Green sea turtles are one of the most iconic and fascinating creatures of the ocean, known for their gentle nature and vital role in marine ecosystems. Named not for the color of their shells but for the greenish hue of their body fat (a result of their herbivorous diet), these turtles are a symbol of resilience and the beauty of the natural world. Found in tropical and subtropical waters around the globe, green sea turtles play a crucial role in maintaining healthy seagrass beds and coral reefs. However, despite their importance, green sea turtles face numerous threats, from habitat destruction to climate change. In this blog, we’ll dive into the world of green sea turtles, exploring their unique characteristics, their critical role in the ocean, and the challenges they face in today’s changing environment.

Green sea turtles are the largest of all hard-shelled sea turtles, reaching lengths of over 3 to 4 feet and typically weighing between 300 to 350 pounds, though some can weigh up to 500 pounds. Despite their large size, they have a relatively small head. Their smooth carapace varies in color, ranging from shades of black, gray, green, brown, or olive, with a much lighter yellowish-white underside known as the plastron. The shell consists of two parts: the carapace (top) and the plastron (bottom), and is composed of bony plates covered with horny shields. Green sea turtles have five scutes running down the middle of their shell and four scutes on each side. Distinctive features include their serrated beak, which is perfectly adapted for grazing on seagrass and scraping algae, and two large scales located between their eyes. Additionally, their forelimbs are significantly larger than their back flippers, specially modified for swimming, and each flipper has one claw.

As hatchlings, green sea turtles look quite different from their adult counterparts. They are tiny, measuring only about 2 inches long, and weigh just a few ounces. Their shells are almost completely black, providing camouflage in the open ocean, with a white underside that helps protect them from predators below. Unlike adults, which are primarily herbivorous, hatchlings are omnivorous and feed on small marine organisms as they drift in ocean currents. Over time, as they grow and develop, their shells lighten in color, and they transition to the larger, more recognizable appearance of an adult green sea turtle.

Green sea turtles are remarkable creatures with fascinating behaviors that set them apart from other marine animals. As reptiles, they must come to the surface to breathe and return to land to lay their eggs. What’s truly incredible is their ability to migrate hundreds—even thousands—of kilometers between their foraging grounds and nesting beaches. Some green turtles have been known to travel up to 3,000 kilometers, navigating vast ocean distances with astounding accuracy.

These gentle giants lead solitary lives, with female turtles nesting primarily at night. However, green sea turtles are unique among sea turtle species for another reason—they are the only ones known to come ashore regularly to bask in the sun. This behavior, seen in places like Hawaii, the Galapagos Islands, and parts of Australia, is both a way to conserve energy and a rare chance for people to observe them up close.

The journey of a green sea turtle begins as a hatchling, making its first migration from the beach where it was born to the open ocean. For several years, these young turtles live in pelagic habitats, feeding on floating plants and animals in oceanic drift communities. Once they mature, they move to shallow coastal waters, where they adopt a primarily herbivorous diet of seagrasses and algae, though some populations may eat sponges and invertebrates.

Every 2 to 5 years, adult turtles undertake their most important migration—returning to their birthplace to lay eggs and continue the cycle. These migrations are not only a testament to their endurance but also highlight the importance of preserving their habitats at every stage of life. From their dramatic migrations to their unique basking habits, green sea turtles remind us of the incredible complexity and beauty of marine life, and the importance of protecting these ancient travelers for future generations to admire.

Green sea turtles are true globetrotters, found in tropical and subtropical waters all over the world. They inhabit the Atlantic, Pacific, and Indian Oceans, as well as the Mediterranean Sea, making their range one of the widest among sea turtle species. In the U.S., they can be found along the coasts from Texas to Maine, as well as in Puerto Rico and the U.S. Virgin Islands. Florida is a particularly important hotspot, with major feeding areas like the Indian River Lagoon, the Florida Keys, and the Dry Tortugas. On the Pacific side, green turtles range from southern California to northwestern Mexico, occasionally traveling as far north as Alaska. Other key habitats include Hawaii, American Samoa, Guam, and the Northern Mariana Islands.

When it comes to nesting, green sea turtles are just as widespread. Major nesting beaches can be found in Tortuguero, Costa Rica; Raine Island, Australia; Oman; and Florida, where thousands of females nest during peak seasons. They also nest in the Hawaiian Islands, Guam, American Samoa, Suriname, and even the southeastern U.S. states like Georgia and the Carolinas.

