Leatherback Sea Turtle Dermochelys coriacea

Jordan Taylor2-10-14

“A hypocrite is the kind of politician who would cut down a redwood tree, then mount the stump and make a speech for conservation.”

Adlai E. Stevens

Bio:• Life History• Physical Characteristics• Reproduction• Diet• Habitat• Territory & Range• Behavior• Predators• Parasites• Diseases• Endangered, Why?• Status• Conservation Management• Chain Reaction

Hatchlings: Adult female nests She returns to the sea Developing hatchlings do not have sex chromosomes

Gender is determined temperature Mix of Males/Females-

“Pivotal” temperature- 83-85 degrees Fahrenheit

Females- Hotter temp

Males- Colder temp

After 45 to 70 days- Break out of eggs Caruncle: Temporary tooth located on their snout Remain in the nest Absorb yolk, attached by umbilical to their abdomen Provides energy for first few days, to the nest to offshore waters Remain until the temperature of the sand cools Less likely to be eaten by predators or overheat at night Clues to find the water including:

Slope of the beach White crests of the waves Light of the ocean horizon

Life History:

Juveniles: Size of dinner plates Return to coastal until they reach sexual maturity

(adulthood) Feed over enormous areas-

Shallow waters Sexual maturity-

15 years Leave coastal areas/migrate Thousands of miles To breeding areas to mate

Life History: Cont.

Adults: Females-

Nesting- Come ashore to lay eggs Wait for darkness before leaving water Digs nest with rear flippers 100 or more ping-pong ball sized eggs May take a few hours or more Cover and disguise nest before returning to water Never sees hatchlings once born Six weeks to two months later

Nesting season ends- Return to hunting grounds Not nesting again 2 to 3 years Continue to mature 30 year in captivity 50-70 year old in wild May live a century

Life Cycle: Cont.

Largest sea turtles 4 to 8 feet in length 500 to 2000 pounds Shell-

small bones covered by rubbery skin with seven longitudinal ridges or keels

Skin- Black with pale spotting Pink spot on the dorsal surface of the head in adults Paddle-like clawless limbs: black with white margins/pale spotting.

Jaw- Tooth-like point located on each side of the gray upper jaw lower jaw is hooked

Physical Characteristics:

Nesting- March to July 5 to 7 times 11 nests 9 to 10 days of Constructs at night in clutches with an average of 80 to 85 eggs Eggs 2 inches in diameter Incubation takes 55 to 75 days

Hatchlings: Hatch at night Return to their nesting beaches every 2 to 3-years Sexual maturity about 16 years Coloration-

Black with white flipper margins and keels

Significant Nesting Areas- Caribbean-

Puerto Rico U.S. Virgin Islands

Southeast Florida Largest Nesting Areas-

Northern South America West Africa

Reproduction:

Jellyfish Sea urchins Squid Crustaceans Tunicates Fish Blue-green algae Floating seaweed

Diet:

TunicatesSea urchins

Crustaceans

Habitat: • Beaches:– Deep water– Rough seas– Vegetation– Sloped- Safe distance from dry sand and water

Distributed worldwide in tropical and temperate waters of the Atlantic, Pacific, and Indian Oceans

Small numbers far north: British Columbia Newfoundland the British Isles

Small numbers far south: Australia Cape of Good Hope Argentina

Recent estimates for the North Atlantic: Range of 34,000 to 94,000 adult

Territory & Range:

Independent Migrate:

Great distances between nesting and feeding grounds

Located: High concentrations of jellyfish Feed near the surface Highest concentrations of prey

Behavior:

Predators: Humans- #1 predator Eggs:

Lizards Birds-

Knots Plovers Raptors

Mammals- Raccoons Dogs

Hatchlings: Cephalopods Sharks Large fish

Adult leatherbacks: Jaguars Killer whales Large sharks

Predators:

Piping Plover

Red Knot

Cephalopods

Conchoderma virgatum: Species of barnacle Not Harmful

Parasites:

Fibropapilloma- Water pollution

Tumors Found on Body: Lungs Kidneys Liver

Causes: Oil spills Runoff- Chemicals Fertilizers Toxic waste

Destroys food sources: Aquatic plants Animals

Diseases:

Once the world’s largest population Exploitation by humans:

Eggs meat Commercial fisheries/Over harvesting Long-line fishing- Long fishing line with multiply hooks

Other factors: Loss of nesting habitat from coastal development Confusing hatchlings by beachfront lighting Native predators/non-native predators Marine pollution/debris Watercraft strikes

Endangered, Why?:

Long-Line Fishing

Difference in Hooks

Long-Line Hooks Circle Hooks

Delaware: Seen in the Chesapeake Bay Less frequently the Delaware Bay Habitat loss/ change Continues loss of open space to development

Federal: Registered June 2nd,1970 Endangered through out range

Listed endangered both state & federal governments

Status:

Increase hatchling populations: Southeastern U.S. and U.S. Caribbean-

Nest protection efforts/beach habitat protection Reduce leatherback deaths from long-line fishery Coastal counties/communities have developed lighting regulations U.S. nesting beaches continue for long-term protection

Pacific coasts of- Mexico Costa Rica Other Central American countries

Eliminating Long-Line Fishing: WWF-

Working with fisheries to switch to more turtle-friendly fishing hooks ("circle" hooks) Satellite devices:

Tracks turtle movements

Conservation Management:

Leatherback sea turtles are predators: Affect prey population densities is unknown Might have been important before their

populations were reduced by harvesting Leatherback eggs and hatchlings:

Food source for egg predator populations

Chain Reaction:

All In All…

• Populations decreasing• Support conservation groups• Stop pollution• Encourage local fisherman to be apart of

conservation • Effect our eco-systems• Encourage others• Spread the word• Be involved in local conservation projects

http://www.fws.gov/northflorida/seaturtles/turtle%20factsheets/leatherback-sea-turtle.htm

http://worldwildlife.org/species/leatherback-turtle http://www.nmfs.noaa.gov/pr/species/turtles/leatherback.htm http://conserveturtles.org/seaturtleinformation.php?page=leatherback http://www.seeturtles.org/915/leatherback-turtle.html http://www.turtles.org/leatherd.htm http://animaldiversity.ummz.umich.edu/accounts/Dermochelys_coriac

ea/#behavior

http://people.wcsu.edu/pinout/herpetology/dcoriacea/conservation.html

http://www.delawareonline.com/article/20060512/LIFE/605120326/Delaware-home-15-species-turtles

Resources: