Sea Turtle, Terrapin or Tortoise?

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1 Sea Turtles

2 Sea Turtle, Terrapin or Tortoise? Based on Where it lives (ocean, freshwater or land) Retraction of its flippers and head into its shell All 3 lay eggs on land All 3 are reptiles

3 Freshwater Turtles Soft-shell Turtle Alligator Snapping Turtle Diamondback Terrapin Red-eared Mud Slider

4 Gopher Tortoise Land Turtle

5 Turtle Anatomy Carapace (upper shell) Plastron (lower shell) Scutes (plates that make up the shell) Medial, lateral, marginal

6 Sea Turtle Characteristics Cannot retract flippers, head into shell Salt glands behind eyes secrete salt ( tears ) Nesting females return to the beach where they hatched (summer months) Sex of turtle hatchlings is determined by temperature (warm= female; cool = male)

7 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.

8 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.

9 Sea Turtle Identification 1. Kemp s Ridley 1. Kemp's Ridley Hawksbill 3. Loggerhead 4. Green 5. Leatherback 3. Loggerhead 4. Green 5. Leatherback

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11 Loggerhead Sea Turtle Named for its large head Adults: lbs, carapace about 3 long Main foods are crustaceans, clams, etc Mature in yrs Adults stay close to shore, feed in estuaries or on continental shelf Reddish-brown carapace

12 Loggerhead Sea Turtle Loggerheads are the most common nesting sea turtle in Florida Nests contain eggs One turtle nests 4-7 times per season, every 2+ yrs Eggs incubate for 60 days Hatchlings are long Listed as a threatened species (U.S.)

13 Green Sea Turtle Named for its green body fat Adults: lbs, carapace about 3 long Main food is sea grass Mature in yrs Olive-brown carapace Formerly hunted for soup

14 Green Sea Turtle Nesting green turtles in Florida are federally listed as an endangered species Many green turtles are infected with fibropapilloma virus (herpes virus) Nests contain eggs One turtle nests 2-7 times per season, every 2+ yrs Eggs incubate for 60 days Hatchlings are long

15 Leatherback Turtle Back is covered with leathery skin, with 7 ridges running down the back Largest of the sea turtles - adults are 4-8 long & weigh lbs Main food is jellyfish Can dive to 3000 feet Can regulate body temperature to some degree

16 Some leatherbacks (30-60) nest in Florida each year Nests contain 80 fertile eggs & 30 unfertilized eggs One turtle nests 6-9 times/season, every 2-3 years Eggs incubate for 65 days Hatchlings are 2.5 long Leatherback Turtle Leatherback turtles are federally listed as an endangered species

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18 Hawksbill Turtle Named for its beak Adults: lbs, carapace about 2.5 long Main food is sponges Mature in 3-5 yrs in captivity Patterned carapace Formerly hunted for its shell (tortoiseshell)

19 Nest in the tropics; only a few nests are found in Florida each year Nests contain 160 eggs Hawksbill Turtle One turtle nests 2-4 times per season, every 2+ yrs Eggs incubate for 60 days Hawksbill turtles are federally listed as an endangered species

20 Kemp s Ridley Rarest sea turtle in the world Adult carapace is feet long, weighs # Main food is crabs Shell is olive-gray

21 Kemp s Ridley Nests in daytime Only nests on one beach (Mexico) - mass nesting called arribada (arrival) Each turtle lays 2 clutches per year, each year Nests contain 105 eggs Eggs incubate for 55 days Hatchlings are 1.5 long Federally listed as an endangered species

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23 Early Life Strategies Hatchlings swim out to the Gulf Stream Young turtles are carried around the Atlantic Ocean by oceanic currents for as long as yrs Young turtles are often found in floating mats of Sargassum seaweed (brown algae) Less than 1% probably survive 1 year; 1 in 10,000 may reach maturity

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26 Natural Threats to eggs Raccoons Storms/flooding Threats Predators (of hatchlings) Ghost crabs, sea birds, sharks, fish Predators (of adults) Sharks, killer whales

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28 Human Threats Alteration of beaches/shorelines Artificial lighting Beach driving Fishing gear Boat strikes Poaching Marine debris (plastics, balloons)

29 Conservation Efforts Lighting ordinances Habitat conservation plans Turtle excluder devices (TEDs) Volunteer turtle patrols Satellite tagging

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

32 Archelon Measured 15 ft long (from beak to tail) and 16.5 ft wide (including flippers and shell), weighing 4,500 lbs.

33 Archelon Primarily ate giant squid.

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35 Hatchlings coming out of the Nest

36 Sea Turtle Egg

37 Sea Turtle Nest

38 False Crawl

39 Turtle Tracks

40 Turtle Nest

41 Loggerhead Hatchling

42 Loggerhead Hatchling

43 Loggerhead

44 Loggerhead

45 Loggerhead

46 Nest

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