The Australian Academy of Science has called for an overhaul of the nation’s approach to studying plastic pollution, warning there is an over-reliance on volunteers and a lack of consistent data to document the “astronomical” problem.

About three-quarters of rubbish along Australia’s coast is plastic, posing a threat to more than 690 marine animals including turtles and seabirds. CSIRO researchers believe 43% of short-tailed shearwater birds in eastern Australia have plastic in their gut.

There have been major surveys of plastic pollution on beaches, including the UNSW-led Australian Marine Debris Initiative and the CSIRO’s international research partnership. But the academy is calling for more regular surveys that have a consistent approach and are collated in a national plastic pollution database.

“To stop pollution effectively you need to know its source, and knowing what leaks into the environment and its origins is critical for that,” said Prof Chennupati Jagadish, the president of the Australian Academy of Science.

“Just as we have national monitoring systems for emissions, outdoor air quality, and wastewater for drugs or Covid, it should be possible to identify some points to measure the amount of plastics entering our waterways to get a more complete and regular picture.”

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Most marine debris surveys are heavily reliant on citizen scientists. A recent CSIRO plastic pollution survey was assisted by 3,500 volunteers while a UNSW-led project called on 150,000 volunteers. The National Litter Index and AusMap are also reliant on citizen scientists.

“Citizen science is valuable and we are glad for the above initiatives,” Chennupati said. “However, better data arrangements are required that would allow for standard methodology, collection and harmonisation.

“They would also add more resilience, meaning we’re not reliant upon the goodwill and the consistent availability of volunteers.”

Colleen Hughson, the co-leader of BeachPatrol 3280-3284, a volunteer group that cleans beaches between Warrnambool and Port Fairy on Victoria’s western coast, has spent years maintaining a database of plastic pollution.

Hughson and her team have collected almost half-a-million items of plastic and marine debris, weighing a total 6.5 tonnes. This includes 321,000 pieces of hard plastic, 20,000 bottle lids, 40,000 fishing ropes in nets. The group have also collected foreign-labelled drink bottles, spray cans, plastic forks, fluorescent light tubes and cigarette tins.

Hughson said she was frustrated that years of data collected by her group hadn’t fed into national studies of plastic pollution and marine debris. She said any national database should build on the hard work of volunteers, not replace it.

“We have a good system, we go to the same beaches each day, we document how much time we spent there, how long we walked for, how many kilograms [of marine debris] we found, how many items we found, what the items were,” Hughson said.

“Who do we show our data to? Who is going to do something? No one. And that’s one of the big issues that we find. We don’t want to be volunteers doing the work, we actually want to see results.”

Hughson said a lot of the existing data reflected what was being washed into urban waterways, as that is where many volunteers live.

“We have these amazing ocean beaches that are not impacted by human littering as not many people visit them, so we’re seeing what’s being washed ashore,” Hughson said. “We’re getting lost commercial fishing gear and international shipping rubbish.

“The consistency of going back to the beach every day, or every second day, gives you a really strong sense of what the problem plastics are.”