2008) and hence, assessment of factors driving offspring survival has been a central component of ecological studies for many decades (Gibson et al. The survival rate of offspring is a key demographic factor that drives the success of populations (Albon et al. We discuss how either nest protection and/or invasive predator eradication may be used to increase egg survival and when these approaches might be used. ![]() Depending on location, a predator could be identified as both native and invasive (e.g., dogs). We reviewed evidence from 34 sites around the world identifying 36 predators that were either native (e.g., crabs, and goannas, n = 30) or invasive (e.g., rats, and pigs, n = 8). Overall, hatching success (the percentage of eggs laid leading to a hatchling emerging from the egg) was 64.9%, while 3.1% of eggs were predated within nests, 18.1% died during incubation without predation and 13.9% were removed. In other cases, egg predation was recorded where the egg had been opened and contents were eaten in the nest. For example, the mean clutch size at oviposition (mean 127.8 eggs, n = 23, range = 74–176) was significantly larger than at the end of incubation (mean 110.9 hatched and unhatched eggs, n = 16, range = 9–147). Often whole eggs were removed from clutches. Native coconut crabs ( Birgus latro) and ghost crabs ( Ocypode spp.), as well as introduced black rats ( Rattus rattus), were predators of eggs, with these species entering nests via tunnels dug obliquely in the sand. We assessed the levels of egg predation within green turtle ( Chelonia mydas) clutches on the island of Diego Garcia (7.42°S, 72.45☎), Chagos Archipelago (Indian Ocean). The fastest turtles are the leatherbacks which have been known to swim at speeds of over 20 miles per hour.Egg predation by invasive and native species may have severe impacts on endangered species and negatively affect species recovery.These tears are from special glands that allow them to get rid of extra salt they get by living in salt water oceans. Sea turtles sometimes look like they are crying.They can live off of the water they get from their food. Sea turtles don't need a supply of fresh water.Leatherback sea turtles have been known to dive over 1000 feet deep in the ocean.Many sea turtles can hold their breath for over 30 minutes.They are very vulnerable to predators during this time. Once the eggs hatch, the hatchlings head for the water. The eggs are left defenseless and become prime food for many predators. Then the mothers leave and go back into the ocean. Mother sea turtles lay lots of eggs on the beach in a hole they dig. However, baby Sea turtles are highly vulnerable when they are born. Grown sea turtles have very few predators. Sometimes the back flippers are used for digging holes where the turtle lays eggs.ĭepending on the species and age of the turtle, sea turtles eat all kinds of food including sea grass, seaweed, crabs, jellyfish, and shrimp. The front flippers are used to propel the turtle through the water while the back flippers are used for steering. These flippers can also help propel them on land, but not very well, making sea turtles easy prey to predators on land. Sea turtles have flippers that enable them to swim well. Sea turtles don't retract into their shells like some turtles. Some are oval and some are more heart shaped. Different species have different shaped shells. The top side of the shell that we see is called the carapace. Like other turtles, sea turtles have a hard shell that acts as armor and protects them from predators. ![]() They grow to around 2 feet long and 100 pounds. The largest is the leatherback which can grow up to 6 feet long and weigh well over 1,000 pounds! The smallest are the olive ridley and the Kemp's ridley turtles.
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