Geographic Location: They are found throughout the Pacific, Atlantic, and Indian Oceans. In the Pacific, their range extends as far north as Alaska and south beyond the southernmost tip of New Zealand. In the Atlantic, they can be found as far north as Norway and the Arctic Circle and south to the tip of Africa. They are mainly pelagic (open ocean) wanderers but migrate to tropical and subtropical coastal regions to mate and nest.( Osborne,2015) In 1982, scientists estimated that there were 115,000 adult female leatherback sea turtles worldwide. Recent estimates have placed the number between 20,000 and 30,000 (Singh,2007). Trends in Population: The global population for this species was estimated to be 115,000 adult females in 1982. By 1996 this had been revised down to about 30-40,000. Leatherback populations in the Pacific and Indian Oceans have undergone dramatic declines in the past forty years. For example, the nesting colony at Terengganu, Malaysia went from more than 3,000 females in 1968, to 20 in 1993, to just 2 in 1993 - there are no signs of recovery.  Similar scenarios have occurred in Indonesia, Sri Lanka, Thailand, and Mexico. Numbers of females recorded at four formerly major Pacific rookeries have declined to about 250 in Mexico, 117 in Costa Rica, two in Malaysia, and fewer than 550 in Indonesia(Anonymous, 2006) Reproduction: Leatherbacks mate offshore in shallow waters near the nesting area. The females dig their flask-shaped nests at night on sloping sandy beaches backed by vegetation. Six clutches can be laid in a season, with a 10-day period between nesting. The females may renest up to 7 miles from the first nest. An average clutch contains 80 to 85 eggs and incubation takes from 55 to 74 days. The 3-inch hatchlings emerge at night and head toward the ocean. The turtles reach sexual maturity at 6 to 10 years of age; the females nest every second or third year.  In the U.S., nesting occurs from about March to July.  Female leatherbacks nest an average of 5 to 7 times within a nesting season, with an observed maximum of 11 nests.  Most leatherbacks remigrate to their nesting beaches at 2 to 3-year intervals.  (Department of energy and environmental protection, 2014) Threats: 1- Marine pollution It is the greatest threat for leatherback sea turtles, while they accidentally eat balloons and plastic bags floating in the water which they mistaken as jellyfish. (Leigh,2015) 2- Overharvesting and illegal: Egg collection on many turtle nesting beaches is a very serious threat, especially in Southeast Asia where a culture of legal egg collection leads to the removal of tens of thousands of eggs. This practice has contributed to the local extinction of leatherbacks in Malaysia.  Within the last several decades extensive egg collection and the killing of adult turtles in Indonesia has resulted in huge population declines throughout the region. Despite protective legislation, many eggs produced each year in Central America are.

1. Geographic Location:
They are found throughout the Pacific, Atlantic, and Indian
Oceans. In the Pacific, their range extends as far north as
Alaska and south beyond the southernmost tip of New Zealand.
In the Atlantic, they can be found as far north as Norway and
the Arctic Circle and south to the tip of Africa. They are mainly
pelagic (open ocean) wanderers but migrate to tropical and
subtropical coastal regions to mate and nest.(
Osborne,2015)
In 1982, scientists estimated that there were 115,000 adult
female leatherback sea turtles worldwide. Recent estimates have
placed the number between 20,000 and 30,000 (Singh,2007).
Trends in Population:
The global population for this species was estimated to be
115,000 adult females in 1982. By 1996 this had been revised
down to about 30-40,000. Leatherback populations in the
Pacific and Indian Oceans have undergone dramatic declines in
the past forty years. For example, the nesting colony at
Terengganu, Malaysia went from more than 3,000 females in
1968, to 20 in 1993, to just 2 in 1993 - there are no signs of
recovery.
Similar scenarios have occurred in Indonesia, Sri Lanka,
Thailand, and Mexico. Numbers of females recorded at four
formerly major Pacific rookeries have declined to about 250 in
Mexico, 117 in Costa Rica, two in Malaysia, and fewer than 550
in Indonesia(Anonymous, 2006)
Reproduction:
Leatherbacks mate offshore in shallow waters near the nesting
area. The females dig their flask-shaped nests at night on
sloping sandy beaches backed by vegetation. Six clutches can be
laid in a season, with a 10-day period between nesting. The
females may renest up to 7 miles from the first nest. An average

2. clutch contains 80 to 85 eggs and incubation takes from 55 to
74 days. The 3-inch hatchlings emerge at night and head toward
the ocean. The turtles reach sexual maturity at 6 to 10 years of
age; the females nest every second or third year.
In the U.S., nesting occurs from about March to July. Female
leatherbacks nest an average of 5 to 7 times within a nesting
season, with an observed maximum of 11 nests. Most
leatherbacks remigrate to their nesting beaches at 2 to 3-year
intervals. (Department of energy and environmental protection,
2014)
Threats:
1-
Marine pollution
It is the greatest threat for leatherback sea turtles, while they
accidentally eat balloons and plastic bags floating in the water
which they mistaken as jellyfish.
(Leigh,2015)
2-
Overharvesting and illegal:
Egg collection on many turtle nesting beaches is a very serious
threat, especially in Southeast Asia where a culture of legal egg
collection leads to the removal of tens of thousands of eggs.
This practice has contributed to the local extinction of
leatherbacks in Malaysia. Within the last several decades
extensive egg collection and the killing of adult turtles in
Indonesia has resulted in huge population declines throughout
the region. Despite protective legislation, many eggs produced
each year in Central America are still collected for subsistence
or commercial use. Hunting and egg collection persists
throughout the Indian Ocean as well.
(Leigh,2015)
3-
Hapitat loss:

3. Sea turtles are dependent on beaches for nesting. Sea level rise,
uncontrolled coastal development, vehicle traffic on beaches,
and other human activities have directly destroyed or disturbed
sea turtle nesting beaches around the world. Turtle feeding
grounds such as coral reefs and sea grass beds are also damaged
and destroyed by activities onshore, such as sedimentation from
clearing of land and nutrient run-off from agriculture.
(Leigh,2015)
4-
Fisheries by catch
:
Worldwide, hundreds of thousands of sea turtles a year are
accidentally caught in shrimp trawl nets, on longline hooks and
in fishing gillnets. Sea turtles need to reach the surface to
breathe, and therefore many drown once caught. (Leigh,2015)
Action:
The World Wide Fund for Nature (WWF) is trying to save
leatherback turtles from extinction by doing several things.
First,
WWF works to reduce turtle bycatch by helping the fisheries to
switch to more turtle-friendly fishing hooks and advocate the
use of devices that exclude turtles from nets. WWF runs an
international competition to solve bycatch problems. Winning
devices was designed to minimize the bycatch of turtles on tuna
longlines and help turtles avoid gillnets. Also,WWF works with
fishermen to help them save turtles caught in fishing gear and
they use satellite devices to track turtle movements to help
prevent future interactions between fisheries and turtles.
Second
,
WWF establishes marine protected areas (MPA) all over the
world to make sure marine turtles have a safe place to nest,
feed and migrate freely. For example,In the Bird's Head

4. Seascape of the Coral Triangle, WWF works to protect the
nesting area of the largest remaining population of leatherback
turtles in the Pacific Ocean. WWF also supports the patrolling
of leatherback turtle nest beaches helps equip local turtle
conservationists (Leigh,2015)