Conservation and Ecology of Marine Reptiles MARE 490 Dr. Turner Summer 2012 - PowerPoint PPT Presentation

slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Conservation and Ecology of Marine Reptiles MARE 490 Dr. Turner Summer 2012 PowerPoint Presentation
Download Presentation
Conservation and Ecology of Marine Reptiles MARE 490 Dr. Turner Summer 2012

play fullscreen
1 / 69
Conservation and Ecology of Marine Reptiles MARE 490 Dr. Turner Summer 2012
188 Views
Download Presentation
caraf
Download Presentation

Conservation and Ecology of Marine Reptiles MARE 490 Dr. Turner Summer 2012

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Conservation and Ecology of Marine Reptiles MARE 490 Dr. Turner Summer 2012

  2. Reptilian Origins Mammalia Aves Reptilia

  3. Class Reptilia Order Chelonia – marine turtles Order Squamata – marine snakes and iguanas Order Crocodilia – saltwater crocodile

  4. Class Reptilia 6,000 living species of reptiles (lizards, snakes, turtles, crocodiles) Dry skin covered with scales (prevent H20 loss) Air breathing Marine taxa include sea turtles, sea snakes, marine iguana, and saltwater crocodile

  5. Marine Turtles Marine turtles tied to terrestrial environment for oviposition - process of laying eggs Other Aquatic Reptiles: iguanas, crocodilians, ichthyosaurs - tail undulation for locomotion

  6. Marine Turtles Marine turtles: lost capacity of tail undulation Developed shortened, rigid body form & corselet (breastplate) Limbs required profound modification from terrestrial existence

  7. Limb Modification Forelimbs modified into paddles: - elongate phalanges enmeshed in a continuous matrix of tough connective tissue Foreclaws reduced to three on each limb

  8. Order Chelonii 2 Families: Cheloniidae & Dermochelyidae 7 or 8 species found throughout 3 tropical Oceans 3 species have restricted distribution: Flatback – northern Australia Kemp’s ridley – Gulf of Mexico, N. Atlantic Black sea turtle – eastern Pacific

  9. Order Chelonii Turtles & tortoises – monophyletic group or clade “Pseudoturtle” Placochelys

  10. Order Chelonii Cretaceous – 4 families: Toxichelyidae Protostegidae Cheloniidae Dermochelyidae

  11. Order Chelonii - Extinct - Extant

  12. Family Toxichelyidae Small/medium sized, broad-shelled marine turtles - diverged from Cheloniidae

  13. Family Protostegidae A group of large to gigantic turtles - Rhinochelys sp. Parallels with dermochelyidae

  14. Family Protostegidae

  15. Order Chelonii - Extinct - Extant

  16. Family Cheloniidae Shell covered in horny scutes Variable in number Typically 5 pairs on carapace; 6 of plastron

  17. Family Dermochelyidae Reduction in bones of the carapace & plastron No scutes

  18. Cheloniid Diversity At one point – 31 genera 5 extant: Chelonia sp. Eretmochelys sp. Lepidochelys sp. Caretta sp. Natator sp.

  19. Genus Chelonia Description: 4 pairs of lateral, non-overlapping scutes 2 extant species: Chelonia mydas Chelonia agassizii

  20. Genus Chelonia Chelonia mydas:4-pairs lateral scutes, 1 pair prefrontal scales, non-overlapping scutes, round head, serrated jaw; to 230kg, shell 125cm

  21. Family Cheloniidae Chelonia mydas – green sea turtle Herbivore Fibrilopapilloma – 49-92% Nest French Frigate Shoals ≈1,000 females

  22. Family Cheloniidae Chelonia mydas – green sea turtle

  23. Major Nesting Areas C. mydas

  24. Genus Chelonia Chelonia agassizii: 4-pairs lateral scutes, 1 pair prefrontal scales, non-overlapping scutes, round head, serrated jaw; to 230kg, shell 125cm Black pigmentation Restricted to E. Pacific

  25. Family Cheloniidae Chelonia agassizii – black sea turtle 4 pairs of non-overlapping lateral scutes Pacific coast of S. America

  26. Family Cheloniidae Chelonia agassizii – black sea turtle

  27. Major Nesting Areas C. agassizii

  28. Genus Eretmochelys Description: 4 pairs of lateral, overlapping scutes 1 extant species: Eretmocheyls imbricata

  29. Genus Eretmochelys Eretmocheyls imbricata: 4-pairs lateral scutes, 2 pairs prefrontal scales, overlapping scutes, pointed head, overbite; to 85kg, shell 95cm

  30. Family Cheloniidae Eretmocheyls imbricata – Hawksbill sea turtle 4 pairs of overlapping lateral scutes Shell highly prized; $100/lb Until 1992 – 20 net tons/Japan Nests on beaches of Hawaii

  31. Family Cheloniidae Eretmocheyls imbricata – Hawksbill sea turtle

  32. Major Nesting Areas E. imbricata

  33. Genus Lepidochelys Description: 5-6+ lateral scutes, round carapace 2 extant species: Lepidocheyls olivacea Lepidocheyls kempi Olive Kemp’s

  34. Genus Lepidochelys Lepidocheyls olivacea: 6+-pairs lateral scutes, carapace nearly circular, 4 bridge scutes with pores, juvenile-charcoal, adult-olive green; to 45kg, shell 70cm Restricted to tropical waters

  35. Family Cheloniidae Lepidocheyls olivacea – Olive ridley sea turtle 6+ pairs of non-overlapping lateral scutes Widely Distributed Doing fairly well Rarely found around Hawai′i

  36. Family Cheloniidae Lepidocheyls olivacea – Olive ridley sea turtle

  37. Major Nesting Areas L. olivacea

  38. 5-6 Genus Lepidochelys Lepidocheyls kempi: 5-6 pairs lateral scutes, carapace very round, 4 bridge scutes with pores, juvenile-charcoal, adult-grey-green; to 45kg, shell 70cm Restricted to Gulf of Mexico & S. Atlantic

  39. Family Cheloniidae Lepidocheyls kempi – Kemp’s ridley sea turtle 5 pairs of non-overlapping lateral scutes Most critically Endangered 1947-42,000 ♀; 1980’s -1,000♀ Shrimp trawl bycatch

  40. Family Cheloniidae Lepidocheyls kempi – Kemp’s ridley sea turtle

  41. Major Nesting Areas L. kempi

  42. Genus Caretta Description: 5-6 lateral scutes, carapace longer than wide 1 extant species: Caretta caretta Loggerhead Kemp’s

  43. Genus Caretta Caretta caretta: 5-6 pairs lateral scutes, carapace longer than wide, 3 bridge scutes with no pores, broad head, red to red-brown; to 200kg, shell 120cm

  44. Family Cheloniidae Caretta caretta – Loggerhead sea turtle 5 pairs of non-overlapping lateral scutes Nests in S. Japan – only in N. Pacific; prevalent in Gulf of Mexico and Atlantic

  45. Family Cheloniidae Caretta caretta – Loggerhead sea turtle

  46. Major Nesting Areas C. caretta

  47. Genus Natator Description: 4 pairs of lateral, non-overlapping scutes; 1 extant species: Natator depressus

  48. Genus Natator Natator depressus: 4-pairs lateral scutes, 1 pair prefrontal scales, non-overlapping scutes, round head, serrated jaw; to 90kg, shell 100cm Dorso-ventrally flattened