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Sea Turtles Animal Study & Lapbook
created by Tina Franks
Lapbook Templates
Vocabulary Words
Pick and choose a few new words to learn as you encounter them in your
reading.
Beak—the hard upper part of a turtle’s mouth, which it uses for eating
Carapace—the top part of the sea turtle’s shell (the part on its back)
Carnivore—meat eater, eats other animals
Clutch—a group of sea turtles egg
Coded Wire tag—a piece of computer-coded metal wire that can hold a magnetic charge; is injected into a turtle’s flipper by syringe
Cold-blooded—animal that can’t make its own heat; its blood is the same temperature as the water or air it lives in
Currents—steady flow of ocean water caused by the magnetic pull of the earth
Driftnet—a large fishing net that stretches large distances
Endangered—not many left in the world; in danger of dying out completely and becoming extinct
External—outside the body
Extinct—gone completely; no more left of a species
Feeding grounds—an area where an animal goes to find food
Flippers—flat “arms” shaped for swimming
Flipper tag—a metal tag on a sea turtle’s flipper (kind of like an earring) that is marked with an individual ID number; not permanent
Hatch—to break out of an egg
Hatchling—a baby sea turtle that has just hatched from its egg
Herbivore—plant eater
Internal—inside the body
Life cycle—a set of changes that all animals go through
Life span—the length of time an animal lives
Living tag—a permanent mark created by putting a small piece of the plastron onto the carapace that will grow with the turtle
Longline fishing—a type of fishing that uses a very long line with a great number of hooks
Magnetic pull—the force that causes a magnet to point either to the North Pole or to the South Pole
Migrate—travel back and forth between feeding grounds and nesting grounds; moving from place to place
Omnivore—eats both animals and plants
PIT
tag—a microchip with an individual ID number that is injected into the turtle;
same as the microchips that are put into your pets
Plankton—tiny sea animals that serve as food for baby sea turtles
Plastron—the bottom part of the sea turtle’s shell (the part on its belly)
Predator—an animal that hunts other animals for food
Reef—coral, rocks and sand that make up a hard ridge in the water
Reptile—cold-blooded, scaly-skinned animal
Satellite—an object in orbit around the earth that can receive from and send information back to the earth
Scutes—the scales (or divisions) on a turtle’s shell and/or head
Seagrass—a grassy underwater plant
Species—a group of animals that have the same characteristics and can mate with each other
Stranding—when a turtle washes up on a beach and is not a hatchling or a mother nesting
Threatened—the species is declining, not growing; this is what comes before “endangered”
Transmitter—a device that sends out signals
Trawl net—a fishing net that is shaped like a funnel and dragged behind a boat
Turtle Excluder Device—a sort of escape hatch in a trawl net that allows a sea turtle to escape from the net if it accidentally gets caught
General Sea Turtle
Facts
You can’t really
tell how old a turtle is just by looking at it. If the turtle was tagged with a
living tag, you’d know for sure. But scientists have discovered that you can
also discover a turtle’s age from its bones. Just like tree trunks, you
can determine a turtle’s age by looking at the number of rings on its bones.
(Unfortunately, this is something that can only be determined on dead sea
turtles.)
A turtle is a reptile, so it is cold-blooded. It’s body is only as warm or as cold as the water around it.
Turtles are the only reptiles that have a shell.
A turtle is an air-breathing reptile, so it has to swim to the surface for air to breathe.
Even though they spend most of their lives under water, they do need to come up for air every 5 to 10 minutes. (See the next fact for an exception to this.)
Sea turtles split their time between eating and resting. Some find a patch of coral reef or a beach to rest on. Others dive to the bottom of the sea to rest. They store oxygen in their blood and muscles, so if they’re not moving around much, they can stay underwater for several hours before they have to come up for air. They also swim great distances to get from their feeding grounds to their nesting grounds.
Sea turtles are found in warm oceans throughout the world.
As they get bigger and swim around more and more, algae starts to cover the turtles’ shells. This algae slows them down in the water and can make them sick. To get clean, sea turtles go somewhere little fish, and sometimes shrimp, gather (a turtle “cleaning station”) and let them nibble the plants that grow on their shells. This can take anywhere from a few minutes to a few hours. The turtles get cleaned off and the little fish and shrimp get a good meal. (There’s a very neat photo of this on page 11 of the book Sea Turtles by Don Patton.)
Protection from Predators
One way that turtles are protected from predators is by their coloring.
