Sea Turtles: Seven different species Their impact on humankind What is causing their extinction? What is being done to prevent further extinction?...
The Green SeaTurtleThe Green Sea Turtle is one ofthe largest and most widespreadof all marine turtles.The oval carapace varies fromolive to brown, grey and blackwith bold streaks and blotches,but the common name GreenTurtle is derived from the greencolor of the fat and connectivetissues of this species.Males are generally smaller thanfemales and the green turtlediffers in appearance from othermarine turtles by the possessionof a single pair of scales in frontof the eyes and a serrated bottomjaw.
Hawksbill SeaTurtleThe critically endangeredHawksbill turtle has beenexploited for thousands of yearsas the sole source of commercialtortoiseshell.The beautiful carapace isgenerally streaked and marblewith amber, yellow, or brownand often has a strongly serratededge.The strongly hooked beak on thenarrow head gives rise to theHawksbill turtle’s commonname. Unlike other marineturtles, the scales (scutes) of theHawksbill turtle’s carapace areimbricate, or overlapping.
Flatback Sea TurtleThe Flatback Sea turtle isdistinguished by its restricteddistribution and its very flatcarapace.The fleshly carapace, which iscomposed of thin, bony scales,has an upwards turned rim,particularly toward the rear.The Flatback Turtle has one ofthe most restricted ranges of anymarine turtle, it is found only inthe tropical waters of northernAustralia, and Papua NewGuinea, and only nests inAustralia.
Loggerhead SeaTurtleThe Loggerhead Sea Turtle isthe most migratory of the marineturtles, with individuals knownto cross the Atlantic, and Pacificoceans.Their name comes from its largehead, that contains verypowerful jaws.Loggerhead Sea Turtles are themost common sea turtle found inthe Mediterranean, and westernNorth Atlantic Ocean.
Kemp’s Ridley SeaTurtleThis turtle is the world’s mostendangered sea turtle, with aworldwide female nestingpopulation of a roughlyestimated 1,000 individuals.Their slow decline has beencaused by the over-harvesting oftheir eggs over the past centuryand have not been able torebound.They are also one of the smallestsea turtles.
Olive Ridley SeaTurtleThe Olive Ridley Sea Turtle is thesmallest of the sea turtles, only 50-75cm.The Olive Ridley Sea Turtle can bedistinguished from the closelyrelated Kemp’s Ridley Sea Turtle byhaving more than 5 bony plates, orscutes, running the length of thecarapace; Kemp’s Ridley Sea Turtlesonly have 5.This type of Sea Turtle is mostlyknown for its nesting habits. Anarribada occurs while nesting,which is the congregating of manythousands of females on the samebeach at the same time.
Leatherback SeaTurtle(DermochelyidaeFamily)The Leatherback Sea Turtle isthe largest of all living turtles,145 to 160 in length.The Leatherback Sea Turtle hasno visible shell. The shell ispresent but it consists of bonesthat are buried into its skin.The Leatherback Sea Turtle alsofeed in waters much colder thenother marine turtles can handle.They have a network of bloodvessels that work as a counter-current heat exchanger; a thickinsulating layer of oils and fatsin their skin, and are able tomaintain body temperaturesmuch higher than theirsurroundings.
The Basics aboutSea Turtles:Anaerobic system of Respiration.Most Sea Turtles have a lifeexpectancy of 80 years, but canlive much longer.Sand temperature determines thegender of the baby hatchlings.Lighter sands maintain highertemperatures, which decreasesincubation time and results inmore female hatchlings.Just behind each eye is a saltgland. The salt glands help seaturtles to maintain a healthywater balance by shedding large“tears” of excess salt.
The Importance of Sea Turtles toHumankind The Moche people of Sea Turtles, especially ancient Peru worshipped Green Sea Turtles, are the sea and its animals. one of the few animals They often depicted sea that eat sea grass. turtles in their art. Sea Turtles enjoy They help keep dunes immunity from the sting and beaches from of the deadly box jellyfish, becoming eroded with and regularly eat them, the nutrients gained helping to keep tropical from baby hatchlings. beaches safe for humans.
Continued…Sea Turtles also serveentertainment purposes such asin the movie Finding Nemo.In Finding Nemo we areintroduced to an 150 year oldEastern Pacific Green Turtlenamed Crush.The popularity of this characterhas resulted in the Disney themeparks to create an exhibit called:Turtle Talk with Crush.Turtle Talk with Crush
The Slow Extinction of Sea Turtles (Natural Occurrences)- Natural threats are common in the animal kingdom. Sea Gulls, and crabs are the main surface predators for young hatchlings. Once the hatchlings reach water, Tiger Sharks and other marine life become the predators. Once the hatchlings reach maturity, they are immune to predator attacks, and instead are killed-off by the actions of humans.
Food Source: Although Sea Turtles have spiritual or mythological importance in many cultures around the world, this has not prevented humans from consuming their eggs or meat. In many coastal communities, especially in Central America and Asia, sea turtles have provided a source of food. During the nesting season, turtle hunters comb the beaches at night looking for nesting females. Often, they will wait until the female has deposited her eggs to kill her. Then, they take both the eggs and meat.
