1. Marine crocs, snakes, lizards, and turtles
Marine Reptiles
Marine crocs, snakes, lizards, and turtles

2. Marine Reptiles 4 groups include: Saltwater crocodile Sea snakes
Marine lizard
Sea turtles

3. Marine reptiles Adaptations of Marine Reptiles Lungs
Amniotic egg – large yolk to nourish developing embryo
Leathery egg case – prevent drying out
Internal fertilization
Most return to land to lay eggs (turtles and crocs)
3 chambered heart (croc has 4 chambered)
Salt glands to get rid of excess salt
Ectotherms (cold blooded) so most live in warm waters

4. Saltwater Crocodiles American Saltwater Crocodile Crocodylus acutus
In US – only located in
Florida
Nonaggressive and shy
Up to 15 feet long
Endangered (500 – 1200 left)
4 chambered heart
Lay eggs in nest and
guard them until hatching
american salt croc.flv

5. Saltwater Crocodiles Australian Saltwater crocodile Crocodylus porosus
Inhabits mangroves and estuaries
Indian ocean and some western pacific islands
Most live on the coast but are known to venture out into the sea
Up to 30 feet long
Very aggressive
Status – of least concern
aussie salt croc.flv

6. Sea Snakes About 50 species (Order Squamata)
All are venomous (although not aggressive)
Related to cobras
Flattened, rudder-like tails
Flaps on nostrils to keep closed
underwater
Salt gland in mouth
One long lung lined with blood
vessels to increase O2 absorption
with simple sac at end to store air
Can hold breath for 2 hours
Most venomous of ALL snakes
sea snake.flv

7. Sea Snakes Bradycardia - decrease in heartbeat in response to diving
(43/min to 7-9/min)
Reproduction - internal fert
Sperm is implanted into oviducts and can be stored for weeks or years until eggs are ripe
Most are ovoviviparous (bear live young)
Some are oviparous (lay eggs)

8. Sea Snakes Olive Sea Snake (Aipysurus laevis) Up to 6 feet long
Fish eater – corners fish in crevices
Indo-pacific including Australia usually near coral reefs

9. Sea Snakes Yellow Bellied sea snake Pelamis platurus
Pacific waters – Cali to Ecuador
Most widely distributed snake
Float at surface like driftwood
to attract small fish – ambush
predator

10. Marine Lizard Only one species – the Marine Iguana
Amblyrhynchus subcristatus
Live in large colonies on the Galapagos islands

11. Marine Lizard Specific adaptations include Flattened tail for swimming
Webbing on all 4 feet
Salt glands above eyes
“sneeze” to expel salt
Powerful claws to
anchor in heavy seas
Regulate buoyancy
by expelling air
iguana.flv

12. Sea Turtles Most widely distributed marine reptile
Sea turtles have been hunted for meat, eggs, shells, leather,
and decorative
objects
They are now
becoming
victims of
pollution and
accidental
bycatch

13. Sea Turtles Characteristics Non retractable heads and limbs
Powerful front flippers to propel and hind fins used for stabilizing and steering
Shells streamlined and flattened
Fatty deposits and light bones increase buoyancy

14. Sea Turtles Feeding Most turtles feed in shallow coastal waters
Vegetarian turtles
Green turtle feeds on meadows of turtle grass throughout the tropics
Black sea turtle feed on algae and sea grasses
Carnivorous turtles
Loggerheads, Hawksbill, Olive Ridley, Leatherback, Kemp’s Ridley, Flatbacks
– feed on crabs, shellfish, urchins, seaweed, sea cucumbers, sponges, fish

15. Sea Turtles Reproduction Born on land but spend their lives at sea
Mature sea turtles return to the beaches on which they were born to lay eggs
Mating occurs in shallow waters

16. Sea Turtles
Female swims to shore at night and drags herself along the beach to find the nesting site
She digs a hole and deposits about 100 eggs
False Crawl – female comes ashore then leaves without laying eggs
sea turtle mom laying eggs.flv

17. Sea Turtles Embryos develop for about 2 months
Eggs at about 30C+ become female, eggs at 28C or lower become male

18. Sea Turtles
Hatchlings breaks through shells and wiggle down to the sea

19. Sea Turtles
sea turtle babies emerging.flv

20. Sea Turtles
8 species – all endangered and protected

21. Atlantic Leatherback (Dermochelys coriacea)

22. Atlantic Leatherback (Dermochelys coriacea)
Largest turtle – up to 6 feet long, 1100 pounds
Rare visitor to Texas Gulf coast
No true shell – leathery, scaleless skin, 7 ridges
Feed mostly on jellyfish

23. Atlantic Leatherback (Dermochelys coriacea)
Primary breeding grounds – Pacific coasts of Mexico and Costa Rica
Reach sexual maturity at 8-15 years
Lay eggs, incubation takes days
Status – endangered
leatherbacks.flv

