New Delhi, June 5 -- Thousands to millions of tonnes of plastic enter the ocean annually, but where they end up is poorly understood.

Scientists have been working to assemble the pieces of the puzzle for years, including estimating the size of the reservoir of plastic on the ocean surface, in the water column and in the deep ocean. However, marine animals are often overlooked.

All animals can be reservoirs of plastic pollution, but to understand just how much ocean plastic pollution is stored in ocean life, we used sea turtles as a case study.

Sea turtles ingest plastic debris of a variety of shapes and sizes, which can include pre-production pellets, foam, plastic bags, sheets, fishing gear and food wrappers. Their ingestion of plast...