Transcript Sea Turtle Biology and Conservation

Sea Turtle Biology and
Conservation
Sea Turtles in Mythology
• Turtles have long been
revered in myths.
• Most Indian tribes see
turtles as being sacred.
• The are seen as being
supernatural because of
their powers for survival.
• The Greeks saw turtles as
standing for wisdom.
More Sea Turtle Myths
• In a Chinese myth, a
turtle was believed to
have developed the
world within its shell.
• Some Indians believe
that the world in
which we live was
formed on the back of
a turtle.
Sea Turtles are still important in
human culture today.
Sea Turtle Identification
1. Kemp's Ridley 2. Hawksbill 3. Loggerhead
4. Green 5. Leatherback
Green Turtle
• Most common species
of sea turtle.
• It’s called the green
turtle because of the
green color of the fat
under shell, they are
not actually green.
Green turtle
• It is one of the largest
species of sea turtles:
3ft long, up to 300 lbs.
• Green turtles can be
recognized because
they have one pair of
scales in front of their
eyes, instead of 2, like
most sea turtles
Black turtle
• Black turtle is named
for the black/gray
color of its shell.
• It is primarily located
in the Eastern Pacific,
and is protected in the
Galapagos and some
areas of Mexico.
Flatback Turtle
• They are named
Flatback because of
their flattened shell.
• Flatback Sea turtles
are only found in
Australia.
Loggerhead Turtle
• Loggerheads can grow
up to 350 lbs, between
31-42 ins.
• They can be identified
by their large head,
reddish brown
carapace (top), and
dull brown plastron
(bottom).
Hawksbill Turtle
• The beautiful shell of
Hawksbill turtles is
often used for jewelry
Olive Ridley
• This is one of the
smallest sea turtles,
weighing only 100lbs.
It is also one of the
most numerous
species of sea turtle.
• It is named Olive
Ridley because of the
olive coloring.
Kemp’s Ridley
• Kemp’s Ridley is the most
endangered species, as
well as the smallest: only
grows to 24-28 ins and 77100lbs.
• They are olive green in
color.
• They only nest on one
beach in the world, in
Rancho Nuevo, Mexico.
Leatherback
• Can dive the deepest
and travel the furthest
of any other turtle.
• They have tough
leathery skin covering
their back.
Leatherbacks
• Largest sea turtle, up
to 7 ft long, 1200lbs.
• Instead of a solid shell
they have bones in
their skin that form 5
ridges.
Navigation
Navigation
• Navigation is finding
the way from one
location to another.
• What are some ways
that people can
navigate?
Navigation
• 1. Compass
• 2. Stars
• 3. Position of Moon and
Sun
• 4. Maps
• 5. Landmarks
• What are some ways that
sea turtles may navigate
in the water and on land?
Navigation
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Sight
Position of the moon
Wave direction
Internal compass
(turtles that we know
use this: loggerhead
and leatherback)
Navigation
• So how do you think
baby turtles navigate
from the nest to the
ocean?
Navigation
• 1. Move away from
silhouettes at the top of
the beach
• 2. Orient themselves
toward the brightest light
(moon on water in low
populated beaches)
• They can sense the
direction of waves when
in the water
• Some use a magnetic
compass.
Navigation
• What are some reasons
a turtle might have to
navigate in the ocean?
• How far do you think
turtles may migrate?
Navigation
•
•
•
•
They migrate to find:
food
mates
and beaches to nest on
Navigation
• Some turtles migrate
over 2600 km but
most will only travel
1000 km.
Reproduction
Reproduction
• Turtles lay eggs in nests
on the beach, usually at
night.
• They can lay up to several
hundred in one nest.
• Many turtles can create
several nests over a few
weeks, during the
reproductive season.
Reproduction
• After laying all their
eggs, the female
turtles return to the
ocean.
• After sixty days the
baby turtles will
emerge and travel to
the ocean, and must
defend themselves.
Conservation
• 1. What is making the
sea turtles endangered?
• 2. How can we protect
turtles and their
habitats?
• 3. Problems being faced
with enforcing laws.
• 4. What can we do?
1. What is making the sea turtle
endangered?
