The species richness of marine biodiversity of the Spratlys in the West Philippine Sea (South China Sea) is high. Countries surrounding this group of islands, including the Philippines, Vietnam and China, should realize the importance of this fact, and should agree to conserve the biodiversity resources for the benefit of their peoples. Any activity that harms this rich biodiversity will be counterproductive to their interests and the welfare of the world and the future generations.
Our present knowledge of the biology and oceanography of the Spratlys is based on the earlier researches of the Vietnamese and Chinese scientists who dealt primarily with the dynamics of ocean waters.
The recently concluded Philippines-Vietnam Joint Oceanographic & Marine Scientific Research Expedition in the South China Sea (JOMSRE-SCS) in 1996-2007 added more information (see Alcala-edited Proceedings of JOMSRE [2008] and Aliño et al. [1998] on the Kalayaan Group of Islands).
The JOMSRE studies deal with marine biology as well as physical, chemical and geological oceanography, although the recent geological studies have not as yet been published.
The JOMSRE expeditions studied coral reefs associated with submerged shoals and atolls and the intervening deep-water parts of the South China Sea.
The sites surveyed were Scarborough Shoal, Trident Shoal, Nares Bank, Menzies Reef, North Danger Reef, and Jackson Atoll from 1996 to 2007, a time period of 11 years.
The platform used for the 2005-2007 expeditions was the Philippine NAMRIA vessel, BRP Hydrographer Presbitero.
I will deal mainly with the biological resources, which I hope are sufficiently of interest to our people and the government of the Philippines.
The Spratlys present a unique marine environment because it consists of submerged coral reefs (shoals), atolls sometimes with emergent islets but always with lagoons, and deep parts of the ocean that connect the scattered coral reefs via ocean currents.
These currents carry propagules from one reef site to another. The lagoons hold the nutrients needed for biological production and serve as habitats of marine species.
An estimated 214 species of corals exist in the Spratlys. This number is about 40 percent of the species reported in the southern Philippines, which 533.
One thing noticed in these lagoons is the lack of large vertebrates like mammals and turtles, and there is evidence that these have been overexploited. The turtle skulls on beaches remind us that they were present there before.
The fish species on the coral reefs of the Spratlys have been estimated to number some 400 species in 45 Families, including the common seven Families of reef fish containing the target (food) species. The densities of fish go as high as 3,000 individuals/500 square meters.
However, there was noted a lower biomass of harvestable fish at 39 tons/square kilometer in 1997 as against 114 tons/square kilometer in 1997, showing depletion during the intervening 10-11 years.
Other marine species like sea cucumbers and giant clams have also been found to exist in reduced numbers. In fact, sea cucumbers were found being dried by fishers in Jackson Atoll in 2007.
The presence of a high biodiversity in the Spratlys is of great importance because their propagules are expected to be carried by ocean currents to the countries surrounding the West Philippine Sea.
Hence, the need for marine protected areas in the Spratlys.