The impact on the seabed of large bulk carriers and their enormous anchors is the missing body of knowledge when it comes to assessing damage to marine ecosystems, a University of Wollongong researcher said.
Allison Broad said while studies had looked at the impact of recreational boaters' anchors, larger vessels such as those that anchor off Wollongong could pose a more significant threat to seabed life.
Ms Broad and Professor Andy Davis from UOW's School of Earth Atmospheric and Life Sciences (SEALS), along with Dr Matthew Lees from the NSW Department of Primary Industries, have published a paper on anchor scour in the journal Marine Pollution Bulletin, examining existing work on the subject.
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"Most research had focused on recreational boating impacts in shallow waters, with no studies examining the effect of anchoring by large bulk carrier and cargo ships, such as those off Wollongong, on temperate seabed environments," Mr Broad said.
"This represents a significant knowledge gap in our understanding of how this activity affects our local reefs, which is what my PhD research is now focusing on.
"This is the first time that the impact of anchor scour has been examined across a range of habitats, and the evidence so far shows that the impact is negative for seabed environments, but further investigation is needed to understand how to best manage this disturbance."
Ms Broad said seabed environments provided a foundation for much of the life under the sea, establishing "ecosystem engineers" such as seagrasses, kelp, sponges and corals, which support other marine life.
Most research had focused on recreational boating (not) the effect of anchoring by large bulk carrier and cargo ships, such as those off WollongongAllison Broad
She said anchor scour is one pressure on the marine environment that could be better and more easily managed - developing a sustainable framework for how ships can co-exist with ocean health and conservation.
"We must chart a course to more sustainable anchoring practices, which enable recreation and trade [but] not at the expense of our ocean environment," Ms Broad said.
"Failure to recognise and manage anchor scour activities will ultimately risk the diversity of species in the seabed environments exposed to anchoring."