24. Flatback Turtle (Natator depressus)

25. Flatback Turtle (Natator depressus)
Flat carapace – olive gray color
Up to 3 feet long, almost 200 pounds
Exclusively breeds and nests in Australia
Lays about 50 eggs (the fewest of all turtles)
Incubation 60 days
Sexual Maturity at
7 – 50 years
Feeds mostly on
jellyfish, inverts,
sea cucumbers
Status - vulnerable

26. Hawksbill Turtle (Eretmochelys imbricata)

27. Hawksbill Turtle (Eretmochelys imbricata)
Hawk-like bill – designed for foraging in coral
Scutes on carapace overlap each other
Up to 132 pounds, just over 3 feet long
Feeds on sponges, jellyfish, sea stars, fish, urchins, crustaceans
Eat poisonous sponges
and store toxin in flesh
so this turtle is
poisonous if eaten

28. Hawksbill Turtle (Eretmochelys imbricata)
Lay about 160 eggs, incubate for about 55 days
Reproductive maturity is years
Status –
endangered
hawksbill.flv

29. Olive Ridley (Lepidochelys olivacea)

30. Olive Ridley (Lepidochelys olivacea)
Olive gray above and creamy white below
Up to 100 pounds, about 2.5 feet long
Feed mostly on lobsters, fish, crustaceans, algae, fish eggs, and jellyfish

31. Olive Ridley (Lepidochelys olivacea)
Arribadas – nesting behavior in which breeding turtles congregate and emerge from the sea – en masse!

32. Olive Ridley (Lepidochelys olivacea)
Lay ~100 eggs each, incubate for days
Sexual maturity about 15 years (females at least 2 feet long)
Hatchlings born black – so easy prey against sand
Many predators for hatchlings – 1 survives for every 3000 eggs laid!!  olive ridley.flv

33. Kemps Ridley (Lepidochelys kempii)

34. Kemps Ridley (Lepidochelys kempii)
Smallest sea turtle – up to 2 ft long, 90 pounds
Nest only in the Gulf of Mexico – Rancho Nuevo, Mexico (primary site)
Feeds mostly on crabs, shrimp, and fish

35. Kemps Ridley (Lepidochelys kempii)
Reach sexual maturity at years
Arribada nesting behavior too – like Olive Ridley
Nesting season is April to July
Lay ~100 eggs,
incubate for days

36. Kemps Ridley (Lepidochelys kempii)
Status – most endangered of all turtles
Only 2500 females left today – but just 50 years ago 40,000 females were filmed nesting in just one day on a single beach – so what happened???
kemps ridley arribada.flv

37. Loggerhead (Caretta caretta)
Most common sea turtle found in the U.S.
Up to 4 ft long, 250 pounds
Relatively slow swimmer but can swim fast when threatened (sharks and orcas)
Feeds mostly on crabs, fish, jellyfish, urchins

38. Loggerhead (Caretta caretta)
Reach sexual maturity at years
Lay eggs, incubation is days
Nesting grounds in Florida (about 14,000 each year), and Masirah island, Oman (about 30,000 each year) (Oman is in middle east near Saudi Arabia, Indian ocean)
Status - threatened
sea turtles green vs loggerhead and shark attacks.flv

39. Green Turtle (Chelonia mydas)
Carapace from black to gray to green to brown often with bold streaks or spots
Each has distinctive facial markings – like fingerprints – recognizable by scientists
pounds, 2.6 – 4.3 feet long (largest of hard shells)

40. Green Turtle (Chelonia mydas)
Most widespread species of turtle – found in North America, South America, Africa, Europe, and Asia
Most friendly
is the “honu”
the green
turtles of
Hawaii – swims
with divers
among
coral reefs

41. Green Turtle (Chelonia mydas)
Feeds only on sea grasses and algae as adults
As juveniles – may feed on jellyfish, small mollusks, and sponges
Nest every 2-4 years, sexual maturity is at years!
Lay eggs, incubation is days
Status - endangered

42. Green Turtle (Chelonia mydas)
Exploited for centuries – for example, back in the 1800s, in just one year, 15,000 green turtles were imported to England for meat (green turtle soup), shells, leather
green turtle breathing behavior.flv

43. The Dangers of Being a Sea Turtle...

44. Natural Predation

45. Habitat Destruction

46. Habitat Destruction

47. Light Pollution

48. Net Entanglement and Fishing Line

49. Net Entanglement and Fishing Line

50. POACHING

51. “Accidental” bycatch in shrimp nets

52. “Accidental” bycatch in shrimp nets

53. Marine Scientists in Texas examined 473 turtles stranded along the Texas coast between 1983 and They found ingested plastics in more than half of the turtles sampled.
PLASTIC

54. TEDS.flv
TEDSatTAMUG.flv

56. Sea Turtles Are Protected
REWARD of up to $2,500
For Arrest and Conviction
of Violators
All Sea Turtles Are Protected Under the United States Endangered Species and Lacey Acts. Protection Extends to all Bays, Estuaries, and Open Waters Bordering the United States and Its Territories.