Updated: Dec 27, 2020
As it turns out, plastic is not so fantastic, especially for marine wildlife. Plastic pollution, which was once an issue that posed little threat, has evolved into a massive environmental undertaking. It is estimated that there are 5.25 trillion pieces of plastic material circulating in the ocean. Of that mass, 269,000 tons float on the surface, while some four billion plastic microfibers per square kilometer litter the deep sea.
Some species of marine life are struggling more than others to live in ecosystems filled with plastic; sea turtles being one of the more vulnerable and sensitive species. Sea turtles are very mobile creatures, with vast migration patterns, specific mating behavior, and delicate lifestyles, making them more susceptible to environmental stressors.
Nearly all sea turtle species are considered endangered. This means that their populations are continuing to decline. Factors like climate change, being subjected to fishing bycatch, hunting and poaching, are all responsible for their decline. Plastic pollution, however, is their latest and possibly greatest threat.
In addition, climate change makes harder for sea turtles to prosper. Climate change increases storm frequency and severity, which may disrupt migration patterns and beach habitat. Warming sea temperatures will have effects on currents, which are likely to introduce sea turtles to new predators and stressors.
Sea turtles are affected by plastic pollution in 3 main ways.
Plastic debris such as plastic bags appear very familiar to sea turtles. Ocean current pushes plastic bags, causing them to sway and appear much like jellyfish, which are a staple in the diet of sea turtles.
Things such as plastic fishing line or netting are easily mistaken for seaweed, another main food item for sea turtles. Sea turtles are unable to digest plastic materials, and often will fill their stomachs up with plastics, causing them to feel full, and eventually they will perish due to starvation. Research conducted by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the University of the Sunshine Coast (USC) found that a turtle had a 22% chance of dying if it ate just one piece of plastic.
If sea turtles do not consume plastic debris, they are still at risk of becoming entangled in old fishing equipment and netting. Entanglement often leads to death, as sea turtles need to reach the ocean surface occasionally to breath. If they become entangled and submerged under water, they will die of suffocation.
When this is not the case, sea turtles, even those who manage to free themselves from entanglement, are likely to suffer some sort of injury. The injuries place them in a more vulnerable position, often attracting predators. Injuries also affect their ability to reproduce, and could cause them to die due to infections or non-survivable injuries.
3. Habitat Destruction
Sea turtles utilize various habitats for resting, hunting for food, and reproducing. Plastic pollution, however, creates an environment that may block out sunlight, which inhibits plant growth in habitats where sea turtles may usually collect food. This, along with other environmental stressors, may cause sea turtles to venture further away from their usual territories, making them a target for predators.
Plastic pollution also creates a dangerous environment for them to thrive, as many plastics have hard edges, and litter the ocean floor, where they enjoy spending time.
In conclusion, sea turtles are valuable marine species who are sensitive to environmental changes. The three main ways they are affected by marine plastic pollution is through ingestion, entanglement, and habitat destruction. Sea turtles are incredible creatures, with vast migration patterns, and are one of the most adored marine species. They have many threats, including poaching, climate change, and now, plastic pollution. To protect sea turtles, supporting organizations dedicated to ocean conservation is a great way to start!