Transcript Marine Reptiles - Bowie Aquatic Science

Marine Reptiles
Class Reptilia
Characteristics of Reptiles
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Appeared more than 300 million years ago
Evolved to suit life on land
Lungs
Leathery egg shell to prevent drying out
Ectothermic: “cold blooded”
Skin is covered with scales
Sea Snakes Family Hydrophiidae
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Found in Indian and Pacific Oceans
Only 55 living species
Laterally flattened bodies
Flattened tail-like paddle
Ability to close nostrils
Most are 3 to 4 feet long (1-1.3 m)
Most are ovoviviparous: eggs are retained in the
mother and give birth to live young. (A few still
lay eggs on land.)
Sea Snakes cont.
• Carnivores
• Highly poisonous; venom can kill humans
(related to cobra)
• Small mouth and are not aggressive
Marine Iguana
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Only living marine lizard
Found in the Galapagos Islands
Basks on lava rocks to stay warm
Feed on submerged algae
Osmoregulation: excrete salt from a gland
in the nose
Order Crocodylia
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American Alligators are found in freshwater.
Avg 800 lbs and 13 feet
Found from Eastern TX to Florida
Crocodiles are found in freshwater and saltwater
Avg 2,000 lbs and 16 feet
Found Indian Ocean, Australia and W Pacific
Islands
• Can be found in open oceans
Crocodile vs Alligator
Sea Turtles
Characteristics:
• Carapace: armor-like shell that is fused to
their backbone (cannot retract head into
shell)
• paddle-like flippers
• fatty deposits and light spongy bones
increase buoyancy
Nutrition
• Most found in shallow coastal waters where food
is abundant
• Herbivore: Green Sea Turtle- eat turtle grass
• Carnivores: loggerheads- crabs, shellfish,
sponges, fish, horseshoe crabs; hawksbillmussels, clams, jellyfish; Kemp’s Ridley- sea
urchins and other inverts; leatherbacks- jellyfish
in open ocean (pharynx has sharp spines to hold
slippery prey.
Migration
• Travel hundreds of miles away from
feeding ground to its nesting beach where
they were born every 2-4 years.
Reproduction
• Mating takes place in the ocean, males do not
venture onto the shore only females.
• 100-160 eggs are buried in the sand because
a. porous and can dry out
b. protects the eggs from predators
c. keeps the eggs at the right temperature
• eggs hatch after 60 days and hatchlings scurry
to ocean and follow currents and float among
Sargassum (sea weed) only about 10% survive
• Depending on the species; some sexually
mature around age 4 others around age 15
Kemp’s Ridley
Green Sea Turtle
Loggerhead
Leatherback