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yewitnesses
say that 30 years ago it was common to see hundreds of fresh turtle tracks
each night on most of the beaches of the Turtle
Islands. Indeed, historical records show that the Turtle Islands were
famous at least until the middle of this century for the tremendous numbers
of green turtles that nested there. In the early 1950s, Jose Domantay
of the Bureau of Fisheries reported that there were relatively few turtles
nesting on the islands of Great
Bakkungan and Lihiman.
At Taganak, however,
he found that nesting occurred year round, with as many as 60 or more
nestings a night especially in the months of July and August. He calculated
that about 3,000 turtles nested every month on the islands.
Sadly, it has become
rare in recent years to observe more than 30 turtles nesting in a single
night on any of the islands, except at Baguan Island Marine Turtle Sanctuary
(BIMTS), where about 100 clutches of eggs can be laid in a single night
during the peak in the nesting season: from July to September. Since 1951,
egg production on Taganak
has declined by approximately 80% (Table 1).
Table 1. Egg production
(number of eggs reported collected) on Taganak Island, Turtle Islands,
Tawi-Tawi, Philippines, for the period August 8-September 11 during different
years. Data from 1951 are from Domantay (1953) and those from the years
1984-1993 are from De Veyra (1994). For comparative reasons, data are
presented for the specified 35-day period because the data for 1951 are
available for this period only.
|
Year
|
EGG
PRODUCTION
(number of eggs reported collected)
|
%
REDUCTION from the 1951 value
|
|
1951
|
137,254
|
|
|
1984
|
22,135
|
83.87
|
|
1985
|
16,530
|
87.96
|
|
1986
|
30,133
|
78.04
|
|
1987
|
24,209
|
81.77
|
|
1988
|
41,596
|
69.69
|
|
1989
|
27,526
|
79.94
|
|
1990
|
15,515
|
88.70
|
|
1991
|
36,334
|
73.53
|
|
1992
|
18,401
|
86.59
|
|
1993
|
21,647
|
84.23
|
Green turtles need
decades to reach sexual maturity. During this long period, they face many
threats, both on beaches and in the ocean. There are many hazards that
occur naturally, but the rapid decline of the turtle population in the
Sulu Sea can be largely attributed to harmful human activities in the
area. The turtles have survived countless natural threats and natural
catastrophes through millions of years, but now people are pushing them
closer than ever to the brink of extinction. Needless to say, only people
can restore them to their old glory.
While in the ocean,
adult green turtles have to avoid large predators such as sharks and killer
whales. And even when they survive these predators and arrive after a
long migration at the Turtle Islands to breed and nest, these adult turtles
face still more threats. They may be caught by trawlers or long-lines,
or destroyed by dynamite, before they even reach the beaches to lay eggs.
The lights on the shore may scare them away and keep them from climbing
up the beach. On the beach, huge logs may block their way, preventing
them from finding a suitable place to dig a nest. Also, on some beaches
covered with litter, they may not find room to nest.
The
beaches on the Turtle Islands are often littered with huge logs, tree
trunks and other debris. Sometimes the turtles can get over these obstacles
but many times they are prevented by logs from reaching their nesting
site. (PCP, file)
Even if the turtles
have successfully laid their eggs, this does not guarantee that the baby
turtles will survive, grow up to reproduce, and thus maintain the population.
In many cases, the eggs are harvested by egg collectors soon after they
are laid.

