High tech equipment collecting data beneath the waves

Wave, current, sonar and camera equipment has been deployed underwater to allow researchers to track sediment flow in and around Cockburn Sound as part of a project which is expected to improve sand nourishment.

Research Fellow Dr Michael Cuttler, from The University of Western Australia’s Oceans Institute, said the research team had set up the high-tech instrument suites during dive trips to three sites.

“At each site, we have the same instrument packages which are designed to measure sediment transport,” Dr Cuttler said.

“They include acoustic instruments to measure waves and currents, and a three-dimensional scanning sonar and custom camera system to map and track seabed morphology.

“The instruments take measurements throughout the day and have already captured significant storm events this winter.”

The equipment is mounted on frames that are attached to steel poles which are fixed to the sea floor.

Dr Cuttler said the systems work to track how and where the sediment moves.

“A lot of our coastal processes work is focused on understanding the beach dynamics – are they accreting or eroding and under what conditions,” Dr Cuttler said.

Dr Cuttler said one of the key knowledge gaps researchers had been trying to fill was sediment transport from the offshore source to the beach.

“Some of the applications for this work is understanding the potential beneficial reuse of dredge material,” Dr Cuttler said.

“So, if they have excess material and want to use it for beach nourishment, where would be the best place to put it and then how long could we expect for that material to move onshore to act as sediment nourishment for the beach.

“One thought is that if you can understand the sediment transport pathways, you can optimise that nourishment, so it continually feeds the beach using natural processes.”

The Coastal Processes project, led by UWA’s Dr Jeff Hansen, is part of the WAMSI Westport Marine Science Program.

The equipment has been deployed three times since the start of the year during different seasons and a final deployment is planned for early 2024.





Cards, cocktails in yurts and community chats help inspire climate action

As a climate change ecologist and passionate science communicator, Professor Gretta Pecl knows the challenges of talking about dire threats to the oceans and species extinction, without people feel overwhelmed and ‘switching off’.

Professor Pecl, the Director of the Centre for Marine Socioecology at The University of Tasmania, and a researcher at the Institute for Marine and Antarctic Studies, gave the plenary presentation recently at the International Conference and Workshop on Lobster (and Crab) Biology and Management in Fremantle. The presentation was on ‘Fisheries in a warming world and changing ocean: What’s in store and what’s needed to ensure a thriving future?’.

The Western Australian Marine Science Institution was a conference sponsor.

“People need to understand the oceans; how they are changing and will change and one of the best things we can do is share stories of successful adaption programs,” Professor Pecl said.

She told delegates there seemed to be an increased acknowledgement of what was happening globally.

“In 2010 we surveyed fishers and 80 percent didn’t think climate change was happening,” Professor Pecl said.

“If we surveyed the same people now, I think it would be a very different response.”

Professor Pecl is a regular presenter at conferences but told delegates creating a two-way dialogue in smaller, informal venues was just as important. She talks with people about climate change and broader science issues in podcasts, over ecology themed playing cards and even while sharing cocktails at science events in yurts (round tent-like dwellings).

“I have toured pubs doing community question and answers and people are curious and want to know more.

Professor Gretta Pecl speaks in a pub at the ECCW05 in Bergen Norway

Professor Gretta Pecl speaks in a pub at the 5th International Symposium on the Effects of Climate Change on the World’s Ocean in Bergen Norway. Photo: Dr Jenny Shaw

“We also collaborate with media experts and psychologists because as humans we can be hard wired to not believe in climate change or to find it overwhelming to the point where it limits our capacity to take action.”

The evidence of climate change impacts is worrying. Professor Pecl said the sea surface temperatures hit 38 degrees in Florida Keys this July and heat-stressed corals began bleaching.

There were marine heatwaves on the Great Barrier Reef in Australia in 2016, 2017, 2020 and 2022.

“Reefs are resilient and can recover but the recovery period needs to be 10 to 20 years.

“They can’t be bleached year in, year out.

“Reducing other human caused pressures on reefs can help improve their natural adaptive capacity and for kelp forests, transplantation of heat tolerant phenotypes is useful.

“But without carbon emissions reduction these systems are still at risk.

“Five percent of species are at risk of extinction from 2 degrees of warming alone and that jumps to 16 percent at 4.3 degrees warming.

“The loss of biodiversity is not only an environmental issue but a developmental, economic, security, social and moral issue as well,” Professor Pecl said.

“Although oceans are changing fast, everyone is looking to the ocean for solutions.

“The ocean contains 50 times as much carbon as the atmosphere and acts as a biotic and abiotic thermostat by absorbing and releasing carbon dioxide and heat.”

Professor Pecl told conference delegates seafood had a relatively low carbon footprint compared to land base sources of food protein such as beef, lamb and cheese. Wild catch seafood rated better than aquaculture.

She said there had been a high level of coordination and collaboration in the research and industry sectors across Australia for more than 15 years and there was a well-networked research community.

“We can’t continue into a ‘business as usual’ future but it is possible to show a positive vision and create a mobilising narrative that supports action on climate change,” Professor Pecl said.

Project to predict and manage marine heatwave threats

Scientific experts from around Australia will work together on a major new UN-endorsed research project that aims to better forecast and respond to extreme marine heatwaves, as warnings mount that the devastating events will become more frequent and severe.

Lead scientist Professor Nicole Jones, from The University of Western Australia, said the project would uncover new data as well as gather historical information.

“These marine heatwaves have had a serious ecological and economic impact on the state in recent decades including the loss of coral, kelp and seagrass,” Professor Jones said.

“We have seen an impact on fisheries and there are also long-term changes to the function of the various ecosystems.”

