The Puerto Princesa Subterranean River National Park in Palawan
Province features spectacular limestone karst landscape country and an
underground river which is accessible by boat for tourism. Puerto
Princesa National Park is best described by the UNESCO submissions for
its listing as a World Heritage Site, which say, '' One of the
distinguishing features is that it emerges directly into the sea with
its lower portion thereby subject to tidal influences. The area has
significant habitat for biodiversity conservation and contains the full
‘’mountain to sea ‘’ ecosystem with some of the most important forests
in Asia.
The focus of the area is a spectacular Karst landscape
containing an 8.2km long subterranean river, one of the most unique of
its type in the world. The underground river includes many
speleotherms, and several large chambers exist, up to 120 meters in
width and 60 meters in height. The limestone mountain has extensive
karst features, both surface Karst (pinnacles, shafts, dolines and
limestone cliffs), as well as an extensive underground river system.
A
distinguishing feature of the river is the fact that it emerges
directly into the sea, and that the lower portion of the river is
brackish and subject to tidal influences. The underground river, the
Cabayugan River, arises approximately 2km southwest of Mount Saint Paul
at an altitude of 100m, and flows underground for almost its entire
length to an outflow into St. Paul’s Bay.
All rivers and associated
tributaries are within the SPSRNP nomination, which is important in
relation to catchment impacts on the water quality of the Cabayugan
River. Three forest formations are present: lowland, karst and
limestone. Approximately two-thirds of the nomination is forested,
dominated by hardwood species. The karst forest is restricted to small
pockets where soils have developed. In the coastal area, mangroves,
mossy forest, sea grass beds and coral reefs are also found.
The
significance of forest biodiversity within the nomination is discussed
in Section 3 of this report. The Alugan Bay component of the SPSRNP has
been noted by a number of reviewers as having national significance for
its mangrove forest. The faunal diversity in the SPSRNP is moderate,
especially with respect to invertebrates. Endemic mammals include the
Palawan tree shrew, Palawan porcupine and Palawan stink badger.
Dugong
have been recorded in the marine component of the park. Monitor lizard
and marine turtles are also present. The Palawan Peacock Pheasant has
also been recorded in the SPSRNP ( recognised as an internationally
threatened species ). The subterranean fauna has not been studied in
detail, but comprises fish, prawns, snakes and insects. The tunnel and
chambers of the subterranean river are home to abundant populations of
swiftlets and bats.
Eight species of bats are also found in the cave,
and cave swiftlets nest on some of the underground boulder piles.
Further studies are required to determine the extent and diversity of
the underground fauna.
St. Paul Underground River has similar
geomorphological qualities as some other limestone areas in South and
Southeast Asia, notably Gunung Mulu National Park in Sarawak, Phong Nha
Nature Reserve and Ha Long Bay in Vietnam, Lorentz National Park in
Irian Jaya and Gomantong in East Malaysia. The vast majority of
existing World Heritage karst sites are in temperate regions. Within
the tropical karst region the following comparisons can be made. Ha
Long Bay in northern Vietnam contains significant karst topography and
caves, in a spectacular coastal setting. This site was not nominated on
the basis of these values but the potential World Heritage significance
of karst values within the site has recently been reviewed. The caves
in Ha Long Bay are mostly small in comparison to the St. Paul
Subterranean River, but they do have ancillary value as they provide
key evidence of changing sea levels on the Sunda Shelf. In Thailand,
the Thungyai Huai Kha Khaeng Wildlife Sanctuaries contains significant
areas of lowland riverine forest and other forest types more typical of
strongly seasonal tropical climates. This property includes low-relief
limestone terrain with some caves, and karst wetlands. The major
feature of the nominated area is the 8km underground river. There are
many underground rivers in other karst regions around the world. For
example, the Clearwater Cave and the 37km Melinan River in Sarawak’s
Gunung Mulu National Park have arguably more significant underground
rivers. Within the Philippines a 9km river cave exists at Callao on
Luzon. The underground river in St. Paul is not as dramatic as similar
features found in existing World Heritage sites in Slovenia’s
Skocjanske Jama, Kentucky’s Mammoth Cave or the Canadian Rockies
Castleguard and Maligne River Caves.
One feature that
distinguishes St. Paul, however, is that the underground river flows
directly into the sea amidst a tropical coastal setting. The
underground river flowing into the sea, and the associated tidal
influence, makes this an outstanding feature. One reviewer also noted
that St. Paul warrants special consideration simply because it is one
of the few such rivers which the general public can easily experience
and appreciate.
There is one other World Heritage site in the
Palawan Biogeographic Province, the Tubbataha Reef Marine Park.
However, this protects different values from those identified for St.
Paul. Palawan is an important biogeographic province, with a rich biota
drawn from both Malaysian and Pacific sources. Palawan is distinct from
the rest of the Philippine archipelago as it lies on the Sunda Shelf
and has derived most of its fauna from Borneo during recent geological
times.
The biodiversity within this site is considered
significant. The Palawan Moist Forest, which is represented within the
nomination, is noted in WWF’s Global 200 report as having the richest
tree flora of Asia, with high levels of regional and local endemism.
The Palawan Moist Forest also has the largest and richest examples of
limestone forests in Asia. The St. Paul National Park is also noted, in
a recent global overview of forested protected areas on the World
Heritage List, as a forested protected area which may merit
consideration for World Heritage nomination.
The conservation
significance of this forest at the In conclusion, SPSRNP has a number
of features that combine to distinguish it from other areas.
These include:
[ 1 ] The underground river flowing directly into the sea amidst a tropical forest setting, with its associated tidal influence;
[
2 ] The forests within the nomination which are amongst the most
significant in Asia, being representative of Palawan Moist Forest, and
which have been identified in a number of expert reviews as having
World Heritage potential; and
[ 3 ] The fact that this is the most
important site for conservation in the Palawan Biogeographic Province.
The coverage of a complete “ mountains to the sea ecosystem ”, within
the nomination international level is heightened when considered in the
context of the high levels of past and current deforestation in the
Philippines and in the region. For example, the Environmental Legal
Assistance Centre of Puerto Princesa notes that: “ in 1903, there were
more than 21 million hectares of forest in the Philippines, or more
than half of the country’s total area. Today, less than 6 million
hectares of forest are left. In 1994, there were only 800,000 hectares
of old growth forest left ”. Palawan has, in fact, been described as “
the last best hope ” for forest conservation in the Philippines.
St.
Paul Cave was known to local people since ancient times, in their
thoughts it was inhabited by a spirit that prevented them from entering
the cave. The park’s territory and surroundings are theancestral lands
of the Batak and Tagbanua communities. The needs of the local
communities are being considered through the preparation of the
previously mentioned management guidelines.
Ulugan Bay
This
area is located within the nominated area, and it comprises mangrove
forests in various conservation states. It has been estimated that 15%
of the mangroves in the Philippines are in Ulugan Bay. Possible threats
to Ulugan Bay from a proposal to establish a Naval base are a worry. ''
