Sea Turtle Biology and Conservation Sea Turtles

Sea Turtle Biology and Conservation

Sea Turtles in Mythology • Turtles have long been revered in myths. • Most Indian tribes see turtles as being sacred. • The are seen as being supernatural because of their powers for survival. • The Greeks saw turtles as standing for wisdom.

More Sea Turtle Myths • In a Chinese myth, a turtle was believed to have developed the world within its shell. • Some Indians believe that the world in which we live was formed on the back of a turtle.

Sea Turtles are still important in human culture today.

Sea Turtle Identification

Green Turtle • Most common species of sea turtle. • It’s called the green turtle because of the green color of the fat under shell, they are not actually green.

Green turtle • It is one of the largest species of sea turtles: 3 ft long, up to 300 lbs. • Green turtles can be recognized because they have one pair of scales in front of their eyes, instead of 2, like most sea turtles

Black turtle • Black turtle is named for the black/gray color of its shell. • It is primarily located in the Eastern Pacific, and is protected in the Galapagos and some areas of Mexico.

Flatback Turtle • They are named Flatback because of their flattened shell. • Flatback Sea turtles are only found in Australia.

Loggerhead Turtle • Loggerheads can grow up to 350 lbs, between 31 -42 ins. • They can be identified by their large head, reddish brown carapace (top), and dull brown plastron (bottom).

Hawksbill Turtle • The beautiful shell of Hawksbill turtles is often used for jewelry

Olive Ridley • This is one of the smallest sea turtles, weighing only 100 lbs. It is also one of the most numerous species of sea turtle. • It is named Olive Ridley because of the olive coloring.

Kemp’s Ridley • Kemp’s Ridley is the most endangered species, as well as the smallest: only grows to 24 -28 ins and 77100 lbs. • They are olive green in color. • They only nest on one beach in the world, in Rancho Nuevo, Mexico.

Leatherback • Can dive the deepest and travel the furthest of any other turtle. • They have tough leathery skin covering their back.

Leatherbacks • Largest sea turtle, up to 7 ft long, 1200 lbs. • Instead of a solid shell they have bones in their skin that form 5 ridges.

Navigation

Navigation • Navigation is finding the way from one location to another. • What are some ways that people can navigate?

Navigation • 1. Compass • 2. Stars • 3. Position of Moon and Sun • 4. Maps • 5. Landmarks • What are some ways that sea turtles may navigate in the water and on land?

Navigation • • Sight Position of the moon Wave direction Internal compass (turtles that we know use this: loggerhead and leatherback)

Navigation • So how do you think baby turtles navigate from the nest to the ocean?

Navigation • 1. Move away from silhouettes at the top of the beach • 2. Orient themselves toward the brightest light (moon on water in low populated beaches) • They can sense the direction of waves when in the water • Some use a magnetic compass.

Navigation • What are some reasons a turtle might have to navigate in the ocean? • How far do you think turtles may migrate?

Navigation • • They migrate to find: food mates and beaches to nest on

Navigation • Some turtles migrate over 2600 km but most will only travel 1000 km.

Reproduction

Reproduction • Turtles lay eggs in nests on the beach, usually at night. • They can lay up to several hundred in one nest. • Many turtles can create several nests over a few weeks, during the reproductive season.

Reproduction • After laying all their eggs, the female turtles return to the ocean. • After sixty days the baby turtles will emerge and travel to the ocean, and must defend themselves.

Conservation • 1. What is making the sea turtles endangered? • 2. How can we protect turtles and their habitats? • 3. Problems being faced with enforcing laws. • 4. What can we do?

1. What is making the sea turtle endangered? • Coastal development • A. Destroying nesting beaches. • B. Increasing pollution in bays. • C. Distracting hatchlings with light. • D. Beach vehicle activity.

1. What is making the sea turtle endangered? • Net & Shrimp trawls • A. Entanglement and drowning. • B. Used in trade for shell and meat. • C. Destroying feeding grounds.

1. What is making the sea turtle endangered? • Industrial development • A. Sand walls preventing nesting • B. Oil spills • C. Damage to coral reefs and sea grass beds.

1. What is making the sea turtle endangered? • Natural Mortality • A. Predation as hatchlings • B. Predation as juveniles and adults • C. Old age

2. How can we protect the turtles and their habitat? • Protect nesting grounds • A. Reserves and wildlife refuge • B. Relocate eggs to hatcheries. • C. Patrol the beaches from poachers • D. Prevent coastal development and activity.

2. How can we protect the turtles and their habitat? • Education • A. Get locals involved • B. Decrease international trade of products • C. Scientific research • D. Tell others

2. How can we protect the turtles and their habitat? • Improvements • A. Improve fishing trawls (TED) • B. Protect with turtle farms • C. Decrease pollution and trash • D. Get involved

3. Problems being faced with enforcing laws • Not all countries have the money or manpower to control poaching on beaches. • Violations of poaching may only face a simple fine, or may be disregarded.

3. Problems being faced with enforcing laws • Jurisdiction varies between governmental agencies: • water = fishery depart. • land = wildlife and forest depart.

3. Problems being faced with enforcing laws • Turtle farms for trade and reinstatement cost millions of dollars and take 20 to start. • “to some people. . . trade and conservation appear to conflict, but if properly applied, they could well be the key to surviving the species” • --H. Reichart

3. Problems being faced with enforcing laws • Local people are not educated enough in rural countries and need turtle meat as a source of protein. • Not all nesting beaches can be protected.

4. What can we do as students? • We can do our part in conservation by simple acts: • 1. Picking up trash on the beach. • 2. Cutting soda 6 -pack rings, and recycle • 3. Don’t buy marine animal products and souvenirs • 4. Be careful what food we eat.

4. What can we do as students? • We can go further by: • 1. Volunteer in helping scientists do research. • 2. Adopt a turtle. • 3. Become members of animal conservation societies. • 4. Write to your Congressman.

Interesting Facts: Archelon is the oldest known fossil at 150 MYA. Found in 1970’s in S. Dakota.

Archelon: Measured 15 ft long (from beak to tail) and 16. 5 ft wide (including flippers and shell), weighing @4, 500 lbs.

Archelon: Primarily ate giant squid.

Photo Credits • • www. cccturtle. org: #1, 7, 11, 16, 17, 19, 24, 29, 37, 42 www. co. broward. fl. us/bri 00600. htm: #5 www. yoto 98. noaa. gov/books/seaturtles/seatur 1. htm: #6 www. ex. ac. uk/telematics/Euro. Turtle/homep. htm: #8, 10, 12, 14, 18, 20 www. baja-tortugas. org/conservation. html: #13, 26, 32, 36, 38 www. bonairenet. com/turtle. htm: #10, 15, 21, 49 www. seaworld. org/Sea_Turtle/seaturtle. html: #23, 41, 47 www. nps. gov/pais/turtles. htm: #25

Photo Credits cont. www. turtle. ky: #43, 46 Webhost. bridge. W. edu/Esand. G/blkbeach. htm: #45 www. itec. edu. org/conservation. html: #8, 22, 48 J. Ripple. 1996. Sea Turtles. Voyageur Press: #33, 35, 39, 40, 44 Jeff Seminoff: #9 John R. Hendrickson: #4, 27, 28, 30, 34 Hometown. aol. com/gonyosoma/folklore. html: #2 www. bonairenet. com/turtle. htm: #9, 10 www. bhigr. com/pages/info-rept. htm: #50, 51, 52