Manila Bay (9710)
Philippines, Asia
Site overview
KBA status: confirmed
Global KBA criteria: D1a
Year of last assessment: 2006
National site name: Manila Bay
Central coordinates: Latitude: 14.7833, Longitude: 120.7667
System: marine, terrestrial
Area of KBA (km2): 955.07884
KBA classification: Global
Legacy site: Yes
Site details
Site description: This IBA includes the extensive intertidal areas from the Municipality of Balanga in Bataan Province round the north and east shores of Manila Bay to Cavite City, south of Metro Manila. This large, enclosed sea bay is fringed by shallow intertidal mudflats and sand flats. Relicts of mangrove swamp survive, particularly in the Bataan area, but most have been converted to large areas of aquaculture ponds and salt pans. Plant communities in adjacent areas include coconut plantations and denuded hill vegetation. The city and port of Metro Manila is situated on the eastern side of the Bay. The site is very important for its fisheries production that supports a large urban population along the periphery of the Bay. There are high concentrations of fish traps and extensive mariculture within the open sea area, and aquaculture schemes cover about 70 km of the coastline. There is a salt pan industry at Cavite in the southeast, and several areas of shantytown development on the shores of the Bay.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs. KBA identified in the CI/CEPF Conservation Outcomes booklet for the Philippines Hotspot (2006). Taxonomy, nomenclature and threat category follow the 2004 IUCN Red List.
Additional biodiversity: Large numbers of migratory shorebirds uses the intertidal mudflats, fishponds and salt pans in Manila Bay in winter and during the migration seasons. Monthly counts at a high tide roost in Metro Manila in 1979-1982 revealed a maximum of about 32,000 shorebirds in January 1980, and in early April 1987, about 8,000 shorebirds of 20 species were recorded at seven sites, mainly drained fish ponds and areas of intertidal mudflat. It has consistently registered the highest numbers of waterbirds at any site in the Philippines during the Asian Wetland Counts in 1990-1994. There have been records of several threatened waterbirds there, but it is unclear whether this IBA is of significance for the conservation of any of these species.
Habitats
Summary of habitats in KBA: This IBA includes the extensive intertidal areas from the Municipality of Balanga in Bataan Province round the north and east shores of Manila Bay to Cavite City, south of Metro Manila. This large, enclosed sea bay is fringed by shallow intertidal mudflats and sand flats. Relicts of mangrove swamp survive, particularly in the Bataan area, but most have been converted to large areas of aquaculture ponds and salt pans. Plant communities in adjacent areas include coconut plantations and denuded hill vegetation. The city and port of Metro Manila is situated on the eastern side of the Bay. The site is very important for its fisheries production that supports a large urban population along the periphery of the Bay. There are high concentrations of fish traps and extensive mariculture within the open sea area, and aquaculture schemes cover about 70 km of the coastline. There is a salt pan industry at Cavite in the southeast, and several areas of shantytown development on the shores of the Bay.
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Marine Neritic | 14 | |
| Marine Coastal/Supratidal | 14 | |
| Artificial - Aquatic | 29 | |
| Artificial - Terrestrial | 14 | |
| Marine Intertidal | 29 |
Threats
Summary of threats to biodiversity at KBA: The many threats to Manila Bay include the destruction of the remaining patches of mangroves for aquaculture, reclamation of intertidal areas for housing development, road construction and salt pans, continuous dredging and pollution (solid waste, domestic sewerage, industrial waste, and oil spills). There is continued denudation of the natural vegetation in the water catchment area. The heavily polluted and silted Pasig River drains into the bay. Shooting of shorebirds at fishponds and dynamite fishing are additional threats to the bay’s biodiversity. Construction along the shoreline, especially in the Roxas Boulevard area, has disturbed the roosting areas of shorebirds, which have been forced to use alternative roosting places, such as the NAIA Complex.
Additional information
References: References: Custodio (1996); Davies et al. (1990); Scott (1989).