Green sea turtles, are a species of marine turtle that live in tropical and subtropical oceans around the world. They have long been admired for their unique behaviors, which often display intelligence and social interaction. Green sea turtles are majestic creatures that have captivated people for centuries. They inhabit the oceans of the world and are found in tropical and subtropical regions. As a species, they have adapted to their environment by developing specific behaviors that help them survive. In this article, we will explore the various behavior characteristics of green sea turtles and how they interact with their environment. From their feeding habits to their social behavior, we will gain an understanding of what makes these incredible animals unique.
Anatomy and Structure of Green Sea Turtles:
The green sea turtle (Chelonia ), also known as the green turtle, black (sea) turtle or Pacific green turtle, is a species of large sea turtle of the family . It is the only species in the genus Chelonia. Its range extends throughout tropical and subtropical seas around the world, with two distinct populations in the Atlantic andPacific oceans , but it is also found in the Indian ocean. The common name refers to the usually green fat found beneath its carapace, not to the color of its carapace, which is olive to black.
Appearance of green sea turtles:
Green sea turtles are amongst the largest turtles. Their heads appear small in comparison with the size of their body, which is covered in brown scales with a light-colored edge. Males are bigger than females and have a longer tail, sticking out well past the shell. The shell of the turtle has smooth, non-overlapping plates colored different shades of brown, with patterns that change as the turtle grows older. The underside of the shell is lighter colored. Green sea turtles are not able to pull their heads into their shells.
Distribution of green sea turtles:
Green sea turtles live in the Atlantic Ocean, ranging from the eastern part of the United States along the coast of South America and over to South Africa. They are also found in the Caribbean Sea and parts of the Mediterranean, and throughout the warmer waters of the Pacific and Indian Oceans. Green sea turtles move across three habitat types, depending on their life stage. They lay eggs on beaches. Mature turtles spend most of their time in shallow, coastal waters with lush seagrass beds. Adults frequent inshore bays, lagoons, and shoals with lush seagrass meadows. Entire generations often migrate between one pair of feeding and nesting areas. In these protected shores and bays, the green sea turtle habitats include coral reefs, salt marshes, and nearshore seagrass beds. The coral reefs provide red, brown, and green algae for their diet and give protection from predators and rough storms within the ocean. The salt marshes and seagrass beds contain seaweed and grass vegetation, allowing ample habitat for the sea turtles. Turtles spend most of their first five years in convergence zones within the bare open ocean that surrounds them. These young turtles are rarely seen as they swim in deep, pelagic waters.
Habits and Lifestyle of green sea turtles:
Green sea turtles spend almost all their lives underwater and come out of the water only when nesting. They are not considered social but may congregate offshore or during the breeding season. Some individuals may migrate together. Although they move quickly in the ocean, on land Green sea turtles are slow and also defenseless. Males hardly ever leave the water. Females leave the sea only to lay eggs and nest only at night. Green turtles swim underwater for approximately 4 to 5 minutes during routine activity and come up to breathe at the surface for 1 to 3 seconds. They can sleep underwater for a few hours at a time but stay beneath the surface for a much shorter period when diving for food or escaping from predators. Although green sea turtles can’t pull their heads inside their shells, the adults have protection from predators due to their shells, their large size, and the thick scaly skin covering their heads and necks.
Diet and Nutrition of green sea turtles:
The diet of Green sea turtles changes with age. Juveniles are carnivorous, but as they mature they become omnivorous. Young sea turtles eat fish eggs, mollusks, jellyfish, small invertebrates, worms, sponges, algae, and crustaceans. Most adult sea turtles are strictly herbivorous.
Green sea turtles are among the most iconic and beloved creatures in the ocean. These peaceful, beautiful reptiles have an important role to play in their environment, but what is their diet and nutrition?