Green turtles use a variety of habitats throughout their lives. Hatchlings and juveniles spend their early years in offshore convergence zones, while adults move to shallow coastal waters with seagrass beds and algae-rich bays and lagoons, which serve as their primary foraging grounds. For nesting, females seek out undisturbed sandy beaches with gentle slopes. Their ability to use such a wide range of habitats shows their adaptability, but it also highlights the need for global cooperation to protect the places they rely on throughout their lives. From feeding in calm lagoons to nesting on remote beaches, green turtles are a vital part of many marine ecosystems around the world.

Green sea turtles are among the longest-living creatures in the ocean, with lifespans that can exceed 70 years. However, reaching maturity is a slow process, taking anywhere from 20 to 50 years. Once they reach adulthood, female green turtles begin one of nature’s most remarkable cycles: returning to the beaches where they were born to nest. This incredible migration occurs every 2 to 5 years, with females often traveling hundreds or even thousands of kilometers to lay their eggs.

During nesting season, which begins in late spring in the United States, females lay multiple clutches of eggs—typically about 5 clutches—spaced two weeks apart. Each clutch can contain an average of 110 to 135 eggs. After being laid, the eggs incubate for about two months beneath the warm sand. When it’s time to hatch, the tiny hatchlings, only about 2 inches long, instinctively crawl toward the brightest horizon, which on natural beaches is the open ocean. This journey can be perilous, but it marks the start of their incredible lives.

Once in the ocean, hatchlings are believed to spend their early years in offshore habitats, growing and developing in pelagic areas far from shore. As they grow older and larger, juveniles move to coastal foraging grounds, where they spend the rest of their lives. The reproductive cycle of green sea turtles is a testament to their resilience and connection to the natural world, and it highlights the importance of protecting both their nesting beaches and ocean habitats to ensure their survival.

Green sea turtles face numerous threats that challenge their survival and highlight the urgent need for conservation efforts. One of the biggest threats is bycatch, where turtles are unintentionally caught in fishing gear like trawls, gillnets, and longlines. These accidental captures can cause severe injuries or even drown turtles. Similarly, marine debris and ocean pollution, including discarded fishing gear, plastic bags, and balloons, can entangle or be mistaken for food, leading to injury or death. Oil spills, like the Deepwater Horizon disaster, have also had devastating effects on green turtles, harming their habitats and their ability to reproduce.

Loss of nesting habitat is another significant concern. Coastal development, artificial lighting, and rising sea levels from climate change have eroded beaches, leaving females with fewer safe places to lay eggs. Nesting females are also at risk of vessel strikes, especially in areas with heavy boat traffic near marinas and inlets. Climate change further compounds these challenges by raising sand temperatures, which can skew the ratio of male to female hatchlings or even cause eggs to fail entirely.

Additionally, fibropapillomatosis, a disease that causes tumors on green turtles, is becoming increasingly common. These tumors can interfere with their ability to swim, eat, and even survive. Historically, the direct harvest of turtles and their eggs led to a dramatic decline in green turtle populations. Although harvesting is now illegal in many countries, it still occurs in some areas, disrupting recovery efforts.

Despite these challenges, there is hope. Conservation programs, such as protecting nesting beaches, regulating fishing practices, and raising public awareness, have helped stabilize some populations. However, with global populations still much lower than historic levels and many populations listed as endangered or threatened, continued efforts are essential to ensure these ancient ocean travelers have a future. Protecting green sea turtles is not just about saving a species—it’s about preserving the health of our oceans for generations to come.

Green sea turtles are not just beautiful creatures of the sea—they are vital to the health and balance of marine ecosystems. From keeping seagrass beds in check to supporting vibrant coral reefs, their presence benefits countless other species, including humans. However, their survival is far from guaranteed as they face growing threats from climate change, pollution, and human activity. By raising awareness, supporting conservation efforts, and taking small steps to protect our oceans, we can help ensure that green sea turtles continue to thrive for generations to come. Their future is in our hands, and every effort we make brings us closer to preserving the natural beauty and balance of our planet. Together, we can make a difference. Make sure to come back next month for the next edition in our sea turtle series!