
Location
Coral Sea, Australia
Type
Partner
Image credits
CSIRO/Frederique Olivier
Mission brief
Mission Objectives
Describe the benthic faunal biodiversity (fishes and key macroinvertebrate groups) from biological communities around atolls, seamounts, offshore plateaus, and the continental slope of the southern and eastern CSMP in the major bathomes.
Quantify the level of endemism of fishes and key macroinvertebrate groups in the southern and eastern CSMP.
Contribute to the AusSeabed project by maximising new multibeam coverage to create detailed maps of seafloor topography and morphological habitat types of the Marion Plateau, Tasmantid Seamount Chain and Kenn Plateau.
Test predictive models linking biogeophysical parameters and deep-water benthic biodiversity.
Collect specimens for species identification and descriptions, and to archive specimens in biological collections, including tissue samples to build marine invertebrate and fish genetic reference libraries for the Coral Sea.
Conduct a detailed environmental DNA analysis across the study region in parallel with traditional biodiversity survey methods.
Compare the faunal data from each sampling method to determine the most appropriate for addressing research questions, in particular extractive vs. non-extractive methods.
Compare the biogeographical relationships of the benthic fauna found in the CSMP to other Australian bioregions.
Use population genomic methods to assess connectivity, diversity, and source and sink relationships between benthic invertebrate and fish species across the seamounts and atolls of the Tasmantid Seamount Chain to inform management decisions.
Mission Partners
Expedition
Highlights
News
This research is supported by a grant of sea time on RV Investigator from the CSIRO Marine National Facility. The research is supported by Parks Australia, Bush Blitz and The Nippon Foundation-Nekton Ocean Census.’
Image Credits: CSIRO, Frederique Olivier, Benjamin Healley
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