Think about a turtle in the water. Imagine that you are a bird flying above the
water. If you look down into the water, you’ll have a hard time seeing the sea
turtles against the deep, dark ocean water. Their carapaces (top shells) are
dark colored and blend in well with the dark water. Now imagine that you’re
a shark, deep in the ocean. Look up. You’ll have a difficult time
seeing the sea turtles from beneath them because their light-colored plastrons
(bottom shells / bellies) blend in with the bright sky above. The way a sea
turtle is colored, with a dark carapace and a light plastron is called
countershading. Dolphins are also protected by countershading.
The Reptile Family
There are four main groups of reptiles. They are:
1. Alligators and crocodiles
2. Tortoises, turtles and sea turtles
3. Tuataras
4. Lizards and snakes
Here is a chart of the differences between sea turtles and other turtles.
|
Sea Turtles |
Other Turtles |
|
|
|
|
Only 7 kinds |
About 240 different kinds |
|
Flippers (which help them swim, steer and glide) and no claws |
Webbed feet (which help them walk on land) and claws |
|
Have good hearing |
Most don’t hear well |
|
Can’t pull its head and flippers into its shell |
Able to pull inside its shell |
|
Excellent swimmers |
Only some are good swimmers |
|
Migrate far (thousands of miles, in some cases) |
Don’t migrate |
|
Lives in the sea, except when nesting (and that’s only females) |
Lives on land and in fresh water (lakes, rivers, streams, ponds) |
Sea Turtle Anatomy
Flippers—A sea turtle’s front flippers make it a strong swimmer, able to swim as fast as 20 miles per hour. That’s 4 times faster than we can swim. A sea turtle’s back flippers are for turning and stopping. Because their flippers are made to help them swim well, they are not so good for traveling on land. Its swimming motion looks more like a bird flapping its wings than swimming.Sea turtles aren’t able to pull their flippers and heads into their shells like other turtles.
Shell—The top of a turtle’s shell (the turtle’s back) is called the carapace. It is covered by large scales called scutes. The bottom (the turtle’s belly) is called the plastron. They’re connected by bony bridges all around. Soft, flexible skin allows the turtle to move its head and flippers.
Senses—Sea turtles have very good senses of smell and hearing. They can also see well far away underwater, though their eyesight is poor on land.
Ears—Sea turtles don’t have actual ears, like many other animals. Instead they have special hearing organs in their heads just behind their eyes.
Eyes—Sea turtles’ eyes are protected by thick eyelids.
When you see a sea turtle out of the
water if often looks as if they’re crying. Actually, that’s their body’s way
of getting rid of some of the sea salt that they soak up while they’re in the
water.
Nose—They breath air through two nostrils, just like we do.
Mouths & Teeth—Sea turtles DO NOT have teeth. They have saw-like ridges on their jaws that are useful for tearing sea grass and other aquatic plants. What isn’t torn up by their powerful jaws gets swallowed whole.
Did You Know? - Male sea turtles have longer tails than females.
Sea Turtle Reproduction Facts
Every 2-4 years, in late spring or summer, sea turtles migrate great distances
to return to the exact same beach where they were born. They don’t get lost,
either! Why is that? No one really knows for sure, but some scientists think
that the turtles might be able to find the right beach using the moon and the
stars to guide them. Others think that they might feel the magnetic pull of the
earth or remember certain familiar smells that are carried along by the
currents.
A mother sea turtle can lay up to 500 eggs in a season—between 80 and 120 eggs at a time, every 2 weeks. (Why so many? Because very few sea turtles make it to adulthood.) Most sea turtles will nest about 4 to 6 times in one year but then might skip a few years before they nest again.
The nesting process (digging the deep hole in the sand, laying the eggs, covering them back up with sand and hiding the nest) takes anywhere from 1 hour (for loggerheads) to many hours (green sea turtles dig much deeper nests than the other species).
Sea turtle eggs look a lot like ping pong balls and are soft and leathery. A group of eggs is called a clutch. A cool nest means more males while a warm nest means more females.
The sand protects the eggs from many things: the sun and the heat, predators who would eat them (raccoons, coyotes, foxes, wild dogs, ants and people have all been known to dig up nests for the eggs), heavy rains and large waves (which could flood the nest).
The eggs hatch about 2 months after the mother laid and buried them. Hatchlings use a sharp egg tooth to break out of their shells.
Hatchlings, which are no bigger than a bar of soap, have to dig up through the sand to get to the surface. It takes them anywhere from 3 days to a full week to dig out of their nest and they have to work as a team to do it. From there, they have to crawl to the ocean (which is very dangerous because of predators) and swim out to sea.
Baby sea turtles find the sea by following the light of the moon sparkling on the water. How does that work? The sky looks brighter over water than it does over land. They get confused, though, if there are other bright lights (street lights, signs, houses, etc) near a beach.
