Researchers measured the amount of plastic off the coast of Indonesia divers also collected vomit and feces samples and measured the plastics in them during the wet season manta rays consume 63 pieces of plastic an hour
Humans produce 254 trillion tons of trash each year, much of which ends up in the ocean.
Every year, some 5.25 trillion new pieces of plastic debris are thrown into the ocean, including nearly 564 billion water bottles and more than 500 billion plastic bags.
Indonesia is the second largest contributor of ocean plastics in the word and a group of researchers decided to study the effects of all that sea plastic on two of the most famous residents of Indonesia's oceans: the manta ray and whale shark.
Between January 2016 and February 2018, the team took samples from the waters around one stretch of coastline in south-central Indonesia where rays and whale sharks often feed.
The researchers dragged a fine mesh net through these waters, simulating how rays and whale sharks slowly swim with their mouths open to catch plankton.
Based on the amount of plastic debris caught in these nets, the researchers were able to calculate the amount of plastic a ray or whale shark would ingest using the average volume of water they pass through their open mouths while feeding.
During the country’s wet season, they calculated that rays could ingest as much as 63 pieces of plastic per hour.
In the dry season, rays would take in around four pieces per hour.
To check their findings, the team also worked with local SCUBA divers to search for manta ray vomit and feces samples, the later of which they collected in ‘poo tubes.’
There was an average of 26 pieces of plastic in the manta ray feces and 66 pieces in the vomit samples the researchers were able to get.
‘In other organisms, including fish, we know that exposure to some of the plastic associated pollutants can disrupt the regular functioning of the endocrine system, the system responsible for controlling growth and reproduction,’ co-author Elitza Germanov told Gizmodo.
‘As threatened species, neither manta rays nor whale sharks can afford to have any dips in reproductive rates.’
HOW DAMAGING ARE PLASTIC BOTTLES?
Of 30 billion plastic bottles used by UK households each year, only 57 per cent are currently recycled.
With half of these going to landfill, half of all plastic bottles that are recycled go to waste.
Around 700,000 plastic bottles a day end up as litter.
This is largely due to plastic wrapping around bottles that are non-recyclable.
Bottles are a major contributor to the increasing amount of plastic waste in the world's oceans.
Researchers warned eight million tonnes of plastics currently find their way into the ocean every year - the equivalent of one truckload every minute.
The amount of plastic rubbish in the world's oceans will outweigh fish by 2050 unless the world takes drastic action to further recycle, a report released in 2016 revealed.
At current rates, this will worsen to four truckloads per minute in 2050 and outstrip native life to become the largest mass inhabiting the oceans.
An overwhelming 95 per cent of plastic packaging - worth £65 - £92billion - is lost to the economy after a single use, the Ellen MacArthur Foundation report stated.
And available research estimates that there are more than 150 million tonnes of plastics in the ocean today.
So much plastic is dumped into the sea each year that it would fill five carrier bags for every foot of coastline on the planet, scientists have warned.
More than half of the plastic waste that flows into the oceans comes from just five countries: China, Indonesia, Philippines, Vietnam and Sri Lanka.
The only industrialized western country on the list of top 20 plastic polluters is the United States at No. 20.
The US and Europe are not mismanaging their collected waste, so the plastic trash coming from those countries is due to litter, researchers said.
While China is responsible for 2.4 million tons of plastic that makes its way into the ocean, nearly 28 percent of the world total, the United States contributes just 77,000 tons, which is less than one percent, according to the study published in the journal Science.