Tahukah Anda
MARINE TURTLE LIFE-CYCLE
Marine turtles, also known as sea turtles, have a complex and fascinating life-cycle that spans decades and crosses oceans. There are seven species of marine turtles, and while specific details can vary slightly among species, the general life-cycle stages are similar.
- Egg Laying (Nesting): The life-cycle of a marine turtle begins when a female turtle returns to her natal beach—often the same location where she was born—to lay her eggs. After mating at sea, the female comes ashore to dig a nest in the sand with her flippers. She typically lays between 50 to 200 eggs, depending on the species. These eggs are left in the nest, covered with sand to incubate and protect them from predators.
- Incubation: The eggs incubate for about 50-70 days. The temperature of the sand determines the sex of the hatchlings; warmer temperatures generally produce more females, while cooler temperatures produce more males.
- Hatching: The hatchlings emerge from their eggs and make a perilous journey from the nest to the ocean. They do this primarily at night to avoid predators and the harsh sun. Many hatchlings are picked off by birds, crabs, and other predators during this journey.
- Pelagic Phase (Oceanic Stage): Once in the ocean, young turtles enter a pelagic phase where they drift with oceanic currents. This phase, which can last from a few years up to a decade, involves high mortality rates due to predation and harsh oceanic conditions. The turtles grow rapidly during this stage, feeding on a variety of available oceanic organisms.
- Juvenile Phase: After the pelagic phase, the juvenile turtles settle in more defined feeding territories, typically in coastal areas rich with seagrass and algae. They remain in these juvenile habitats for several years, continuing to grow until they reach sexual maturity.
- Adult Phase and Reproduction: Once mature, marine turtles undertake migrations to breeding areas, where they find mates. After mating, female turtles repeat the cycle by returning to their natal beaches to lay eggs. This migration and nesting cycle can vary widely among species and individuals; some turtles may nest every 2 to 4 years.
- Longevity and Threats: Marine turtles have long lifespans, often exceeding 50 years in the wild. They face numerous threats throughout their lives, including habitat loss, pollution, accidental capture in fishing gear, climate change, and illegal hunting. Conservation efforts are crucial to their survival, focusing on protecting nesting beaches, regulating fisheries, and mitigating climate change impacts.
Understanding the life-cycle of marine turtles is key to their conservation, as it helps identify the critical stages where intervention can have the most significant positive impact.
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