Once at sea, the hatchlings migrate to where adult sea turtles live, where they are prey to whales, sharks and fish (which is another reason so few of them survive long enough to become adults). Out in the open sea, the babies float amongst seaweed which hides them from predators. Baby sea turtles eat mainly floating seaweed and algae and plankton (floating sea creatures).
When the babies are about 10” (the size of a dinner plate), they swim back in to shallower waters where they can get bigger food, which is usually found on the ocean floor. Leatherbacks, however, stay out at sea and eat jellyfish.
Sea Turtles Are Endangered
Sea turtles are endangered animals. All species of sea turtles are listed as
threatened or endangered.
Sea turtles have been hunted by both man and animal for their meat and their shells. Their eggs have been dug up, again by both man and animal, for food.
Nesting beaches have been taken over by the human population. Bright lights and excess noise cause hatchlings to get lost and go the wrong way and get killed on roads or get eaten by predators. Trash, such as balloons and plastic bags, are mistaken for tasty jelly fish and can quickly kill a turtle if eaten.
Trawl nets (large nets, dragged along through the water by shrimp boats) sometimes snag turtles and they drown because they can’t get free and swim to the surface for air. Hooks from longline fishing lines get stuck in their mouths or throats when they eat the bait off of the lines and kill them. Driftnets are another danger to the sea turtle, as are boat propellers.
It’s been estimated that, over the last twenty years, the world’s sea turtle population has dropped by half.
What is the Endangered Species Act? The Endangered Species Act of 1973 was designed to protect plant and animal species, and the ecosystems they depend on, that had been put in danger of extinction due to economic growth and development. The list of species is divided into two main categories: endangered and threatened, with “endangered” being much closer to extinction than the “threatened” species. As of April 2007, there were a little over 1300 species on the threatened and endangered lists. To download the entire Endangered Species Act of 1973 or to search for a specific species or browse the entire list, go to http://www.fws.gov/endangered.
The 7 Species of Sea Turtles
There are seven species of sea turtle. Scientists can tell the species apart by the number and pattern of scutes (plates) on the turtle’s shell.
Kemp’s ridley
Ridleys are the only sea turtles that nest during the day. Kemp’s
ridleys live ONLY in the eastern Atlantic Ocean. These sea turtles have
heart-shaped / round gray-green (more gray than green) shells. Baby ridleys
are black, not gray-green. They grow to be about 2 or 2 1/2 feet long and
can weigh up to 100 pounds. The Kemp’s ridley is the smallest of the sea
turtles AND the most endangered. Ridleys are carnivores and like to eat
fish, crabs and snails.
Olive ridley
Ridleys are the only sea turtles that nest during the day. Olive
ridleys live in both the Pacific and Atlantic Oceans, as well as the Indian
Ocean and the Caribbean Sea. These sea turtles have heart-shaped
green-gray (more green than gray) shells. They grow to be about 2 1/2 to 3
feet long and can weigh up to 100 pounds.
Ridleys are carnivores and
like to eat fish, crabs and snails.
Hawksbill
Hawksbill sea turtles live in the Atlantic, Pacific and Indian Oceans.
They have an oval shell that are a pretty brown-gold color with streaks of
white, green, red and black. They grow to be about 3 feet long and can
weigh up to about 200 pounds. These turtles get their name because their
mouths look like a hawk’s bill. This turtle is a carnivore… It eats mainly
sea sponges, even poisonous and spiky ones, sea urchins and jellyfish.
Flatback
Flatback sea turtles have a gray-green oval shell and can grow to be about 3
feet long and about 200 pounds. Like their name, a flatback’s shell is
flatter than the shells of other species of sea turtles. Flatbacks live
ONLY in the shallow waters near the northern and northeastern coasts of
Australia.The flatback sea turtle is a carnivore and prefers to eat shellfish
and sea cucumbers.
Loggerhead
These turtles grow slowly. A female loggerhead isn’t able to lay eggs until
she’s between fifteen and thirty years old. Loggerheads may swim nearly
forty miles a day searching for food. The loggerhead sea turtle is the
most common sea turtle found in the southeastern United States. It has a
wide square-shaped head and very powerful jaws. Loggerheads have a
reddish-brown oval shell and can grow up to about 3 to 4 feet long and up to
about 400 pounds. They live in the Atlantic, Pacific and Indian Oceans and
the Mediterranean and Caribbean Seas. This turtle is an omnivore. It
will eat algae, jellyfish, crabs and small shellfish and sponges. This turtle
can often be found poking around coral reefs, rocky areas and sunken ships
looking for food.
