OceanOmics assesses marine biodiversity along Australia’s southwest coast

Ocean Discovery and Restoration

The expedition, which covered some 1000 kilometres across Wagyl Kaip and Wudjari sea country from Israelite Bay to Albany, Western Australia was part of a larger two-year sampling campaign that began in 2022, to conduct an eDNA based survey of marine vertebrates.

OceanOmics scientists conducted repeat sampling of previous collection sites throughout the region, which will enable them to compare any changes in the eDNA dataset over time.

To date the OceanOmics team has collected 3809 eDNA samples from its expeditions over the past two years.

The resulting eDNA data will be used to inform draft guidelines on the application of eDNA to monitor biodiversity in Australian Marine Parks as part of the Parks Australia’s Ocean Discovery and Restoration Program.

Marine vertebrate hotspots

In addition to collecting baseline information about the region, Minderoo OceanOmics and Ocean Conservation researchers in collaboration with Cetacean Research Centre Western Australia (CETREC WA) are also working to identify marine vertebrate hotspots in the Bremer Marine Park, which is one of 62 Australian Commonwealth Marine Parks, along with neighbouring canyons, using eDNA data and marine mammal surveys.

Testing new technology

The expedition gave OceanOmics scientists an opportunity to conduct the first field-based deployments of an in-situ water sampling and filtration device, Ascension, developed by Ocean Diagnostics, Inc in a 2022 partnership with the OceanOmics team.

Ascension is a tethered sampling instrument capable of collecting up to seven filtered samples directly underwater down to a maximum depth of 400 metres while logging environmental data such as water temperature, depth, flow rate, and total volume filtered for each sample. Field validation of automated samplers such as this are fundamental to proving the eDNA biomonitoring can be achieved on a large scale.

New species discovery

On the voyage, the OceanOmics team also collaborated with researchers from the Western Australian Museum to conduct a focused biodiversity discovery sampling campaign in the eastern Recherche Archipelago.

Bay of Isles, Recherche Archipelago Nature Reserve is comprised of more than 100 islands and over 1200 ‘obstacles to shipping’ stretching in a ribbon running over 230 kilometres from Esperance to Israelite Bay. These islands are remote and seldom visited by specialist scientists, making them a potential hotspot for unrecognised marine diversity.

Western Australian Museum researchers were exploring on behalf of Bush Blitz, Australia’s largest biodiversity discovery program, and used a range of tools including cage diving on SCUBA, trapping, angling, box trawl and netting to collect marine fishes, molluscs and crustacea in search of species that are new to science and new species records for this relatively undocumented region.

This has provided a unique opportunity for OceanOmics scientists to collect high quality tissue samples from the expertly identified museum specimens. The researchers will perform whole genome sequencing on these samples and include this fauna in openly accessible reference sequence databases.

This partnership also represents a valuable opportunity to combine traditional collection methods with eDNA sampling to extend the potential for biodiversity discovery and improve our understanding of how unique marine fauna are distributed across the region.