The Western Australian Marine Science Institution will manage the project, ‘Advancing predictions of Western Australian marine heatwaves and impacts on marine ecosystems’ with funding from the Department of Jobs, Tourism, Science and Innovation. The project was recently endorsed as part of the UN Decade of Ocean Science for Sustainable Development 2021-2030.

The multi-disciplinary project team of 26 includes researchers in oceanography, marine ecology, atmospheric science and data science.

“Our key aim is to develop tools to efficiently create seasonal forecasts of ocean temperature and the associated habitat response to marine heatwave events for the coastal ocean. This information can be used to manage responses to future marine heatwave events,” Professor Jones said.

The project also aims to identify areas most at risk from marine heatwaves and those that are more likely to be resilient.

WAMSI Chief Executive Officer Dr Luke Twomey said the four-year project was an important one for WA.

“This will help the WA Government agencies make management decisions for the marine environment threatened by marine heatwaves,” Dr Twomey said.

Project scientists come from organisations including Bureau of Meteorology, Curtin University, Department of Biodiversity, Conservation and Attractions, Department of Primary Industries and Regional Development, Edith Cowan University, Murdoch University, and UWA.

The project is also funded by the Indian Ocean Marine Research Centre Strategic Infrastructure Investment Fund, the Jock Clough Marine Foundation and Fisheries Research and Development Corporation.


Coral reefs vital for ocean life

A quarter of all marine species depends on coral reefs but these vital parts of the oceans’ ecosystem are at risk from acidification, pollution, over-fishing and rising water temperatures.

The University of Western Australia’s PhD candidate Josh Bonesso spoke to high school students recently about the significance of coral reefs, as part of the Western Australian Marine Science Institution’s Thinking Blue outreach program. Josh was a finalist in the Student Scientist of the Year category in this year’s Premier’s Science Awards for his innovative research on coral reef islands. He’s also a keen science communicator.

“Coral reefs are nursery grounds for fish, they’re important too for megafauna and the building of coral reef islands that provide nesting areas for many species of seabirds and turtles,” Josh said.

“So, while coral reefs aren’t a large component of the ocean, about 25 percent of marine species rely on them directly and indirectly.”

Josh explained to the Year 12 students how coral reefs formed over thousands of years but that higher-than-normal temperatures and storm events caused by climate change threatened the survival of many coral varieties, particularly fragile branching corals. Mound corals were generally more resilient, but Josh said it was important for reefs not to become homogenous.

“At 34 degrees a species of branching coral, Acropora aspera, exerts a stress response and experiences bleaching.

“We know less about how these corals cope with stress at temperatures below bleaching, at around 32 degrees, and how this impacts their recovery from injury following storm events.”

“But experiments have been done in tanks at that lower temperature where the tops of coral branches are snipped off, to replicate storm damage, and they haven’t grown back,” Josh said.

Thinking Blue is WAMSI’s education outreach program which is designed to educate students about marine science and inspire them to do further studies in the field.

Josh is a PhD candidate at UWA’s Oceans Institute. He did his undergraduate science degree at La Trobe University and initially studied alpine and conservation ecology. But he told the students after a field trip to the Heron Island Research Station on the Great Barrier Reef, he ‘fell in love with coral reefs’.

You can watch Josh’s lecture here.

Fly larvae offers hope for future food security

Insects could be part of the solution to future global food security pressures, according to an aquaculture researcher looking at black soldier flies as a potential fish feed source.

PhD candidate Isobel Sewell, from The University of Western Australia, told students in a Thinking Blue lecture there was growing pressure on wild stocks from overfishing.

This, combined with the world’s population forecast to exceed nine billion by 2050, meant there was an increased focus on aquaculture as a sustainable alternative.

Thinking Blue is WAMSI’s school outreach program which gives students in Years 11 and 12 a chance to hear from marine scientists doing innovative research. It also aims to inspire school leavers to study marine science.

“The main question is, where will we find enough food for another one billion people and we think black soldier flies and their larvae could help,” Isobel said.

“Aquaculture is the most rapidly growing food production sector globally and there’s a lot of research looking at the feed given to fish that are reared in tanks and sea pens.”

“I am running trials at UWA with barramundi and marron to see how experimental diets containing black soldier fly larvae compare to a more traditional aquaculture diet, which typically contains wild-caught fish as a protein source.”

“For black soldier fly larvae to be considered a suitable alternative protein source, we need to ensure fish growth is promoted whilst still maintaining fish well-being.”

“So far, we have found barramundi fed the insect-based food are growing successfully and tests on their biological parameters, such as blood health, are within healthy parameters,” Isobel said.

She said the principal behind the experiment was to try to find ways of ensuring aquaculture fitted into the black soldier fly circular economy model.

“The three principles of the circular economy are to design out waste and pollution, to keep products and materials in use and to regenerate natural systems.”

Isobel said the ingredients for traditional barramundi aquaculture fish food was about 40 per cent plant dry matter, 30 per cent land animals, 15 per cent marine animals, 7 per cent land animal oil, and 1 per cent marine animal oil.

“There has been research on using more protein-rich plants such as soybean, but results showed they had the potential to cause inflammation of the fishes’ digestive tract.”

She said fish was an important food source for humans and had significant health benefits and there were concerns about the world’s growing population being able to nutritionally sustain itself without putting more pressure on ocean or land resources.

“Food insecurity affects 820 million people around the world, which is the equivalent of the combined populations of Canada, the United States of America and the European Union,” Isobel said.

Isobel told the students she had improved her experience during her studies by volunteering on projects including looking at plastic abundance on Albany beaches, tagging turtles on Barrow Island as part of a project investigating light pollution and working on a coral nursery in the Seychelles.

Find a link to Isobel’s talk here.