A female green turtle that has finished nesting, leaving
her eggs on the beach to incubate for about two months. (Stuewe,
Oct. 1998)
Though powerful, fast and graceful at sea, turtles are awkward
and slow on land. In many places, people take advantage of this and catch
and slaughter nesting turtles on the beach. In this respect, the green
turtles that nest in the Turtle Islands are lucky - generally, Turtle
Islands residents do not kill turtles. But there have been reports of
people slaughtering gravid ("pregnant") turtles at sea to take their eggs.
It takes about two
months for sea turtle eggs to hatch, and during that time the eggs are
left unattended, as mother sea turtles do not protect their nests. So
even if the eggs are not collected by people, their survival is still
not assured because they face other threats. Monitor lizards, ghost crabs
and even rats and ants can dig into the nests and devour the eggs. Once
they hatch, the baby turtles, called hatchlings, must dig themselves out
of the nest and make their way to the sea. While crawling on the beach
toward the sea, they can be eaten by the same animals that dig into the
nests, as well as by birds, dogs and cats. Inland lights disorient them,
so they don't make it to the sea. Offshore, bright fishing lights attract
them, drawing them to where there are concentrations of predatory fishes
and fishing activities. Even just getting off the beach, across the reefs
and out to sea can be a major ordeal for the hatchlings, because predatory
fishes wait for them to cross the reef during their first swim.
Many of these typical
turtle hazards are described in an illustrated comic book on turtle conservation
produced by the World
Wildlife Fund - Philippines. Copies are available upon request at
kkp@wwf-phil.org.ph
 
The sea turtle conservation booklet, showing the turtle hazards puzzle
on the back cover (left) and the front cover (right). (WWF-Philippines)
Trawlers
Many shrimp trawlers operate around the Turtle Islands. These boats drag
large nets along the bottom, catching whatever gets in their way. Sometimes,
sea turtles are trapped in the nets. Since turtles are air-breathing reptiles,
they drown if they are dragged within the nets for several hours. They
thus become part of the incidental catch (called by-catch) of the trawlers.
Incidental catch is not well documented in the Turtle Islands, but former
crew members report that as many as three turtles can be caught in a trawler's
nets during a single night. What is more, the trawlers are not from the
Turtle Islands, and most of them are not even from the Philippines.
Shrimp
trawlers sometimes trap and drag sea turtles in their nets for several
hours. The turtles drown and are usually thrown overboard as part of the
trawlers' incidental catch. (PCP, file)

Many dead and decomposing male and female turtles are washed ashore each
year on all the Turtle Islands, and there may be countless more out in
the open sea that are never seen. (PCP, file)
The closer the trawlers
are to the coastline, the greater is the chance that they will catch turtles.
Most of the nesting green turtles spend months in the vicinity of the
Turtle Islands, waiting for yet another clutch of their eggs to mature.
Tracking studies indicate they stay within 40 km of the shore for at least
a few months. Waiting to reproduce, these turtles are likely victims of
trawling operations.
The
Philippine Fisheries Code of 1998 prohibits the use within municipal
waters of active fishing gears, including trawls (the gear of choice of
many operators of commercial fishing boats). Municipal waters extend up
to 15 km from the coastline, but the municipality can issue an ordinance
allowing commercial fishing boats to operate within 10.1-15 km from the
shoreline in municipal waters more than 7 fathoms deep.

Patrol boat of the Philippine Navy (left) anchored off Taganak
harbor. (Stuewe, Oct. 1998)
Actually, trawling
does not have to be so devastating on turtles. Fisheries specialists have
developed Trawling
Efficiency Devices (also called Turtle Excluder Devices or TEDs).
TEDs are installed in trawl nets, just before the "bag" or "cod
end", and will deflect most turtles out before they get caught.
.
Diagram of an otter trawl equipped with a TED
Long-line
Fishing
There is a good market for shark fins in Sabah, and throughout much of
Asia, so good that many fishermen at the Turtle Islands set "long-lines"
for sharks. The hundreds of baited hooks on a single line may attract
hungry turtles to the "easy bait". If a turtle is hooked and unable to
come up to the surface to breathe, it will drown. Countless thousands
of sharks are caught in long-lines each year just for their fins. The
sharks are thrown back into the sea after the fins are cut off and they
die from maiming and the removal of their means of swimming. Many
species of sharks, dangerous or harmless, are now endangered.

