Helping Endangered Species through Education
Even though sea turtles are an endangered species, man has not stopped stealing eggs, to sell as purported aphrodisiacs, or butchering the adult turtles for meat and oil. Even today, turtle shells are illegally made into unnecessary items like combs and cigarette lighters. Clearly this needs to stop—and education is the key.
Education is the key.
The Sea Turtle Conservation Camp is dedicated to educating especially the children—to teach them the importance not only of sea turtles but all creatures on our earth. The Camp staff, working on behalf of Mexico’s National Commission of Protected Areas, reaches out to the neighboring local schoolteachers and students and has already begun to to educate them on environmental issues. Volunteers and visitors to the Camp also have the opportunity to learn how they can help protect sea turtles.
Eco-tourism is one of the fastest growing aspects of the travel industry. The Turtle Camp offers the possibility to eco-tourists of learning about the work performed by the Camp, participating in patrol of the beach to gather nests, helping to prepare nests for release, and the release of hatchlings.
As the Camp grows, they plan to invite professionals to teach educational programs.
Information About Sea Turtles
Sea Turtles are vertebrates belonging to the Reptile class and Chelonidae family. They are policotherms and ectotherms, so their body activity is dependent on the ambient temperature, and so for this reason the turtles are distributed in tropical and subtropical waters of the world.
There are three species of sea turtle that nest on this beach, with the Olive Ridley being predominant.
Olive Ridley Sea Turtle
Spanish name: Tortuga Golfina
Latin Name: Lepidochelys Olivacea
Status: Endangered
Average Size: 66 cm long and 41 kg
Special Features: Most abundant of all sea turtles
Nesting Period: July to December
Hawksbill Sea Turtle
Spanish Name: Tortuga Carey
Latin Name: Eretmochelys Imbricata
Status: Endangered
Average Size: 91 cm long and 64 kg
Special Features: Its beak is sharp, shaped like a hawk’s beak for feeding on hard coral
Nesting Period: June to July
Leatherback Sea Turtle
Spanish name: Tortuga Laud.
Latin Name: Dermochelys Coriacea
Status: Endangered.
Average Size: 178 cm long and 590 kg.
Special Features: Their top shell does not have scales like the other sea turtles; it is soft and leathery with five ridges running from front to back.
Nesting Period: December to February
Olive Ridley Sea Turtles
Life in the Sea
Sea turtles pass the majority of their life in the sea. Studies using satellite-tracking devices have demonstrated that on average a sea turtle remains 0.03 % of its life cycle on land for reproductive activities and the other 99.97 % of the time is spent in the sea. Of course, this is only the case for the females; the males never leave the sea. The majority of studies on the sea turtles, however, have centred on the time spent on the beach. Therefore, there is still little understood about the mechanisms of orientation and navigation in the open sea through which the Olive Ridley sea turtles return to the same beach on which they were born to nest, migrating 1000’s km between their feeding grounds to these nesting beaches.
There are several proposed mechanisms of orientation and navigation for the Olive Ridley sea turtles:
• Chemo sensitivity: The ability to detect very small concentrations of chemicals from the nesting beach in the water. Indeed this phenomenon has been demonstrated in the Green turtles (Chelonia mydas).
• Wave Sensitivity: The ability to utilize geo-magnetic fields of the Earth, distinguishing between maximum and minimum fields in the bottom of the ocean that occur in areas of dispersion of the marine plates. This idea is supported by the knowledge that nesting beaches are situated in areas of energy discharge and elevated magnetism.
• Genetics: Studies on the DNA of a population of Green turtles (Chelonia mydas) that nest exclusively on Ascension Island have shown homologies between the DNA of this population that are different to other colonies of Green sea turtles.
Feeding and Nutrition
Olive Ridley sea turtles are facultative carnivores. They will feed on whatever is available, and studies in Mexico assessing the stomach contents of these animals have demonstrated a varied diet of fish, jellyfish, crustaceans, molluscs, algae, fish eggs and marine maggots.
Reproduction
This species of sea turtle usually migrates along the continental platforms, feeding in shallow waters, and converging in the summer and autumn for nesting on beaches in tropical continents. Olive Ridley sea turtles reach sexual maturity at 7 to 9 years old, and approximately 60 % of the population nest annually, 29 % every 2 years and 11 % every 3 years, the frequency being affected by the amount of food available and the distance of migration between feeding and reproductive grounds.
At the start of the nesting period, the groups congregate and direct themselves towards their respective nesting beaches; initially the females arrive, shortly followed by the males. Sexual reproduction generally occurs near the nesting areas. The male embraces and holds the female strongly below him, utilizing his anterior fins and in moderation his posterior fins, his penis protrudes from his tail and is inserted into the female, and they remain in this way for 2 hours. One female can mate with many males before moving to the beach for egg laying.
Nesting
After mating the females move to the nesting beach to lay their eggs. The nesting of Olive Ridley sea turtles can be divided into the following phases.
1. Emergence
The sea turtles emerge from the water, encountering the beach, and search for a nesting site.
2. & 3. Excavation
Turtles dig a ditch in which the eggs will be laid. Initially, (stage 2.) all the fins are used to form the ditch, and in the final phases (stage 3.) the form and depth is achieved using the posterior fins in a manner of small shovels for digging and compacting the sand.
4. Egg Laying
Whilst egg laying, the turtles remain immobile and can be measured or marked and eggs can be collected by man. The eggs fall into the hole in groups of 2 or 3 eggs at regular intervals accompanied by protective mucus, which contains an active anti-bacterial agent. During this phase the anterior fins of the turtle are totally extended and the posterior fins are gracefully extended flanking the mouth of the nest. Each Olive Ridley sea turtle lays an average of 105 eggs per nest. Each egg is white, about 40 mm in diameter and 39 g in weight; they look very similar to table tennis balls.
5. Covering Up
After the egg laying is completed, the females commence to cover up the nest, introducing and compacting sand with its posterior fins and throwing at the same time sand with its anterior fins. Finally, the turtle compacts the whole nest with its whole body weight, producing a peculiar sounds in the beach. Before leaving the female walks several times over the nest, hiding the tracks and the exact location of the site.
6. The Return
At the end of the process the female returns to the sea. The average duration of the process for the Olive Ridley species is about 1 hour.
