Green sea turtle

Green sea turtle

Introduction
Sea turtles appeared about 200 million years ago and survived drastic changes that occurred on Earth. With the arrival of modern man, populations of this animal group have been used to such extent that today they are in danger of disappearing in most parts of the world.

In Puerto Rico, there are very few nesting areas because man has intervened and destroyed their nests in his desire to obtain eggs. Of the few turtles that climb up to our beaches to nest, most are hunted in our waters to meet the needs of a growing black market. The few nesting areas that we still have are disappearing as a result of construction of neighborhoods, industries, and tourist resorts in Puerto Rico’s coastal areas.

What are the most common turtle species in Puerto Rico?

The most common species found in Puerto Rico are the Hawksbill sea turtle (Eretmochelys imbricata), Green sea turtle (Chelonia mydas), and Leatherback sea turtle (Dermochelys coriacea). The leatherback sea turtle does not remain in our waters all year; it only visits in the summer.

Hawksbill Sea Turtle (Eretmochelys imbricada) – Hawksbill is the most beautiful of sea turtles. Its hard carapace, called a shell, is formed by brown or dark brown and amber yellow plates. These plates are superimposed like roof tiles. The shell underside is called a plastron and is yellow. The skin on the head and fins has brown spots surrounded by yellow. This sea turtle measures slightly less than one meter in length and weighs just over 45 kilograms. Sea and terrestrial turtles are reptiles, have lungs, and breathe air. Although sea turtles may hold their breath for several minutes, they must rise to the surface to breathe. Hawksbills live in coral reefs where they feed on sponges, sea worms, fish, snails, and crabs.

Green Sea Turtle (Chelonia mydas) – When Christopher Columbus discovered the New World, there were thousands of these turtles in the Caribbean Sea but only a few exist today; the number of individuals has decreased over time. Columbus and other explorers, traders, colonizers, and pirates who later followed his footsteps, quickly realized that this turtle had a very pleasant taste which made it an exquisite dish on the table of many. In those days, sailors easily caught the docile animal and put it on its back, immobilizing it to facilitate the work, in order to keep it on board the ship and kill it when they needed fresh meat. Today, after hundreds of years, the Green sea turtle is still sought and hunted for consumption.

The Green sea turtle is brown, grows to more than one meter long and often weighs over 140 kilograms; it feeds on seagrass from beds near the shore.

Leatherback sea turtle (Dermochelys coriacea) – Leatherback is the largest sea turtle that exists today. It can measure up to 2.4 meters long and weigh 675 kilograms. Its predominant color is black with white spots. The leatherback sea turtle is the only sea turtle that does not have a hard shell. Instead, it is protected by a coriaceous skin which has seven longitudinal ridges. The leatherback is a nomad animal par excellence; its huge front fins allows it to travel thousands of miles. It can nest along the northern coast of South America and then swim toward the north, following the warm stream of the Gulf, along the east coast of North America. It has been seen feeding in places as far away as Nova Scotia, Canada. Its favorite food is a type of jellyfish that most animals try to avoid: siphonophore or poisonous jellyfish. Like all sea turtles, the leatherback has no teeth and instead uses its strong and sharp snout to eat.

Leatherback sea turtle

Leatherback sea turtle

What is the sea turtle hatchery project and what measures does it offer in handling this resource?

Since 1986, a group of biologists from the División de Reservas y Refugios (Reserve and Refuge Division) of the Department of Natural and Environmental Resources of Puerto Rico, worried about the future of sea turtles in our island and began establishing a conservation and scientific research project. Every year from March to November, which is the nesting season for the leatherback sea turtle and hawksbill sea turtle, project staff patrol the beaches of: Piñones, Humacao, and Luquillo, in the morning in search of the characteristic tracks left by turtles when they climb towards the beach to nest. Once a nesting area is identified, it is assessed to see if the nest is in danger of being looted or destroyed by erosion; if so, the eggs are moved by hand which usually exceeds one hundred eggs. Once placed in a container made of polyethylene with a bit of wet sand, these are transported to a hatchery where they are fully protected from anything that threatens to harm them and placed in excavations or artificial nests that are, in shape and measurements, almost identical to those made by the adult turtle, thus simulating the natural nest from where they were collected. After about 60 days of incubation, turtles emerge; ten are taken as a representative sample from each nest and are weighed and measured; once this process ends, all turtles born are counted in order to calculate the reproductive success, which is a ratio between planted eggs and turtles hatched. Later, they are released near the surf zone allowing them to travel a stretch of beach before entering the sea. This reduces possible disruptions to the memories they have of their native beach so that when they are adults they return to the same beach to nest.

All species of sea turtles tend to carry out the process of nesting more than once in a single season; it occurs an average of about six times. After the first turtle nesting, the project staff and volunteers wait 9 to 15 days, depending on the species, before visiting the area at night in order to witness the nesting, protect the animals, mark them, measure them, and collect eggs to transfer to the hatchery, and collect biological information of a quantitative nature.

Since the project began, a considerable amount of new information concerning the current situation, natural history, and nesting beaches has been collected. A total of more than 3,000 baby turtles that have been incubated and protected at the hatchery have been released into the sea during the past three years. The project also established an aggressive educational program disclosing the current status of populations and the importance of its conservation. It is important to protect sea turtles not only because they are an important component of marine life, but because they are part of our cultural heritage. Let us conserve them.

If you witness these events:
° Sea turtle nesting.
° Sea turtle remains.
° Illegal fishing of sea turtles.
° Birth of small turtles.

Please contact:
1. División de Reservas y Refugios … 724-2816
2. Wildlife Refuge in Humacao … 852-6088
3. Resident Biologist, Piñones Forest … 791-7750
4. Cuerpo de Vigilantes … 722-1488/722-4991
5. Puerto Rico’s Coastal Zone Management Program … 725-1155

 

Author: Grupo Editorial EPRL
Published: September 04, 2014.

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