Jul 22, 2011

JTP Turtle Talk (2)

Part 1

So what do we do at JTP ? We focus on sustaining the turtle population, habitat defence and raising awareness. This brings us to understand and work with the nature, people, economy and politics of this island. We are not hippies or treehuggers, we are working toward a specific goal here. We work toward not having to run a conservation effort like this because people will be conscious and protective of nature around them and wild life in the area including sea turtles.

Sea turtles have many natural predators at different stages of their lives. For the eggs in a nest on the beach, any animal that can dig is a threat. Dogs, lizards, crabs, snakes etc. For the hatchlings coming out of the eggs the threat is from birds, crabs and carnivore animals on the beach. Once they reach the ocean, any fish bigger than them is a predator. This includes sharks, barracuda etc. Sharks will prey upon sea turtles untill they reach a certain size when they become quite a mouthfull for a shark, that's when sharks usually leave them alone. After reaching maturity, there is hardly any animal posing threat to sea turtles, except humans.

Green sea turtles (Chelonia mydas) drowned in a gillnet. Turtles become entangled and are unable to surface to breathe.
Green sea turtles (Chelonia mydas) drowned in a gillnet. Turtles become entangled and are unable to surface to breathe.

Humans kill sea turtles by accident and also by purpose. Accidental killing can occur in many forms. Fishing by-catch is responsible for most accidental sea turtle deaths. Turtles often fall victim of long line fishing, trawling and other fishing methods. Since they need to breathe air, they will drown if subjected to stay under water for a long time caught in a fishing net, hook or other fishing device. There are devices like TED(Turtle Excluder Device) that enables commercial fishing boats to catch fish from the sea without harming bigger animals like turtles and dolphins. It's mandetory in many parts of the world to use TED in commercial fishing boats, but the law is not strongly enforced everywhere.

Loggerhead turtle escaping a turtle excluder device (TED)
Loggerhead turtle escaping a turtle excluder device (TED)

Besides this, turtles can also die from collision with boats. Since their backbone is connected with the shell on their back, any fracture or injury to the shell actually means a major damage to the spinal chord which often results in death of the turtle.

Pollution is another turtle killer. We often throw out plastic bags in to the ocean or rivers without thinking twice. The leatherback turtles feed on jelly fish and plastic bags floating in sea look like jelly fish. When a turtle eats a plastic bag, it's digestive track is blocked and can also lead to the turtle's death.

Light pollution also affects the turtles badly. When sea turtle hatchlings come out of a nest, they look towards the horizon to determine the direction to the sea. Naturally, the ocean side of the horizon always is a little brighter than the mainland side and this faint natural light shows them the way. Now imagine some man made light source like street lamps along a high way running along the coast, lights from hotels, chalets, resturaunt and bars on the beach or simply someone's brightly lit house. Light from these sources are much brighther than the faint natural light on the horizon and hatchlings are distracted toward them. Instead of heading to the ocean, baby turtles end up in bars. Or some other place in the dry land where they can be preyed upon by other animals or would die simply from exhaustion or dessication.

Something seemingly innocent as beach furniture can also kill a turtle. Imagine a beach chair left unattended on the beach gets washed away into the ocean and traps a turtle under it and eventually the animal drowns. When a mother turtle comes up to nest, she is very picky about the nesting site. Noise, bright light, obstacles like beach furniture or the mere presence of humans will make her turn back to the ocean. But how long can a turtle carry 150 eggs ? She has to get rid of them at some point because her body will be producing more eggs soon. She will try as long as she can hold, but if she cannot find a suitable place to nest she will dump all the eggs in the water.

Humans kill turtles on purpose too, more than by accident. We hunt them for meat, we collect turtle eggs for consumption. In certain cultures, sea turtle soup is considered a delicacy. In fact, the green turtle was named so because the soup they make from this kind of turtle is green. This is because the fat inside the turtle's body is green in color. Another kind of turtle, the hawksbill is often hunted down by turtle poachers. Hawksbills feed on a venomous sponge growing on corals and this makes their meat poisonous for humans. But it's not the meat that people are after, they are after the beautiful black, brown and amber shell that these turtles have. Sea turtle shell souveniers like sunglass frames, buttons, combs etc. are traditionally made from hawksbill shells. People kill turtle for cultural or religious purpose too. In some cultures, killing a turtle is a rite of passage for male members of the community.

(to be continued ...)

Image credit :
1. Projeto Tamar Brazil-Image Bank

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