Coral Cay volunteers help protect Leatherback turtles in Tobago
Added to website: 30 May 2007
Coral Cay Conservation has recently endeavoured on an exciting new collaborative project in Tobago in an effort to help monitor and protect the endangered marine turtles laying their eggs on the beaches of Tobago. Tobago is one of the few remaining places in the world where female Leatherback turtles (Dermochelys coriachia) come ashore to nest. Endangered Hawskbill turtles (Eretmochelys imbricate) and Green Sea Turtles (Chelonia mydas) also nest along the same beaches.
Leatherback turtles
Leatherbacks are the largest and most endangered of the marine turtles. They are also some of the most ancient creatures ever to have crawled this planet. Having outlived the dinosaurs, Leatherback bones have been found from 100 million years ago! Leatherbacks are the largest turtle, reaching a shell length of 1.7m and a mass of 700kg. They are named after their rubbery, dark shell or carapace marked by seven narrow ridges that extend along the length of their back. As adults, their diet consists solely of jellyfish and other related sea-organisms. Their migratory routes take them as far north as Newfoundland and as far east as Africa, bringing them into local waters only during the mating and nesting season (April - September). Due to their immense size, the Leatherback’s only natural predators are sharks and man. There are many places throughout the Caribbean and Latin America regions where Leatherbacks are regarded as inedible. Unfortunately, in Tobago, Leatherbacks are still seen as a traditional food source and poaching during the closed season remains a huge threat to the species.
Threats to Leatherback turtles
Leatherback turtles are threatened by human impacts from the minute they manage to break through the safety of their egg. Scientists estimate that only 1 in 1000 leatherback hatchlings survive to adulthood. Tourists walking along the beaches compress the sand, and as a result, the hatchlings have to put in more effort and spend more time clawing their way up to the surface. When the exhausted turtles do make it up to the top, they face their next challenge – reaching the safety of the sea! Attracted to the reflecting moonlight, baby turtles instinctively crawl in the direction that is lit up most. Light pollution caused by near shore construction of resort hotels means that the ocean is just a shadow in a 500 watt light beam directed onto the beach. Some turtles have been seen crawling around parking lots and into swimming pools. In addition to the natural predators such as gulls and herons, there is the threat of scavenging or playful dogs that intercept the turtles on their way down to the water.
Even a minor obstacle like a fishing boat can prevent hatchlings from reaching the sea. Leatherbacks are particularly vulnerable to this as they use the same nesting site each year and the offspring return to these sites when they reach maturity. When they hit the beach Leatherbacks go into a trance-like state and are on a set course up the beach that has proven successful and unchanged over hundreds of years. This allows them to preserve their energy and bodies temperature balance. A turtle will continuously attempt to crawl against a beach chair or fishing boat until it is over-exhausted.
Once the hatchlings have reached the ocean, they may be caught in drifting nets or other garbage. Some still struggle to find their bearings in the water as more light pollution from jetty’s and peninsulas may send them off in the wrong direction. Although we know very little about the turtles’ oceanic behaviour, adults are often found floating on the surface or caught in longlines or fishing nets. On closer examination, some have been found with stomachs full of plastic bags, mistaken for jellyfish.
Adult females have the potential of nesting up to 10 times a season and return every 3-4 years for over 20 years. Nesting females are threatened by poaching and disturbance from humans. Flashlights, noise, obstructions and flash photography all disturb and increase stress, decreasing the chances of laying a successful brood. Turtles are protected by Tobagonian law which states that that no person shall catch, kill or sell any turtle during the nesting season (1st March to 30th September). It further bans turtle hunting within the nearshore or reef throughout the rest of the year as well as making the possession and sale of turtle eggs illegal year-round. Unfortunately, illegal poaching still occurs. The good news is that many beaches in Trinidad and Tobago are now patrolled regularly. Resort hotels are now more willing to cooperate and do their bit. Local people are seeing the importance of helping to protect the Leatherbacks. This awareness is essential to effective turtle management and preservation.
What is Coral Cay doing and how can you get involved?
Together with the Save Our Sea turtles (SOS), a local initiative to protect nesting turtles, CCC is providing much needed man power to help patrol the beaches that are popular nesting sites for turtles. Coral Cay will also be helping SOS with community educational projects. The egg laying occurs at night and it is during this time that volunteers get the unique opportunity to patrol along the moonlit beaches on the Caribbean side of Tobago in search of the leatherbacks. When one has been spotted, the first aim is to keep the on looking tourists a good distance away from the female as she slowly makes her way up the beach in search of a sandy patch where she can start digging her nest. Curious onlookers are kindly informed about the importance of not disturbing the soon-to-be mother. It has been shown that the time it takes the female to complete the process of digging, laying and covering up is directly related to the number of people watching her. Females, especially young, inexperienced individuals may spend over an hour concealing the eggs if she feels that they are threatened by the spectators.
Once the eggs have been laid, the female is carefully approached by the guide and a volunteer and the eggs are counted, the mother is measured up and a tag may be applied in order to monitor where and when the individual is returning.
The female will spend anywhere between 30 minutes to an hour and a half covering up the eggs and ensuring that no traces remain of her activities. She will then start making her way back to the safety of the water, exhausted but content in the knowledge that one day her offspring will hatch and eventually use the same beach to secure her species’ survival, with a bit of help from a few dedicated conservationists!
For more information, please click on the following links:-
Save Our Sea turtles (SOS) - A local organisation dedicated to protecting the sea turtles that inhabit and nest around Tobago
Marine Turtle Research Group based at the University of Exeter
Great Turtle Race - A collaborative project between NGO and the government of Costa Rica that tracks Leatherback turtle’s movements form Costa Rica using satellite tagging. You can join in and follow the turtles over two weeks as they make their way to the Galapagos Islands!
The Leatherback Trust - A non-profit foundation established to save the leatherback turtle and other sea turtles from extinction.
All images are taken from Save Our Sea Turtles website