• Coastal development
• A. Destroying nesting
beaches.
• B. Increasing pollution
in bays.
• C. Distracting
hatchlings with light.
• D. Beach vehicle
activity.
1. What is making the sea turtle
endangered?
• Net & Shrimp trawls
• A. Entanglement and
drowning.
• B. Used in trade for
shell and meat.
• C. Destroying feeding
grounds.
1. What is making the sea turtle
endangered?
• Industrial
development
• A. Sand walls
preventing nesting
• B. Oil spills
• C. Damage to coral
reefs and sea grass
beds.
1. What is making the sea turtle
endangered?
• Natural Mortality
• A. Predation as
hatchlings
• B. Predation as
juveniles and adults
• C. Old age
2. How can we protect the turtles
and their habitat?
• Protect nesting grounds
• A. Reserves and wildlife
refuge
• B. Relocate eggs to
hatcheries.
• C. Patrol the beaches
from poachers
• D. Prevent coastal
development and
activity.
2. How can we protect the turtles
and their habitat?
• Education
• A. Get locals involved
• B. Decrease
international trade of
products
• C. Scientific research
• D. Tell others
2. How can we protect the turtles
and their habitat?
• Improvements
• A. Improve fishing
trawls (TED)
• B. Protect with turtle
farms
• C. Decrease pollution
and trash
• D. Get involved
3. Problems being faced with
enforcing laws
• Not all countries have
the money or
manpower to control
poaching on beaches.
• Violations of poaching
may only face a
simple fine, or may be
disregarded.
3. Problems being faced with
enforcing laws
• Jurisdiction varies
between governmental
agencies:
• water = fishery depart.
• land = wildlife and
forest depart.
3. Problems being faced with
enforcing laws
• Turtle farms for trade
and reinstatement cost
millions of dollars and
take 20 to start.
• “to some people . . . trade and
conservation appear to conflict,
but if properly applied, they
could well be the key to
surviving the species”
• --H. Reichart
3. Problems being faced with
enforcing laws
• Local people are not
educated enough in
rural countries and
need turtle meat as a
source of protein.
• Not all nesting
beaches can be
protected.
4. What can we do as students?
• We can do our part in
conservation by simple
acts:
• 1. Picking up trash on the
beach.
• 2. Cutting soda 6-pack rings,
and recycle
• 3. Don’t buy marine animal
products and souvenirs
• 4. Be careful what food we
eat.
4. What can we do as students?
• We can go further by:
• 1. Volunteer in helping
scientists do research.
• 2. Adopt a turtle.
• 3. Become members of
animal conservation
societies.
• 4. Write to your
Congressman.
Interesting Facts:
Archelon is the oldest known fossil at 150MYA.
Found in 1970’s in S.Dakota.
Archelon:
Measured 15ft long (from beak to tail) and 16.5ft wide
(including flippers and shell), weighing @4,500lbs.
Archelon:
Primarily ate giant squid.
Photo Credits
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www.cccturtle.org: #1,7,11,16,17,19,24,29,37,42
www.co.broward.fl.us/bri00600.htm: #5
www.yoto98.noaa.gov/books/seaturtles/seatur1.htm: #6
www.ex.ac.uk/telematics/EuroTurtle/homep.htm:
#8,10,12,14,18,20
www.baja-tortugas.org/conservation.html:
#13,26,32,36,38
www.bonairenet.com/turtle/turtle.htm: #10,15,21,49
www.seaworld.org/Sea_Turtle/seaturtle.html: #23,41,47
www.nps.gov/pais/turtles.htm: #25
Photo Credits cont.
www.turtle.ky: #43, 46
Webhost.bridgeW.edu/EsandG/blkbeach.htm: #45
www.itec.edu.org/conservation.html: #8, 22, 48
J. Ripple. 1996. Sea Turtles. Voyageur Press:
#33, 35, 39, 40, 44
Jeff Seminoff: #9
John R. Hendrickson: #4,27,28, 30, 34
Hometown.aol.com/gonyosoma/folklore.html: #2
www.bonairenet.com/turtle/turtle.htm: #9, 10
www.bhigr.com/pages/info/info-rept.htm: #50,51,52