A few months ago, out at the edge of the world near Derawan Island off the eastern coast of Indonesia, I swam with the sea turtles. They seemed unimpressed and nonplussed with the human darting around them. They continued on their way, slow and steady, graceful and ancient. I couldn’t stop watching them.
Sea Turtles have existed on our planet for 100 million years and travel throughout the world’s oceans. They carry with them an other-worldliness, a glimpse to a time long before humans even existed. Today, these ancient mariners struggle to survive. Nearly all species of sea turtles are classified as endangered.
Humans slaughter them for their eggs, meat, skin, and shells and destroy their habitats. Climate change alters sand temperatures, affecting the sex of hatchlings. Turtles often find themselves entangled in fishing gear, or plastic waste and other garbage in the oceans. Sea turtles need us to help protect them and the waters they swim in. They need people to educate and work with local communities to reduce turtle harvesting and egg collection. They need us to establish marine protected areas and to monitor and guard their nesting beaches.
What most people don’t realize is that we need sea turtles just as much, even more, than they need us. They have, after all, been around about 99 million 800 thousand years longer than we have.
Hawksbill Turtles, named for their narrow pointed beaks, help maintain coral reefs by removing prey such as sponges. They also have great tourism value (I can attest to that!) The turtles use their beaks to extract the sponges from crevices in the reef and are a fundamental link in the marine ecosystem. Without Hawksbills, sponges are likely to dominate reef communities, limiting the growth of corals.
Leatherback turtles, the largest of the species, migrate great distances, crossing both the Atlantic and the Pacific Oceans. Their shells, rather than being hard like other turtles, are more like leather. Known to consume up to 440 pounds of jellyfish a day, they travel to the coast of California all the way from their nesting beaches in the Coral Triangle to feed on jellyfish every summer and fall. Sadly, the turtles often mistakenly swallow floating plastic bags that a lot look like dinner and end up dying.
Also, as a result of overfishing many types of finfish, jellyfish are slowly replacing other fish populations. The increase of jellyfish, which feed on fish eggs and larvae, leads to an even more significant decrease in other fish populations.
The Green Turtle, found mainly in tropical and sub tropical waters, is the only herbivore sea turtle. They graze on sea grasses and algae, helping to keep the grass beds more productive and healthy. The turtles quickly digest the sea grass and the recycled grass provides nutrients to other creatures that live on the ocean floor.
The most common sea turtle in the Mediterranean is the Loggerhead. They feed on hard-shelled prey and in turn recycle nutrients and keep ocean floor sediments in balance. Their shells also serve as habitats for 100s of species of small plants and animals such as barnacles, algae and other organisms known as epibionts. In turn, sheepshead bream, wrasses, angelfish, and barber pole shrimp set up ‘cleaning stations’, or feeding stations for sea turtles to visit. In this way, the turtles provide meals to various fish and shrimp.
Out in the open ocean, far from shore, sea turtles provide an oasis to fish and seabirds. Olive Ridleys, named for the olive color of their shells, are the smallest of the sea turtles. In the Eastern Tropical Pacific, the turtles surface to bask in the sun, exposing the center of their shells, which serve as a perfect platform for seabirds to perch. Small baitfish also seek protection underneath the turtles.
Sea Turtles play a vital role in maintaining the health of our oceans. By grazing on sea grass, controlling sponge populations, feasting on jellyfish, and transporting nutrients and supporting other marine life, they are an essential and vastly important link in the marine eco system. Our oceans are unhealthy and significantly threatened by over fishing, pollution, and climate change. Protecting sea turtles and rebuilding their populations are important steps in ensuring healthy and resilient oceans in our future.
- Tags: Animal Conservation