Plastic waste is building up around the world and creating quite a problem. These plastics are a major contributor to marine pollution, entanglement and ingestion incidents that marine organisms are often subject to. Sea turtles are one of the few organisms that face this problem in both their terrestrial and aquatic environments.
One area of great concern is within the Pacific Ocean. The Great Pacific Garbage Patch has been estimated to be anywhere from the size of France to half the size of Africa. The garbage making up this patch gradually became entrained into the Pacific gyre and then accumulated in the center of this large circular current where it formed this “plastic island”. In fact, the world’s gyres are estimated to hold 73.9 million pounds of plastics. These gyres are often where sea turtle hatchlings spend the majority of their juvenile lives.
The grave effects of marine debris on loggerhead hatchings were recently published by the Chelonian Research Foundation, which found that hatchlings did not avoid contact with marine debris and usually could not escape from simple items like drinking cups and containers, as hatchlings lack the ability to crawl backwards.
At first glance, much of the plastic inhabiting the ocean is undetectable, but under greater scrutiny it was found to lie beneath the ocean’s surface and consist mostly of microplastics (<5mm). These microplastics may do as much harm as the larger plastics that marine animals, like sea turtles and albatrosses, become entangled in or ingest.
Microplastics can be ingested by many types of fish that are at the bottom of the food chain. In fact, fish in the North Pacific Ocean ingest plastic at a rate of roughly 12,000 to 24,000 tons per year, according to a study by Scripps in 2009. This plastic slowly works its way up the food chain, until it gets to the top where we are. Plastics also introduce more hard surfaces in the sea where contaminants and non-endemic species can bind to and use them as a method of transportation.
All of these issues point towards the fact that we need to make a greater effort to reduce, reuse, and recycle our waste!
For more information:
Triessnig, P., A.Roetzer and M. Stachowitsch. 2012. Beach Condition and Marine Debris: New Hurdles for Sea Turtle Hatchling Survival. Chelonian Conservation and Biology. 11(1):68-77.