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The heaviest non-crocodile reptile is the leatherback sea turtle, the lute turtle or the leathery turtle. It is the sole surviving member of the genus Dermochelys and the family Dermochelyidae.
Leatherback turtles have the most widespread global distribution of any turtle species, being found in the tropic and temperate seas of the Atlantic, Pacific, and Indian Oceans as far north as Alaska and as far south as New Zealand.
Description and Appearance
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They may grow to be up to 2 meters long and 600 kilograms in weight. Its absence of a bony shell distinguishes it from other current sea turtles. Instead, its carapace is covered by oily flesh and flexible, leather-like skin, after which it is called. The Tropical Sea Turtle Soft Stuffed Plush Toy from Gage Beasley gives you the same soft and plush skin.
Gage Beasley's Tropical Sea Turtle Soft Stuffed Plush Toy
Adults may span 2.7 meters from the tip of one front flipper to the end of the other. They have a secondary palate consisting of the vomer and palatine bones. The shell is there; however, it is made up of bones hidden beneath the skin's dark brown or black color.
It features seven distinct ridges on the backside and five on the bottom. When viewed above, leatherback hatchlings appear primarily black, with white margins on their flippers. Rows of white scales provide the white striping that runs down the length of hatchling leatherbacks' backs.
They have a network of blood arteries that act as a counter-current heat exchanger, a thick insulating coating of oils and fats in their skin. They can keep their body temperature substantially higher than the temperature of their environment.
Diet
These turtles eat in waters that are significantly colder than those tolerated by regular sea turtles.
Adult leatherback turtles rely nearly exclusively on jellyfish to survive. Leatherback turtles help limit jellyfish numbers since they are obligatory feeders. Leatherbacks consume tunicates and cephalopods, among other soft-bodied creatures.
Pacific leatherback turtles move 9,700 kilometers across the Pacific from their breeding locations in Indonesia to consume California jellyfish.
Reproduction
Mating occurs at sea. Males never leave the water after entering it, while females nest on land. After encountering a female, the male employs head motions (who may release a scent to advertise her reproductive state). The female's receptiveness is determined by nuzzling, biting, or flipper motions. Males can mate once a year, while females can only mate once every two to three years. Internal fertilization occurs, and many males often mate with a single female. This approach offers no specific advantages to the children.
Male leatherback turtles will often travel offshore before the breeding season begins. They will try to mate with as many females as possible there. Furthermore, studies have indicated that if the males were successful the previous season, they would return to the same nesting site.
Leatherback sea turtles mate in the ocean near the females' preferred nesting beach. The female then swims ashore at night to lay her eggs, which generally number between 50 and 170. However, a significant proportion of those eggs are yolkless and will not develop further. The female will lay her eggs and then cover the nest with sand to keep predators away and keep the temperature and humidity surrounding the eggs reasonable. After completing this process, the female will return to the ocean. Male leatherback sea turtles never swim to land and play no role in nesting.
Birds, tiny animals, and other opportunists may dig up turtle nests and devour turtle eggs. Shorebirds and crabs feast on hatchlings fleeing to the sea. They fall victim to predatory fish and cephalopods as they reach the water.
Habitat
Leatherback sea turtles are primarily found in the open ocean. Leatherback turtles follow their jellyfish prey throughout the day. Hence, they "prefer" deeper water during the day and shallower water at night (when the jellyfish rise up the water column).
This hunting tactic frequently places turtles in freezing water. Following each foraging dive, the leatherback would resurface to warmer surface waters (63.5 °F) to restore body heat before diving into near-freezing depths again. Except for beaked whales and sperm whales, leatherback turtles have been observed pursuing prey deeper than 1000 m—well beyond the physiological limitations of all other diving tetrapods.
Their preferred breeding beaches are those on the mainland facing the deep sea, and they appear to avoid those sheltered by coral reefs.
Conservation
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Plastic bags floating in the water are one of the causes of their endangered status. Plastic bags are mistaken for jellyfish by Pacific leatherback sea turtles; an estimated one-third of adults have consumed plastic. Plastic penetrates the waters around the west coast of metropolitan regions where leatherback turtles graze, with Californians using an estimated 19 billion plastic bags each year.
Several sea turtle species regularly consume plastic marine garbage. Even small amounts of debris can kill sea turtles by clogging their digestive processes. Nutrient dilution, which happens when plastics replace food in the intestine, impacts nutrient uptake and, as a result, sea turtle growth. Ingestion of marine debris and decreased nutrient growth increase the time required for sexual development, which may alter future reproductive activities. These turtles are most in danger of meeting and consuming plastic bags offshore of San Francisco Bay, the mouth of the Columbia River, and Puget Sound.
Leatherbacks have fewer human-related hazards than other marine turtles. Their flesh is excessively oily and fatty to be considered tasty, which reduces demand. Human activity, however, continues to imperil leatherback turtles in both direct and indirect ways. Subsistence fisheries directly catch a few for their flesh. Humans raid nests in regions like Southeast Asia. The most common cause of leatherback stranding is vessel-strike injuries, which account for nearly one-quarter (23.5 percent) of all strandings.
Light pollution is a severe hazard to sea turtle hatchlings drawn to light. Human-generated light from lamps and buildings disorients hatchlings, causing them to move toward the light and away from the beach. Hatchlings are attracted to light because the horizon over the ocean is the lightest place on a natural beach. In contrast, the dunes or woodland are the darkest.
Other Interesting Facts
- Leatherback turtles get their name from their rough skin, which looks like rubbery leather.
- Leatherback turtles have razor-sharp teeth that let them cut through gelatinous food like jellyfish and salps.
- Leatherback turtles are the only turtle species that lack a hard shell and scales.
- Leatherback turtles can dive for up to 85 minutes.
Final Thoughts
Adult leatherback turtles have few natural predators; they are most vulnerable to predation in their early life stages.
Designating critical habitats for leatherback turtles will bolster safeguards for other aquatic species in the Pacific Coast coastal environment. The preservation of foraging areas and migratory corridors is essential to recovering this endangered species.
Cheers!
~GB
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