Fishing nets, fishing lines, and plastic bags, all the things you shouldn’t find in a piece of equipment that was developed to record plankton. Since 1957, the Continuous Plankton Recorder (CPR) has been roaming the open Atlantic with a single goal in mind: sampling and analyzing plankton. The sampling method of the CPR has remained the same since it was first launched. It hangs off the back of container ships and other volunteer barges, and filters water through a roll of silk found on the inside. Once the CPR is hauled back to shore for analysis, researchers unwind the silk and record everything that was caught in the netting, including plastic.
Over the course of 60 years, this three-foot-long, metal torpedo, has covered 6.5 million miles of the North Atlantic. This makes it the longest and most comprehensive record of plastic pollution in the North Atlantic Ocean to date. Using data from the CPR, researchers at the University of Plymouth demonstrated that since 1960, the amount of plastic found in the open ocean has tripled. The most significant rise occurred after the 1990’s, which correlates with the increased rate in production of plastics worldwide.
Although, this study does not provide the whole story. Macroplastics (plastic bags, fishing line, etc.) degrade into microplastics (particles 5.0 mm or less) over time, and these fragments are too small to get caught in the CPR’s silk netting. This implies that the degree of plastic within the oceans is most likely considerably larger than recorded by this study.
Depending on the type of plastic, it can take hundreds of years for the object to break down into microplastics. Plastic bags take around 20 years, while fishing line can take up to 600 years. Deaths of seabirds around the world have been linked to the ingestion of some form of plastic, clogging up their digestive systems. Additionally, as plastic bags appear similar to jellyfish underwater, and sea turtles eat about 75 percent of their body weight in jellyfish per day, more than half of the world’s sea turtles have ingested some sort of plastic.
Today, plastic has been found in animals ranging from whales, fish, sea turtles, tiny crustaceans, birds, and shellfish, accounting for a total of about 700 marine species. Fishing gear often gets discarded or lost at sea as well. Subsequently, over 200 marine species have been reported as impacted by entanglements lost at sea and this could mean the extinction of some endangered species.
The way we use and dispose of plastic facilitates these impacts on wildlife. It has been estimated 4 trillion plastic bags are used annually across the world and only 1% of plastic bags are returned for recycling. Half a billion straws are used every day in the United States. In fact, single-use plastic products in general seldom reach landfills nor are they recycled. It has been estimated that 32% of the 78 million tons of plastic packaging produced annually is left to flow into our beaches and oceans. This is the equivalent of pouring a garbage truck full of plastic into the ocean every minute.
The CPR has yet to complete its record of the last decade (2010-2020) to determine whether or not we are continuing on the current trend of exponential growth in plastic pollution within the Northern Atlantic Ocean. Presently the trend remains but for this next decade we must all remember that these materials do not disappear, they just simply persist elsewhere. This ongoing study sheds light on the importance of consuming less and working toward actions to reduce and improve plastic waste as a whole.
Article by Tatiana Eaves
- Ocean plastic: Kevin Krejci from Near the Pacific Ocean, USA [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]
- Microplastics: Raceforwater [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)]