Over 1,000 sharks and stingrays have been trapped in plastic floating around the ocean over the past ten years, according to a new study.
Over the past 10 years, hundreds of sharks and stingrays have become entangled in plastic waste in the world’s oceans, U.K. researchers said.
University of Exeter scientists stated that plastic had entangled roughly 1,000 animals since 2009, based on their past findings from published studies and reports on Twitter.
According to their new study published in Endangered Species Research, these incidents have involved animals trapped in, lost, or discarded fishing gear, which is also called “ghost gear.”
“Ghost fishing gear appears to be the biggest culprit of entanglement for sharks and rays,” said researcher Kristian Parton.
The study is the first of its kind to use social media reports to help track entanglement, Parton said. The team tracked hashtags including #MarineDebris, #entaglement, #shark, and #Ghostfishing, among others, and scrolled back to find the very first time each hashtag had been used for a report of a shark or ray entangled in plastic. The first Twitter report was in 2009.
Due to the fact, these were only reported incidents shared on social media the team’s estimates may be low-balling the actual figure.
The researchers also looked at scientific literature written on the topic for their research. Parton said the team “found twice the number of entanglement reports on Twitter” than was in the scientific literature over the last 70 plus years, despite the Twitter data was covering a much smaller time period.
The team argued that the true number of times that sharks and rays have been entangled in plastic is likely much higher than 1,000, in part because of the imperfections of Twitter data collection and because only a few scientific studies have focused on this.
Parton acknowledged that not every tweet provided equal information, as not every tweet contained photos or videos.
Through Twitter, they identified some species that had never been recorded in scientific studies before as becoming entangled in plastic, such as great white sharks and whale sharks.
“We have set up an online entanglement report form in collaboration with the shark trust, in the hope that citizen scientists can document (shark and ray) entanglement,” Parton said. “This will help us compile more data on the issue, and help us accurately identify worst impacted species and in particular ocean areas.”
While the team argues these entanglements were a major animal welfare concern, they were a “far lesser threat” to sharks and rays than commercial fishing. And entanglement is only one way that plastics floating in the oceans could affect marine animals.
In February 2018, a separate study found that microplastic pollution and associated toxins threatened filter-feeding animals such as manta rays, whale sharks and baleen whales.
The researchers stressed these microplastics can be accidentally ingested when these creatures swallow thousands of cubic meters of water in an effort to capture small prey including plankton.
