- Laura Roman, Britta Denise Hardesty and others
- The Conversation*
How do we save whales and other marine animals from plastic in the ocean?
Our new analysis shows that reducing plastic pollution can prevent the death of beloved marine species.
It is known that more than 700 marine speciesIncluding half of the world’s cetaceans (such as whales and dolphins), all sea turtles, and a third of seabirds ingest plastic.
When animals eat plastic, this can block your digestive system, and cause a slow death and prolonged by starvation.
Sharp pieces of plastic can also perforate the intestinal wall and cause infections and sometimes death. Just one ingested piece of plastic can kill an animal.
Approximately eight million tons of plastic they enter the ocean every year, so solving the problem can seem overwhelming.
How do we reduce the damage that all this plastic does to whales and other marine animals?
Like a hospital overwhelmed with patients, we do a triage (or intervention protocol).
By identifying the elements that are deadly to the most vulnerable species, we can apply solutions that focus on these most deadly elements.
Some plastics are more dangerous than others
In 2016, experts identified four main elements that they considered more lethal for wildlife: fishing waste, plastic bags, balloons, and plastic utensils.
We put these experts’ predictions to the test by evaluating data from 76 published research papers, including 1,328 marine animals (132 cetaceans, 20 seals and sea lions, 515 sea turtles, and 658 seabirds) from 80 species.
We examined which items caused the highest number of deaths in each group, and also the “lethality” of each item (how many deaths per interaction).
We found that the experts got three of the four items correct.
Flexible plastics, such as plastic sheets, bags, and packaging, can cause intestinal obstruction and they were responsible for the highest number of deaths in all groups of animals.
These types of plastic caused the most deaths in cetaceans and sea turtles.
Fishing debris, such as nets, lines, and gear, caused deaths in larger animals, particularly seals and sea lions.
Litter-eating turtles and whales can have a hard time swimming, which can increase the risk of being hit by ships or boats.
In contrast, seals and sea lions don’t eat much plastic, but they can die from eating fish scraps.
Meanwhile, balloons, ropes and rubber were found to be deadly to the smallest fauna. And hard plastics caused the highest number of deaths among seabirds.
Rubber, fishing waste, metal, and latex (including balloons) were the deadliest to birds, with the highest probability of causing death for each recorded intake.
What is the solution?
The most cost-effective way to reduce marine megafauna deaths from plastic ingestion is to target the most lethal elements and prioritize their reduction in the environment.
It is also smart to focus on articles of large plastic, as these can be broken into smaller pieces.
Small debris fragments, such as microplastics and fibers, are a lower priority as they cause significantly fewer megafauna deaths and are more difficult to manage.
Flexible plastics, including plastic bags and packaging, are among the top ten most common items in global surveys on marine debris.
Bans on the use of plastic bags and the inclusion of fees for their use have already been shown to reduce the amount of bags thrown into the environment.
Improving the method of disposing of them locally and creating solutions so that they can be recycled and increased their useful life can also help reduce the amount of plastic garbage.
The lost fishing tackle they are particularly lethal. Fisheries have high rates of loss of their materials: 5.7% of all nets and 29% of all lines are lost annually in commercial fishing.
Introducing minimum standards on higher quality or rugged equipment can reduce losses.
Other measures can contribute, including:
- incentivize the repair of fishing equipment, and create sites in ports to dispose of damaged nets
- penalize or prohibit high-risk fishing activities, where losing equipment is feasible
- and enforce penalties associated with dumping garbage
Disseminate information and educate recreational fishermen to highlight the harmful effects of fishing equipment could also be beneficial.
Balloons, latex, and rubber are rare in the marine environment, but they are disproportionately lethal, especially to turtles and seabirds.
Preventing the intentional release of balloons and their accidental release during events and celebrations would require legislation and a change in public will.
Combining policy change with behavior change campaigns is known to be the most effective in reducing litter off the coast of Australia.
Reducing the amount of plastic sheeting, fishing waste, and latex balloons entering the environment would probably have the best result in directly reducing the mortality of marine megafauna.
* Lauren Roman is a Postdoctoral Researcher, Océanos y AtmSphere, CSIRO (Commonwealth Scientific and Industrial Research Organization) Britta Denise Hardesty is a cientmain research area, Océanos y AtmSphere, CSIROChris Wilcox is a researcher and scientistífico principal, OcTell us and AtmSphere, CSIRO, Qamar Schuyler es cientresearch plan, Océanos y AtmSphere, CSIRO.
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Research Scientist, Oceans and Atmospheres, CSIRO
Senior Principal Research Scientist, CSIRO
Digsmak is a news publisher with over 12 years of reporting experiance; and have published in many industry leading publications and news sites.