Saturday, May 1, 2010

Leatherback Sea Turtles are BACK

Leatherbacks, besides being the largest sea turtles in Vieques and the world, dive deeper, have warmer body temperatures, widest ranging migration, have the oldest evolutionary roots, and are more numerous than any other sea turtles. At 4 to 8 feet, the adult leatherback can reach weights of 500 to 2000 pounds. Giants of the sea they remain in size, habits and history.

These reptilian relics were once prevalent in nearly every ocean. Yet worldwide, female leatherbacks have decline more than 50% in the last thirty years. These days, small nesting populations in Puerto Rico range from 30 to 90 females a year—with an estimated 19 to 37 females expected to nest on Vieques beaches this season.

Unlike other sea turtles seen in Vieques’ waters, the leatherback’s shell is rubbery-like, not bony hard like all other species. Ridges along the leatherback’s flexible shell give it a more hydrodynamic structure, helping them to dive up to 4,200 feet/1,280 meters deep, and for up to 85 minutes. They have been officially listed as endangered since 1970.

Sadly, plastic bags at sea look like leatherback’s favorite food: jellyfish. They also feed on sea urchins, squid, crustaceans, tunicates, fish, blue-green algae, and floating seaweed. As much as eleven pounds of plastic has been found in the stomach of a single leatherback. Plastic can block their ability to digest, and they starve. These inky blue carnivores can live up to 45 years, if they do not fall victim to humans, directly or indirectly.

Vieques’ National Wildlife Refuge biologist Mike Barandiaran said, “How can we not have deep respect for these amazing creatures who grace our waters and beaches. Their ancestors go back more than 100 million years.”

Along with Mike and the Refuge, Julian Garcias’ group TICATOVE is tracking and studying local leatherbacks with the help of volunteers trained by Mike Evans, the manager at Sandy Point Nat. Wildlife Refuge (Saint Croix), and others at their long-established leatherback program.

A new set of community volunteers have recently attended their first training. Volunteers are critical especially since the only two biologists assigned to Vieques were let go by the Commonwealth Government. This included, “Erick Bermudez, who continues to work hard with me in the conservation of these endangered species,” said Julian Garcia, President of TICATOVE. “We are grateful for the grant support received this year from Biologist Carlos Diez, Coordinator of PR Sea Turtle Conservation Project in the Department of Natural and Environmental Resources.” Because of this grant TICATOVE members will be providing more assistant to the valiant conservation work being done in the DNER Natural Reserve Puerto Mosquito Biolumnest Bay and municipal areas by Edgardo Belardo.

Monitoring and patrolling is critical to protecting nests and baby sea turtles, and the new volunteers are working with more experienced members to protect these giants of the sea that are currently nesting on our beautiful island.

“Everyone on the beach can do their part by not disturbing nests, which helps maximize hatchling survival,” reminds Julian. “Do not disturb stakes on the beach and avoid stepping on nesting sites. Please do not let domestic animals run loose on the beach, and do not consume turtle products.”

Making Baby Leatherbacks: FACTOIDS
• Leatherbacks reach reproductive maturity earlier than most other sea turtles.
• They mate at sea when females are about 9 -15 years old.
• Females come ashore to lay their eggs.
• Females nest an average of 5 to 7 times within a single mating season.
• Their eggs are laid almost always at night in clutches of about 60 – 120 eggs.
• After incubating for 60 to 65 days, hatchlings emerge usually at night.
• Nest building leaves a large area of disturbed sand, when the female disguises the nest.
• Females return to the nesting beach areas they sprang from every 2-3 years to lay their eggs.
• Variable temperatures inside the nest determine the sex of the hatchlings: as in “Hot girls and Cool guys.”

Why Are There Less Leatherbacks Today? MORE FACTOIDS:
• Humans: exploit them for their eggs and their meat;
• Fishing: they get caught in nets, trawlers, lines and gears used by commercial fisheries;
• Coastal Development: nesting habitat is lost or degraded;
• Beachfront Lighting: disorients hatchlings;
• Other Animals: native and non-native predators (including mongoose and dogs off leash on the beaches) eat eggs and baby turtles.
• Food Depletion: degradation of their foraging habitats;
• Floating Trash: marine debris and trash at sea, ends up in their stomachs; and
• Accidents: they are hit by watercraft, commercial and personal.

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