A shark fisherman attaches bait to the dozens of
hooks on his long-line in preparation for setting the line at sea. (Stuewe,
Oct. 1998)

Shark fins being dried in the sun at Taganak, Turtle
Islands. In most cases, the fin is all of the shark that is kept - the
shark is thrown back into the sea, alive but severely wounded, to slowly
bleed to death. (Stuewe, Oct. 1998)
Purse Seining and Night Fishing
The Philippine Fisheries
Code of 1998 prohibits the use within municipal waters of "superlights"
(bright lights employed by commercial fishing vessels to attract fish),
because these lights give commercial fishers such high catch efficiency
as to present unfair competition to fishers operating less efficient gear.
Despite the ban, however, superlights are often used in municipal waters.
What is more, these
lights brighten the horizon at night near many beaches in the Philippines,
including the Turtle Islands, and for this reason, superlights
have adverse effects on turtle populations. They may disturb the nesting
process of the adult female turtles. Hatchlings are even more negatively
affected, because they are attracted to the superlights, which draw them
off course from their normal dispersal into the open ocean. Some hatchlings,
if they are lucky, may just waste precious time and energy, but many meet
concentrations of predatory fish, which are also attracted to the lights,
or get caught up in fishing operations.
Beach Development
Population pressures also pose a threat to the turtles. These arise not
only from the high human birth rate in the region, but also from an influx
of human settlers to the Turtle Islands. Every year, problems of peace and
order in Mindanao are driving more and more migrants in search of
safer homes to the Turtle Islands. One fisherman who recently arrived on Boan
said his fishing boat was stolen three times in the last few months, so
he finally decided to pack up and come to the Turtle Islands, a relatively
safer place. Many of the residents build their houses on the shores of
the islands and keep their boats on the beach, thus reducing the area
of sandy, undisturbed beach available for turtles to dig their nests.
Also, the growing number of settlements is using more lights, which distract
the nesting turtles and disorient the hatchlings.
The islanders themselves
are now experiencing problems associated with population growth, such
as reduced availability of safe drinking water and arable land to grow
subsistence crops.

Beach development, such as this settlement on Taganak,
Turtle Islands, poses a threat to sea turtles, typically by reducing the
area of sandy, undisturbed beach available for the turtles to nest. (Stuewe,
Oct. 98)
Egg collection
Collection and trade of turtle eggs is a tradition throughout the region.
While egg collection is strictly prohibited at the Baguan Island Marine
Turtle Sanctuary, 60% of the egg production in the five other Philippine
Turtle Islands is legally harvested for local trade and consumption (Ministry
of Natural Resources Administrative Order No. 33, Series of 1982).
Egg traders, however, prefer to bring the eggs to Sandakan, Sabah, the
most accessible market near the Turtle Islands. This is in violation of
the Convention on International Trade in Endangered Species of Wild Flora
and Fauna (CITES), of which both Malaysia and the Philippines are Parties.
The Joint Management Committee of the two-nation Turtle
Islands Heritage Protected Area (TIHPA) is currently evaluating efforts
to study the turtle egg trade to be able to implement a scheme that would
reduce pressure on the turtle population.
Direct exploitation
of turtles
The turtles have also been exploited for their meat. Domantay (1953) reported
that, during the Japanese Occupation, a large number of turtles that nested
on the Turtle Islands were killed to feed troops. Evidently, tens of thousands
were slaughtered, with estimates ranging from 3,000 to 150,000.
These days, very few
sea turtles are intentionally slaughtered on the islands, but the other
threats that the turtles are facing will have to be countered if the population
is to be restored to its former level. The drastic reduction in egg production
that the PCP found several years ago is certain to be a result of the
many threats that the turtles faced over the years, as well as the long-term
effects of the rampant slaughtering of nesting females in the past and
the very heavy exploitation of eggs that still occurs on the islands.
A single female green
turtle can potentially lay thousands of eggs during her lifetime, so the
loss of reproducing turtles is especially important for the future of
the population. The full impact of such loss may not be seen for years,
however. Turtles are an important component of our marine ecosystems and
have great economic value. In the end, we may never know the price that
we are paying for past indiscriminate exploitation.
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