Sharks and sea turtles rely on each other to maintain a healthy population. Although the recovering population of green turtle provides more prey for tiger sharks, it also puts more pressure on the abundance of seagrass, which is the primary food source of turtles. The declining population of sharks can lead to the destruction of seagrass. Sea turtles, pollution, changes in water quality and dredging pose a risk to seagrasses. The loss of sharks can also cause the seagrass ecosystems to collapse.
Many sea turtle conservation programs have been launched in the recent years. These efforts have helped recover the population of sea turtles, but they’ve failed to address another problem. Shark populations are declining due to overfishing and this is creating an imbalance in the oceans of the world. Maintaining the delicate food chain balance should involve preserving turtles, seagrasses and sharks at the same time. Failure to do so could lead to an ecosystem collapse. This is because a healthy ecosystem requires a stable population at every level of the food chain.
Conservation efforts to restoring the populations of sea turtle have made people realize how overfishing large sharks is affecting seagrasses. Green turtles forage among seagrass meadows and their diet consists mostly of seagrasses, seaweed and algae. Their beak has finely serrated edges that allow them to scrape off algae and tear seagrasses. Other species like the Olive Ridley are omnivores and eat a variety of plants and animals, including algae, shrimp, crabs, lobster, fish, urchins and jellies.
Once turtles make their way to the ocean, they can be prey for other animals such as large fish, orcas and sharks, especially tiger sharks. Healthy populations of tiger sharks can help keep the populations of turtles stable so that they don’t demolish entire meadows before the seagrasses are able to grow back. Seagrass meadows are one of the most valuable ecosystems in the world as they provide nurseries for species of marine life that people depend on, store carbon dioxide, reduce coastal erosion rates and protect water quality. These functions help in mitigating climate change. Most seagrass losses have been linked to poor management of coastal zones, but the food chain variable has been mostly ignored. A lack of synchronized oversight has also led to habitat destruction, illegal fishing, overfishing and pollution.
Studies conducted on the impact of green sea turtles on seagrass meadows in India, Bermuda, Australia and Indonesia, which are places that are known for large populations of green sea turtles, suggest that seagrass communities are being disrupted by substantial grazing where populations of turtle are increasing and populations of sharks are low. Turtles are still threatened with extinction, so they must be conserved. However, there must be simultaneous efforts to rebuild and protect the populations of turtles and sharks throughout the world to make sure that they don’t create an imbalance in the ecosystem. Everyone can do their part in protecting these species by improving awareness about the conservation of turtles and sharks. Observing proper beach etiquette and proper waste disposal can also help.