Green sea turtles are omnivorous, meaning they consume both plant and animal matter. They feed primarily on algae and seagrasses, such as turtle grasses or manatee grasses. In addition to these plants, green sea turtles also eat jellyfish, small crustaceans like shrimp and crabs, mollusks such as clams and oysters, as well as fish eggs or larvae. Due to their large size when fully grown (up to three feet long), some adult green sea turtles may even eat larger prey such as stingrays or smaller sharks.
Mating Habits of Green Sea Turtles:
Green sea turtles are polygynandrous, and some populations have a polyandrous mating system, with one female mating with two or more male turtles. As with many species, males compete for a female. Breeding takes place in March-October, with variation between populations. Females mate usually every 2 to 4 years. The males visit the breeding grounds every year, looking for a mate. After copulation, when ready to lay her eggs, the female crawls ashore after dark. She digs a large pit beyond the high tide line and lays 70-200 eggs in it before returning to the ocean. The young turtles hatch after 6-8 weeks, and, with the help of their flippers, come up to the surface. They hatch at night and instinctively head directly into the water. Juveniles spend 3 to 5 years in the open ocean before they settle as still-immature juveniles into their permanent shallow-water lifestyle. It is speculated that they take 20 to 50 years to reach reproductive maturity.
Population Of Green Sea Turtles:
The main threats to these turtles include the degradation and loss of habitat, consumption of their eggs and meat, capture as bycatch, pollution, and climate change. Beach armoring, building works, and sand extraction degrades the nesting habitat, while light pollution in the nesting areas fatally attracts hatchlings so that they do not head for the sea. Increased effluent, contamination from coastal development, and over-harvesting of algae all threaten the habitat of the green sea turtle.
According to the Sea Turtle Conservancy resource the total population size of nesting Green sea turtles is around 85,000-90,000 individuals. Overall, currently, this species is classified as Endangered (EN) on the IUCN Red List and its numbers today are decreasing.
Green sea turtles eat seagrasses and algae, thus serving (much like mowing a lawn) to maintain the seagrass beds in a healthy state, making them more productive. Seagrass eaten by the turtles is quickly digested, becoming available as recycled nutrients for the many species of animals and plants that live in the ecosystem of seagrass. Seagrass beds also act as nurseries for a number of species of fish and invertebrates, many being of considerable value for commercial fisheries and thus important for human food security.
Characteristics and Appearance of Green Sea Turtles:
Weight & Length
Green sea turtles are some of the largest turtles in the entire world. Newborn green sea turtles start at a size of smaller than eight inches long. An adult green sea turtle’s shell can measure anywhere from three to five feet in length. They can weigh as little as 240 pounds or reach up to an astonishing 70 pounds, depending on their sex and health.
The largest green sea turtle ever recorded was 5 feet long and 871 pounds.
Physical Characteristics and Color:
Green sea turtles received their name based on their cartilage and fat’s green color and not the color of the shell itself. In fact, a green sea turtle’s shells tend to range from shades of brown to olive. The Pacific green sea turtle, found in Alaska’s coastal waters to Chile, has a dark grey or black shell, which has earned them the unofficial name of the “black turtle.”
Their bodies are flat and oval-shaped. Most sea turtles have two pairs of scales in front of their eyes, known as prefrontal scales. Green sea turtles only have one pair of prefrontal scales, making them easily distinguishable from other sea turtle species. Their heads are small and blunt with a serrated jaw, and their shell is composed of large, non-overlapping scales with four scales on each side. Each flipper has at least one visible claw.
Lifespan and Reproduction of Green Sea Turtle:
Oddly enough, the exact lifespan of green sea turtles is unknown but is estimated to be 70 to 80 years old at the minimum. Green sea turtles become sexually mature around 25 to 30 years old but may not begin nesting until they’ve reached almost 40 years old.
