The Australian Government has issued a draft threat abatement plan with strategies to reduce marine debris. The plan specifically targets plastic litter.
It said marine debris, particularly plastic, is harmful to marine wildlife, with impacts caused through entanglement, ingestion and contamination.
The draft threat abatement plan for the impacts of marine debris on vertebrate marine species follows an Australian Senate inquiry on the threat of marine plastic pollution in Australia, which released a report, Toxic tide: the threat of marine plastic, in April 2016.
The draft plan said marine debris impacts have been documented for seabirds, marine turtles, cetaceans, sharks and other Australian marine wildlife, including many species listed as threatened.
The Federal Government has sought public comment on the draft plan and will then release a final plan.
The draft contains six major objectives. It aims to:
• Contribute to the long-term prevention of the incidence of marine debris.
• Identify key species, ecological communities, ecosystems and locations impacted by marine debris for priority action.
• Conduct research to understand and mitigate the impacts of microplastic and plastic debris on marine species and ecological communities.
• Remove existing marine debris.
• Monitor the quantities, origins, types and hazardous chemical contaminants of marine debris, and assess the effectiveness of management arrangements over time for reducing marine debris.
• Increase public understanding of the causes and impacts of harmful marine debris, including microplastic and hazardous chemical contaminants, to generate behaviour change.
The draft, developed by the Department of the Environment and Energy, said a 2016 systematic review of ecological impacts of marine debris found 82% was plastic.
A scientific paper published in Marine Policy last year found fishing gear, balloons and plastic bags were the biggest entanglement threat to marine fauna. Plastic bags and utensils were rated the biggest ingestion risk for seabirds, turtles and marine mammals.
Another scientific paper, published in Environmental science & technology in 2011, found fragmentation of larger plastic items, introduction of small particles used as abrasives in cleaning products, and spillage of plastic powders and pellets in sewage waste were identified as potential routes for entry of microplastics into the environment.
“Ingestion of microplastic provides a potential pathway for the transfer of pollutants, monomers, and plastic additives to organisms with uncertain consequences for their health,” the draft plan said.
It also cited a 2013 scientific report, Marine plastic pollution in waters around Australia: characteristics, concentrations and pathways, published in the journal PloS One, that found marine plastics in Australian waters were predominantly microplastics resulting from the breakdown of larger polyethylene and polypropylene objects.
Mean sea surface plastic concentration was more than 4,000 pieces in each square kilometre and, after incorporating the effect of vertical wind mixing, it increased to nearly 9,000 pieces per square kilometre.
The plan said domestic policies on materials, supply chains, product stewardship, waste management and resource recovery could minimize the volume of debris entering the ocean.
It said "Plastic Free July," an initiative developed by Western Metropolitan Regional Council in Perth, Western Australia, was an example of “effective community-based action aimed at raising awareness of issues associated with single-use disposable plastic.“ The initiative encourages the public to refuse single-use plastic every July, focusing on plastic bags, bottles, takeaway coffee cups and straws.