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Published byMargaret Janis West Modified over 9 years ago
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Marine turtle Marine iguana Saltwater crocodile Marine Reptiles Sea snake
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Sea Snakes
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Diversity: Laticodtidae- krates- 5 species (1 is fw in Solomon Islands) Hyrophidae- 54 different species All derived from Colubrid ancestor; colubrids evolved 40 mya; Laticotids evolved from colubrids 30 mya Location: Laticotids- live from east coast India to Japan and come to the tip of Cape York (Australia) Hydrophiids- found from south tip of Africa to India to South East Asian Islands to Japan to north half of Australia Habitat: Primarily tropical; coastal estuaries, coral reefs, open sea
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Behavior: Often schooling in aggregations Not aggressive but human fatalities have occurred Prey: Feed on small fish or squid, which are killed with powerful venom Predators (few): sharks, snapper, grouper, crabs, saltwater crocodiles, raptors; they descend to escape Osmoregulation: skin is impermeable to salts; salts eliminated by sublingual gland
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Reproduction: Krates are oviparous and lay eggs on land Hydrophiids are viviparous and produce young in the water Not much known about breeding However, olive sea snake breed in spring; seasonal courtship displays
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Largest living crocodilians: 6-7 m long Eggs laid and incubated on land Tropical and subtropical Saltwater crocodiles
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Marine Iguanas Marine lizard endemic to Galapagos islands Herbivorous: graze on seaweeds Salt-glands on nose to eliminate excess salt Recently observed feeding on land for first time They return to land to escape predators.
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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
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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 Class Reptilia Hawaii species- green, hawksbill, leatherback, Olive Ridley
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Class: Reptilia: Reptiles Order: Chelonia: Turtles and Tortoises Family: Chelonidae: Marine Turtles Scientific Name: Natator depressus Diet: sea cucumbers, soft corals, jellyfish Size: < 1 m in length Conservation Status: vunerable Habitat: near continental shelf, shallow, soft bottom sea beds Range: northern part of Australia flatback
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Class: Reptilia: Reptiles Order: Chelonia: Turtles and Tortoises Family: Chelonidae: Marine Turtles 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 Green turtle
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hawksbill Class: Reptilia: Reptiles Order: Chelonia: Turtles and Tortoises Family: Chelonidae: Marine Turtles Scientific Name: Eretmochelys imbricata Diet: Shellfish Size: 76 - 91 cm (30 - 36 in) Conservation Status: Endangered Habitat: coral reefs, rocky coasts Range: Tropical Atlantic, Pacific and Indian Oceans; Caribbean
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Class: Reptilia: Reptiles Order: Chelonia: Turtles and Tortoises Family: Chelonidae: Marine Turtles Scientific Name: Caretta caretta Diet: Crustaceans Size: 76 - 102 cm (30 - 40 in) Conservation Status:Vulnerable Habitat: coasts, open sea Range: Temperate and tropical areas of the Pacific, Indian and Atlantic Oceans Loggerhead
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leatherback Class: Reptilia: Reptiles Order: Chelonia: Turtles and Tortoises Family: Dermochelidae: Marine Turtles Scientific Name: Dermochelys coriacea Diet: sea jellies and salps Size: 1500 lbs Conservation Status: endangered Habitat: pelagic water Range: tropical seas, oceanic islands, Atlantic, Pacific, & Indian Ocean
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reduced shell, dermal bone scutes compose shell 7 dorsal and 5 ventral dermal bones
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Physiology: Poikilothermic (cold blooded) Skin has scales Speed- 35 mph Breath holding- 2 hrs, when sleeping or resting Maturity- 10-50 yrs for green Cannot retract heads like terrestrial turtles Lacrimal gland- salt secretion (drinks seawater)
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Anatomy Has both internal and external skeleton- provided protection and support for organs Fused ribs Powerful sense of smell- find natal beach No ears, but can perceive low frequency sound and vibrations Male & female- difference in tail size; males tail extends past rear flippers, females is shorter
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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)
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Kemps Ridley nesting Usually nest at night Front flippers dig pit, rear flippers carve out burrow
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Turtle nest Cross section 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
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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 Leatherback hatching Kemps Ridley hatchlings
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Sea grass and Algae- adult green sea turtle Epiphytes on sea grass, Sponges, fish, crabs, conch- loggerheads (suction feeders) Gelatinous zooplankton: siphonophores jellyfish Crustaceans, mollusks, echinoderms- Ridley
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Eggs- skunks, raccoons, pigs, lizards, crabs, ants, beetles, fungal and bacterial infections Hatchlings- birds, mammals, crabs Adults- sharks, humans
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Hawaii- 100-350 nesting females French Frigate Shoals in the Northwest Hawaiian chain A.Hunters B.Fisheries C.Marine Debris D.Coastal Development and Habitat Degradation E.Fibropapilloma
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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
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Increase sea turtle populations: Ranching- eggs or hatchlings from wild populations Farming- originally from wild populations, for breeding stock 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 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)
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Catch Statistics (1987) FAO yearbook on Fishery Statistics 3100 metric tons Western Central Atlantic-1200 Eastern Central Pacific- 864 South East Pacific- 305 Western Central Pacific- 258 North West Pacific- 190 Eastern Central Atlantic- 153 Eastern Indian Ocean- 50 Western Indian Ocean- 37 Mediterranean - 20 South East Atlantic- 10
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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
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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
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Turtle Excluder Device
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