Like their lifespan, the green sea turtle’s active reproductive period is also unknown, but some turtles have been observed nesting for approximately 38 years. Male green turtles can mate every year, but females travel from their foraging areas to their nesting beaches every two to five years. Green turtles return to the same beaches that their mothers used. The act of mating occurs at the green sea turtle’s foraging grounds, along migration paths, and offshore of nesting beaches. The nesting period depends on the region, but green sea turtle nesting in the United States occurs in late spring and early summer when temperatures are warm. While at their nesting area, a female green sea turtle will lay approximately 100 eggs per nest and nest every couple of weeks over several months before returning to their foraging grounds.
Where Does the Green Sea Turtle Live?
Geographically, green sea turtles are found anywhere globally with warm subtropical and tropical ocean waters, with nesting occurring in over 80 countries. The green sea turtle can be found in the Atlantic, Indian, and Pacific Oceans. Once a hatchling green sea turtle leaves its nest for the first time, it rarely returns to land throughout its life. They stay in shallow waters offshore, where it feeds on vegetation near islands and beaches. Green sea turtles tend to have complex, confusing, and unique migration patterns because each turtle prefers to return to their natal beach for each nesting season (where they were originally born). They’ll travel far distances and even traverse oceans. The Hawaiian Islands, east coast of Florida, Virgin Islands, and Puerto Rico are all hotspots in the United States where green sea turtles are frequently seen. Rarely, green sea turtles can be observed nesting along the Atlantic coast in Georgia and North and South Carolina. Outside of the United States, green sea turtles live near the Mesoamerican Reef, Coastal East Africa, Galápagos, and the Coral Triangle.
Overall, green sea turtles can be spotted anywhere with warm coastal waters and sandy beaches.
What Does the Green Sea Turtle Eat?
Another rarity that sets the green sea turtle apart from its counterparts is its diet. The green sea turtle is one of the only sea turtles that are completely herbivorous once they reach adulthood and enjoy feeding on sea vegetation such as algae and seagrasses.
Their serrated jaws help them tear into patches of dense vegetation. Juvenile green sea turtles have slightly varied diets from adults and start omnivorous, eating worms, sea crustaceans and invertebrates (crabs, jellyfish, sponges), and aquatic insects.
Threats and Predators of Green Sea Turtle:
Green sea turtles face many threats to their population’s well-being, including humans and natural predators.
Human Threats: There are several threats by humans that harm the green sea turtle population. The largest loss of life to the green sea turtle is attributed to “bycatch,” which occurs when sea turtles are caught by fishermen netting for shrimp and other fish. Sea turtles need to frequently return to the surface for air and end up drowning while trapped in these nets. Per year, the fatalities from bycatching climb into the hundreds of thousands. Overharvesting and illegal trade are the second most harmful practices to the green sea turtle. Poachers hunt the green turtle for its eggs and internal organs. In West Africa, sea turtles are killed so individuals can use them in ceremonies and medicinal remedies. Lastly, habitat loss deeply impacts the green sea turtle population. Coastal development, unmonitored beach traffic, and other invasive human activities contribute to a massive environmental loss.
Climate Change and Global Warming of Green Sea Turtles:
Climate change and global warming affect multiple aspects of the green sea turtle’s environment. Additionally, the rising sea levels and vicious storms contribute to the loss of beach habitats, affecting green turtle breeding.
The warmer temperatures in these beach habitats also contribute to more female hatchlings than males, leading the species closer to extinction.
While green turtles are particularly vulnerable to being eaten by nocturnal predators, newborn green sea turtles hatch during the nighttime due to predators’ overall decreased presence. Mature green sea turtles do not have many predators in the open ocean but can be placed in dangerous situations near sharks and other large predators. The most vulnerable life stage of a green sea turtle is infancy.
Some predators will dig up green turtle nests before the eggs have a chance to hatch.
In conclusion ,the green sea turtle is an amazing creature with unique behavior characteristics. Its ability to migrate long distances and return to the same beach for nesting is remarkable. Its diet of mainly algae and its tendency to remain close to the shoreline makes it a fascinating species to study. The green sea turtle is threatened in many ways, such as habitat destruction and poaching, however, conservation efforts are being made that are helping the population recover.