Luxury Items: Hawksbill sea turtles, recognized for their beautiful gold and brown shells, have been hunted for centuries to create jewelry and other luxury items. As a result, these turtles are now listed as critically endangered. Scientists estimate that Hawksbill populations have declined by 90% during the past 100 years. While illegal trade is the primary cause of this decline, the demand for shells continues today on the black market. The lack of information about sea turtles leads many tourists to unwittingly support the international trade in these endangered species.
Debris: It is estimated that more than 100 million marine animals are killed each year due to plastic debris in the ocean. More than 80% of this plastic comes from land. The plastic washes out from our beaches and streets. It travels through storm drains into streams and rivers. It flies away from landfills into our seas. As a result, thousands of sea turtles accidentally swallow these plastics, mistaking them for food. Leatherbacks especially, cannot distinguish between floating jellyfish, a main component of their diet, and floating plastic bags.
Continued: Besides the causes mentioned, these too cause sea turtle extinction: Commercial Fishing, Artificial Lighting, Coastal Armoring, Beach Dredging, Climate change, and marine pollution such as oil spills.
What is being done to preventfurther sea turtle extinction? TED’s- Turtle Excluder Devices have reduced sea turtle bycatch in shrimp nets by 97%. The use of the devices ideally allow all bycatch larger than ten centimeters to escape the nets unharmed. This selectivity is achieved by metal grids integrated into the trawl net structure. The grids act as a barrier for large creatures such as turtles from passing through the bars into the back of the net. A small opening in the net is then available either above or below the grid so that creatures that are stopped by the TEDs are allowed to escape the net, relatively unharmed. Targeted species such as shrimp however, are pushed to the back of the net.
Continued…: Besides TEDs simple things such as recycling, and if you live near coastal lines to turn off outdoor lights from May 1st to October 31st (the mating season) Along with these simple solutions, sea turtle conservation is another way to help the decline. Three companies in particular are helping to conserve sea turtles: The WWF, the STC, and Disney.
The World WildlifeFoundation (WWF)Conservation Efforts to Protect Promoting regional and international agreements toturtles: Effective conservation conserve marine turtles.requires protection at all stages Lobbying for turtle-friendly fishing practices, such as theof the life Cycle. The WWF is use of TEDs in nets.working around the world to Halting the illegal trade of turtle meat and eggs, throughconserve marine turtles by: TRAFFIC, the wildlife trade monitoring networkEstablishing and strengthening created by WWF and IUCN.protected areas around nestingbeaches.Raising awareness andpromoting ecotourism at marineturtle sites, so that localcommunities become involved inand benefit from protectingturtles and their nests.
The Sea TurtleConservancy (STC)Through sea turtle research, Habitat Protection: The Sea Turtle Conservancy programconservation and advocacy, STC work to enact protective laws to establish sanctuaries for sea turtles. Through environmentally-sound tourism,is addressing the threats to sea visitors experience nature without harming it, andturtles and the natural habitats enhance the economies of local communities.upon which they depend. Advocacy: The STC monitors numerous state, national, and international issues affecting marine turtles. As issuesOne can chose to make a small arise that pose a threat to turtles, their experts intervenedonation of $25 to become a with appropriate direct action.member of STC and will ensure Research: Over four decades of scientific study sponsored bysea turtles are swimming free in the STC has generated essential data about endangeredoceans for future generations. species and their habitats and has advanced the world’s understanding of the ancient and enigmatic sea turtle. Education: The STC works with members, coastal residents,With the donated money, STC conservationists, and governments to increase awarenesshelps fund many programs… about sea turtles and the threats facing them. Education is the first step toward effective and long lasting protection of endangered species.
DisneyLastly, Disney is helping toconserve sea turtles by making Surprisingly, very little information is known about theefforts at tracking sea turtles. movement patterns of juvenile sea turtles. Once hatchlings leave the nesting beach, it is very difficult forThe Walt Disney World Animal scientists to document where these turtles spend theirPrograms team has been involved time. However, recent advances in technology have madein sea turtle rehabilitation formany years. To date, the Seas team it possible to learn more about the habitats of juvenilehas cared for and released more sea turtles. Telonics, Inc., a manufacture of telemetrythan 200 turtles. Most of the turtles devices for monitoring wildlife, has produced a satellitethat find their way to Walt DisneyWorld are animals that have been transmitter that is now small enough to be carried byrescued by various organizations juvenile sea turtles. In collaboration with the Archieand come to them with medical Carr Center for Sea Turtle Research at the University ofchallenges. A majority of theturtles suffer physiological Florida, the Seas and Disney’s Animal Kingdom, we areproblems attributed to extended testing the first satellite transmitters for use on juvenileperiods of time in cold water. sea turtles that measure approximately 30-40cm.These cold stunned turtles arerescued, rehabilitated at the Seas,and than released under thesupervision of the Florida Fish Sea Turtle Trackingand Wildlife ConservationCommission.
Conclusion: If anyone would like further information about sea turtles, or how to do your part in saving this beautiful and majestic creature visit the following websites… www.worldwildlife.org/species/finder/marineturtles/marine turtles.html www.conserveturtles.org/stctmp.php www.tourdeturtles.org/2011/sponsors.php