1. Marine Turtles

2. Marine Reptiles Some reinvaded the oceans, but still breathe air:
Turtles (Order Chelonia)
Snakes (Order Squamata)
Iguanas (Order Squamata)
Crocodiles (Order Crocodilia)
Saltwater crocodile
Marine turtle
Marine Reptiles (Sea Snakes)
Marine Reptiles include sea snakes, saltwater crocodiles, marine iguanas and sea turtles. Sea snakes are a group of true snakes that have completely adapted their life-histories to live in the sea.
Sea snake
Marine iguana

3. Marine Reptiles
Ectotherms (“cold-blooded”), so mostly in warmer waters, seasonal in temperate waters
Cold stunning –
Turtles too far north when water temperature suddenly drops (<50°F)
Get lethargic, immobile, float to surface, wash up on beach
Fatal if not warmed

4. Marine Turtles

5. History Found in fossil record 200 mya (Triassic)
Common in Cretaceous (130 mya)
Present day genera originated 60 (Eocene) and 10 mya (Pleistocene)
Not a very diverse group
Mostly tropical and subtropical

6. Taxonomy Class Reptilia
Order Chelonia- warm to temperate and boreal seas ex. leatherback, ridley's, kemps
Order Chelonia-
F. Cheloniidae- green, flatback, hawksbill,
loggerhead
F. Dermochelidae- leatherback
reduced shell, dermal bone scutes compose
shell
F. Emydidae- diamond back terrapin

7. Anatomy Dorsal shell = carapace Ventral shell = plastron
Head does not retract
carapace
plastron

8. Anatomy
Female
Male

9. Adaptation to salt water
Lacrimal glands-modified tear ducts!

10. Green turtle Scientific Name: Chelonia mydas Diet: seagrass and algae
Size: ~500lbs
Conservation Status: threatened
Habitat: high energy ocean beaches, convergence zones in the pelagic habitat, benthic feeding grounds in relatively protected waters
Range: throughout world in all tropical and subtropical oceans

11. Kemp’s Ridley Scientific Name: Lepidochelys kempii
Diet: mollusks, crustaceans, jellyfish, fish, algae or seaweed, and sea urchins.
Size: 100lbs
Conservation Status: highly endangered
Habitat: shallow water benthic feeder
Range: Gulf of Mexico, Texas

12. Olive Ridley Scientific Name: Lepidochelys olivacea
Diet: jellyfish, tunicates, sea urchins, bryozoans, bivalves, snails, shrimp, crabs, rock lobsters, and sipunculid worms
Size: >100lbs
Conservation Status: highly endangered
Habitat: shallow marine waters
Range: Indo-Pacific, S. Atlantic
NOAA
NOAA

13. Hawksbill Scientific Name: Eretmochelys imbricata Diet: Shellfish
Size: cm ( in)
Conservation Status: Endangered
Habitat: coral reefs, rocky coasts
Range: Tropical Atlantic, Pacific and Indian Oceans; Caribbean

14. Loggerhead Scientific Name: Caretta caretta Diet: Crustaceans
Size: cm ( in), 300 lbs
Conservation Status: Vulnerable
Habitat: coasts, open sea
Range: Temperate and tropical areas of the Pacific, Indian and Atlantic Oceans
NOAA

15. Flatback Scientific Name: Natator depressus
Diet: sea cucumbers, soft corals, jellyfish
Size: < 1 m in length, 200 lbs
Conservation Status: vunerable
Habitat: near continental shelf, shallow, soft bottom sea beds
Range: northern part of Australia

16. Leatherback Leatherback Largest species (7 ft, 1200 lbs)
Family: Dermochelidae: Scientific Name: Dermochelys coriacea
Diet: sea jellies and salps
Size: lbs
Conservation Status: endangered
Habitat: pelagic water
Range: tropical seas, oceanic islands, Atlantic, Pacific, & Indian Ocean
Leatherback
Largest species (7 ft, 1200 lbs)
Global, widest distribution
Dive deep (up to 4000 ft)
“Warm-blooded” (counter-current circulation, fat)

17. Reproduction Mating- at sea
Migration- occurs in late spring; female is accompanied by male
Green sea turtles migrate as far as 800 miles from feeding area to nest in Northwestern Hawaiian Islands
Egg laying behavior- return to same beach (natal beach)

18. Front flippers dig pit, rear flippers carve out burrow
Kemps Ridley nesting
Usually nest at night
Front flippers dig pit, rear flippers carve out burrow

19. Egg tooth- used to chip away at shell
Group effort to get out of nest- emerge at night (safer) and head towards brightest light
Artificial lights- confuse hatchlings
Turtle nest
Cross section

20. Incidental Marine Turtle Catches

21. Marine Debris- plastic bags, soda can plastic rings, fishing line, oil and tar
Costal development and habitat degradation- noise, light, beach obstructions- affect nesting habitat

22. Fibropapilloma- virus in Green turtles
Affects ability to feed, see, move about, or breath
May be due to pollutants, blood parasites, or habitat change
Kaneohe Bay (1991)- >50% infected

23. Clutch size- about 100 eggs & covers pit with sand
Leatherback hatching
Kemps Ridley hatchlings
Clutch size- about 100 eggs & covers pit with sand
Egg incubation- 2 months depending upon species
Sex determined by temperature- males lower temp, females higher temp

24. Predators

25. Factors Affecting Green Sea Turtle Population
Hawaii nesting females
French Frigate Shoals in the Northwest Hawaiian chain
Hunters
Fisheries
Marine Debris
Coastal Development and Habitat Degradation
Fibropapilloma

26. Commercial Value Meat Eggs- nearly forbidden in all countries
with nesting beaches
Soup
Jewelry
Leather
Convention on International Trade in Endangered Species (CITES): turtle commerce prohibited in countries that signed agreement

27. Protection and Management
Law enforcement- in Hawaii, turtles protected under Endangered Species Act
Riding or harassing- $100,000 fine + prison time
Bringing turtle products into Hawaii- $20,000 + prison time

28. Protection and Management
Increase sea turtle populations:
Ranching- eggs or hatchlings from wild populations
Farming- originally from wild populations, for breeding stock

29. Protection and Management
Fishing regulations-
Shrimp Trawlers - incidental catch by commercial shrimp fish nets: drowned 10,000 turtles each year
Drift nets, gill nets
Turtle Excluder Device (TED)

30. Turtle
Excluder
Device

31. How do marine turtles regulate salt in their body?
Inquiry
What is a natal beach?
What advantage is there in turtle hatchlings leaving in a group rather than individually?
Are the consequences for harassing a turtle adequate?
How does the fibropapilloma virus effect green sea turtles?
What is a TED?
How do marine turtles regulate salt in their body?