MARINE REPTILES [PDF]

MARINE REPTILES

Saltwater crocodile

Marine iguana

Sea snake

Marine turtle

MARINE 

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7000 species Poikilotherm/ectotherm Telur di darat (penyu) 300 jt th lalu Penyu 

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REPTILES

6 species di Indonesia

Ular laut    

55 species 1-1.3 m Ovovivipar Carnivor

Sea Snakes

Yellow- bellied sea snake

Sea Snakes Diversity: • •

Laticodtidae- krates- 5 species (1 is fw in Solomon Islands) Hydrophidae- 54 different species

All derived from Colubrid ancestor; colubrids evolved 40 mya; Laticotids evolved from colubrids 30 mya

Sea Snakes 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; 33-36oC

Sea Snakes

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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 Venom: 2-10 times as toxic as that of a cobras

Sea Snakes

Adaptations to life in the sea 1. Osmoregulation: skin is impermeable to salts; salts eliminated by sublingual gland 2. Developing a flattened paddle-shaped tail and a laterally compressed body. 3. Reduced metabolic rate and increased tolerance for low oxygen levels 4. Lungs- greatly enlarged; hydrostatic organ 5. Gaseous exchange - lungs and the skin.

Sea Snakes 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

Olive Sea Snake

Saltwater crocodiles

• Largest living crocodilians: 6-7 m long • Eggs laid and incubated on land • Tropical and subtropical

Marine Iguanas

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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.

HISTORY •

Found in fossil record 200 mya (Triassic)

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Common in Cretaceous (130 mya)

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Present day genera originated 60 (Eocene) and 10 mya (Pleistocene)

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Not a very diverse group

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Mostly tropical and subtropical

Conservation Status 1. International Union for the Conservation of Nature (IUCN), also called the World Conservation Union 2. The Convention on International Trade in Endangered Species (CITES) 3. The United States Fish and Wildlife Service.

1. Endangered-facing a very high risk of extinction in the wild

2. Vulnerable -facing a high risk of extinction in the wild

3. Threatened-close to qualifying in one of the above categories

MARINE

REPTILES

MARINE 

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Kingdom : Animalia Filum : Chordata Kelas : Sauropsida Ordo : Testudinata Upaordo : Cryptodira Superfamili:Chelonioidea Familia Cheloniidae (Oppel, 1811)     

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Caretta Chelonia Eretmochelys Lepidochelys Natator

Familia Dermochelyidae 

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REPTILES

Dermochelys

Familia Protostegidae (hanya fosil) Familia Toxochelyidae (hanya fosil) Familia Thalassemyidae (hanya fosil)

MARINE      

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TURTLES

penyu hijau (Chelonia mydas) penyu sisik (Eretmochelys imbricata) penyu Kemp’s ridley (Lepidochelys kempi) penyu lekang (Lepidochelys olivacea) penyu belimbing (Dermochelys coriacea) penyu pipih (Natator depressus) penyu tempayan (Caretta caretta)

flatback

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

Green turtle 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

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

Loggerhead 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

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

• reduced shell, • dermal bone scutes compose shell • 7 dorsal and 5 ventral dermal bones

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)

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

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)

Kemps Ridley nesting

Usually nest at night Front flippers dig pit, rear flippers carve out burrow

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

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

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

Eggs- skunks, raccoons, pigs, lizards, crabs, ants, beetles, fungal and bacterial infections Hatchlings- birds, mammals, crabs

Adults- sharks, humans

A. B. C. D. E.

Hunters Fisheries Marine Debris Coastal Development and Habitat Degradation Fibropapilloma

• 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

Catch Statistics (1987) FAO yearbook on Fishery Statistics 3100 metric tons Western Central Atlantic1200 Eastern Central Pacific864 South East Pacific305 Western Central Pacific- 258 North West Pacific190 Eastern Central Atlantic153 Eastern Indian Ocean50 Western Indian Ocean- 37 Mediterranean 20 South East Atlantic10

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

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

Turtle Excluder Device