GEOGRAPHIC LOCATION

Sarangani Bay is located at coordinates 6 degrees 07’ N latitude and 125 degrees 06’ E longitude. It is bounded by some of the coastal towns of Sarangani Province, namely: Maasim on the west, Alabel on the north, and, Malapatan and Glan on the east. General Santos City which is a chartered city of South Cotabato Province also borders the Bay on the north. The Bay is under the legal jurisdiction of both Sarangani Province and General Santos City.

PHYSICAL FEATURES

Sarangani Bay encloses an area of 449.22 sq.km from Tampuan Pt. in Maasim to Sumbang Pt. in Glan and opens into the Mindanao and Celebes Sea. Portions of the municipalities of Glan, Maitum, and Kiamba not enclosed within the bay but part of the Celebes Sea are referred to as "adjoining waters" of the bay. The coastline length of the bay from Glan extending to Maasim is about 79 km with an average depth of 350 m. The waters in Sarangani Bay are strongly oceanic in salinity. Tide-generated currents are generally weak, except near the mouth of the bay.

The reefs around the bay are narrow and support only small patches of seagrasses. Mangrove areas along the bay have been converted to fish and prawn ponds and utilized for firewood, especially along the coastal communities of General Santos City, Alabel and Malapatan.

REEF STRUCTURES AND CORALS

In the study conducted by Dames and Moore (for Louis Berger International Inc. (LBII)), a total of 42 coral genera were identified from the various survey sites established in the different municipalities of Sarangani Province and General Santos City. Dominant genera include Acropora, Porites, Diploastrea, Goniopora, Montipora and Favites.

The condition of coral reefs surveyed varies, from exceptionally good to heavily degraded. Maasim, Glan, Alabel and Malapatan have sites with live hard coral cover exceeding 50%. In terms of dead coral cover, ten sites exceeded 10% and seven of these are in Glan. Ten sites showed high rubble cover; five in Glan, four in Maasim and one in General Santos City (Table 1). The reefs on the northern part of the bay were exposed to sedimentation causing the loss of diversity and degradation of the reefs. Only soft coral patches are found sparsely distributed in the area.

NOTEWORTHY FAUNA AND FLORA

A total of 230 coral reef fish species belonging to 33 families have been recorded from the different sites. The most numerous fishes in order of the number of species are: damselfishes (Pomacentridae), wrasses (Labridae), groupers (Serranidae), surgeonfishes (Acanthuridae) and butterflyfishes (Chaetodontidae). The target fishes in decreasing order of standing stock are: surgeonfishes, fusiliers, parrotfishes, goatfishes, snappers, emperor breams and jacks. Most fishes were small (<15 cm), with only few commercially important species. On the whole, large predators were very few in the site, implicating the exploited condition of these sites and an inability to support large fish biomass.

The steepness of the subtidal area in most of the coastline prevents the establishment of any seagrass meadows. The dominant species in Maasim is Enhalus while Halophila and Thalassia are dominant in other areas.

Squids are caught in large volumes in the bay. Rare endangered marine mammals (e.g., dugongs and whales) have been sighted in Sarangani Bay.

SCIENTIFIC IMPORTANCE AND RESEARCH

In depth study of the coral reefs and related resources has yet to be conducted. Assessment of coral reef was first conducted by Dames and Moore for LBII as part of the US-AID funded coastal management plan of SOCSARGEN last 1993. The Marine Biology Department of the MSU-College of Fisheries has an on-going study of specific coral reef sites in the bay. The bay is also a station for the landed catch and effort monitoring (LCEM) of the DA-BFAR/FSP Tuna Research Project from 1993 to 1995 conducted jointly by BFAR, PRIMEX and SPC.

ECONOMIC VALUE AND SOCIAL BENEFITS

Fishing on the coral reefs of Sarangani Bay is commonly practiced by the municipal fishermen from different areas. Tourism in the coastal area is not yet developed but there are already eight existing beach resorts that cater to the residents and local visitors. Glan and Kiamba have white sandy beaches with reef diving attractions ideal for the promotion of tourism.

Sarangani Bay is the richest tuna fishing ground in the country. Results of the fish monitoring conducted by Mindanao State University-General Santos Foundation (MSU-GSF) revealed that 168 species are caught within the bay itself, 97% of the catch comprised of pelagic species. In 1995 for example, total catch for October and November was valued at PhP 4.8 M (MSU-GSF). There are approximately 49 corporations into fishing, 5,400 commercial fishers and 32,000 municipal fishermen (LBII 1993). Fishes landed in the bay are small (e.g., frigate mackerels, roundscads) and large pelagics (tunas, mackerels, marlins and flying fishes), and demersal fishes (snappers, breams, groupers and moonfishes). Throughout the year, the most abundant catch are the tunas, scads and flying fishes.

DISTURBANCES AND BENEFITS

Throughout the coastal area, there was evidence of destruction of corals due to rampant practice of dynamite fishing. Furthermore, heavy sedimentation is evident at the mouths of rivers particularly those entering the north of the bay. Silway, Buayan and Malabulan rivers have major impacts on the fringing reefs. Formerly extensive fringing reefs in the mouth of the bay have been heavily silted and now contain a very low diversity of corals (LBII, 1993). Seagrass areas on the north and east of the bay are subject to periodic and heavy sedimentation from the major rivers. Although, the bay is ideal for ports because of the general lack of typhoon, the absence of wind prevents vertical mixing and dilution making entrainment of pollutants and sediments along the coast more likely.

Fishing intensity in coral reefs and coastal areas is extremely high and fishermen who resorted to destructive methods, such as, blast fishing have left large areas of reef physically destroyed as a viable habitat for fish.

LEGAL PROTECTION

Sarangani Bay was declared as a Protected Seascape under the NIPAS act (RA 7586) giving management authority to DENR. An existing Memorandum of Agreement empowers local government agencies and other departments (e.g., DENR) to manage the area, as well.

RECOMMENDATIONS

Reefs retaining high percentage of coral cover should be protected while degraded reefs should be rehabilitated to maintain or improve the condition of the habitat. Laws against blast fishing and other destructive methods should be strictly implemented coupled with environmental information and education campaign.

(Editor’s Note: Considerable amendments were provided by Mr. Ramon Miclat and Ms. Hilly Ann Roa-Quiaoit.)

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