![]() They are less common in North Carolina than loggerheads. Green sea turtles are named for the green color of their fat, not their shell as most people think. Green sea turtles are herbivores as adults. They can reach up to five feet and can weigh up to 650 pounds. Green sea turtles are larger than loggerheads. Loggerhead sea turtles have five scutes down each side of their shell, whereas greens only have four. It is possible to count the number of scutes on the shell to identify one from the other. Loggerhead and green sea turtles look similar as adults. Historically, they nested as far north as Virginia. These turtles nest as far north as Ocracoke Inlet in North Carolina and as far south as Florida. Tagged adults have been found thousands of miles from where they were originally marked. Loggerheads tend to travel great distances. Sailors seeing the head poke above the surface to breathe would often mistake them for logs, so they named them loggerheads. They may weigh as much as 500 pounds, but 350 pounds is more common. Maintaining natural predator-to-prey interactions in the oceans by conserving tiger sharks and turtles and all such symbiotic relationships is important to ensuring the overall health of ocean ecosystems.A loggerhead sea turtle’s shell can reach 3-4 feet. And in the Atlantic, the disappearance of seagrasses off Bermuda may be due to reductions in tiger sharks and the consequent increase in turtles, which are major seagrass grazers. Overfishing of sharks in the Pacific, for instance, along with diminished human take of turtles over decades, is likely one of the factors behind the rise in Hawaiian green turtle numbers in recent decades. Tiger sharks certainly play an important role in regulating turtle populations. In response, turtles have likely adopted behaviors, like choosing lower risk habitats (for instance, green turtles basking on shore), to reduce the hazard posed by tiger sharks. Indeed, sea turtles worldwide are at risk from tiger shark predations in shallow seagrass ecosystems, coral reefs, and the open sea. Tigers grow to over 4.5 meters (about 15 feet) and have broad heads that can accommodate large prey and curved, serrated teeth that cut in both directions when the sharks shake their heads, an adaptation that enables them to cut through a turtle’s thick shell. In fact, tiger sharks may have evolved specifically to feed on sea turtles. But tiger sharks frequently prey on large juvenile and adult sea turtles. Although white sharks and bull sharks have been recorded eating sea turtles-including accounts of white sharks taking adult leatherbacks-those two species rarely dine on sea turtles. At sea, large sharks are the primary threat to adult sea turtles, although killer whales may occasionally take sea turtles. But in Central and South America, American crocodiles and jaguars are a threat to nesting females, and in the Indo-Pacific, saltwater crocodiles prey on adult turtles both on nesting beaches and in inshore waters. Once they have survived hatchlinghood and have large bodies and hard shells, adult sea turtles might be more immune to predators. In those habitats, too, the turtles are consumed by large bony fish and sharks, though we still cannot quantify the magnitude of this predation, nor do we know what other risks turtles may face during the posthatchling portion of their lives. And when they reach deeper waters or the safety of mats of floating algae, the risks decline but don’t disappear. During their frenzied swim to reach deeper water, hatchlings are eaten by large bony fish, sharks, and sea birds. Once they reach the water’s edge, things don’t get any easier. Hatchling turtles are at even greater risk from mammals, birds, and crabs as they cross the beach to the sea.
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