Green sea turtles
The green sea turtle is the only sea turtle that’s a vegetarian. Green
sea turtles have a brown or black oval-shaped shell and can grow to be about 3
1/2 to 4 1/2 feet long and weigh between 350 to 500 pounds. This species
of turtle is named for the color of its body fat, which is green. Green
sea turtles live in the Atlantic, Pacific and Indian Oceans and the
Mediterranean and Caribbean Seas. (There is a subspecies, sometimes called
the 8th species of sea turtle, known as the black sea turtle or the East Pacific
green sea turtle. For our purposes, they are grouped with the green sea
turtles.) This turtle is a herbivore; it is the only sea turtle that is a
herbivore. Very rarely it will eat sponges or jellyfish, but usually it eats
seagrass and seaweed. A green sea turtle can stay under water for up to 5
hours.
Leatherback
Leatherbacks have interlocking pieces of bone (sort of like a jigsaw puzzle)
directly underneath their leathery backs. This is the largest, in
size, of the species of sea turtles. A leatherback can grow to be up to 8 feet
long and weigh up to 1500 pounds. The leatherback does not have a hard
shell, but instead a thick, soft, rubbery one. Its shell is brown to black and
teardrop-shaped with 7 bony ridges running the length of its shell.
Leatherback turtles love in the Atlantic, Pacific and Indian Oceans but they
also do alright in colder waters and have been found in Canadian waters.
The leatherback sea turtle is also the deepest diver of the seven species, able
to dive down about 1300 feet. This turtle is a carnivore and eats mainly
jellyfish, especially the poisonous Portuguese man-of-war. An interesting fact
is this: a leatherback can eat its own weight in jellyfish every day!
Leatherbacks are the biggest reptile alive today
Recommended Resources
Sea Turtle Activity and Coloring Book
Sea Turtle Identification Key (with species descriptions)
Non-Fiction Reading Recommendations
Turtle Watch by George Ancona
I’m a Sea Turtle by Darlene R. Stille
Sea Turtles by Gail Gibbons
Sea Turtles by Don Patton
The Life Cycle of a Sea Turtle by Bobbie Kalman
Watch Me Grow: Turtle by Lisa Magloff
Sea Turtles by Frank Staub
Sea Turtles by Elizabeth Laskey
Turtle Tide: The Ways of Sea Turtles by Stephen R. Swinburne
One Tiny Turtle by Nicola Davies
Turtle Rescue: Changing
the Future for Endangered Wildlife
by Pamela Hickman
Fiction Reading Recommendations
The Lighthouse Family - The Turtle by Cynthia Rylant
Into the Sea by Brenda Z. Guiberson
Turtle Bay by Saviour Pirotta
Turtle in the Sea by Jim Arnosky
Web Links for Further Research
http://nationalzoo.si.edu/ConservationAndScience/AquaticEcosystems/SeaTurtles/ - good information on sea turtles from the Smithsonian National Zoological Park
http://www.marinebio.com/ - you can search for any marine species and get loads of information from this site
http://world-turtle-trust.org/turtletales.html - legends and stories about sea turtles from around the world
http://www.onr.navy.mil/focus/ocean/life/turtle1.htm - several pages on the green sea turtle
http://www.oceanconservancy.org/site/PageServer?pagename=SEE_turtles_resources - links to information and resources (including a very cool coloring/activity book); this organization seeks to connect tourists to sea turtles to promote and support ongoing efforts to protect sea turtles
http://www.cccturtle.org/sea-turtle-information.php - website for the Caribbean Conservation Corporation and Sea Turtle Survival League - this link takes you to a page entitled “Information on Sea Turtles and Threats to Their Survival” - very good information and photos here
http://www.pbs.org/odyssey/odyssey/20021216_log_transcript.html - “A Night With a Nesting Sea Turtle” from PBS’s “The Voyage of the Odyssey”
http://www.pbs.org/odyssey/odyssey/20050223_log_transcript.html - “Loggerheads” from PBS’s “The Voyage of the Odyssey”
http://www.pbs.org/wnet/nature/turtles/navigate.html - “Voyage of the Lonely Turtle” from PBS; has an exceptionally good photo section on the anatomy of a sea turtle
http://galveston.ssp.nmfs.gov/seaturtles/tours/index.html - National Marine Fisheries Service Sea Turtle Facility at the NOAA/NMFS Galveston Laboratory; click on the sea turtles link on the left side for slide show presentations , or click on the kid stuff link on the left side for their sea turtle activity/coloring book
http://www.nationalgeographic.com/ngkids/9911/turtle/ - National Geographic Kids—Turtles in Trouble
http://www.seaworld.org/infobooks/SeaTurtle/home.html - information on sea turtles from Sea World
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