Manila Bay
Location:	14°25'-14°55'N, 120°32'-121°00'E; intertidal areas from the Municipality of Balanga round the north end of Manila Bay to Cavite City, south of Metro Manila, Luzon.
Area:	c.130,000 ha.
Altitude:	Sea level.
Biogeographical Province:	4.26.12.
Wetland type:	01, 02, 06, 07, 09 & 10.
Description of site:	A large enclosed sea bay fringed by shallow intertidal mudflats and sand flats. The Bay is influenced to the north by the delta of the Pampanga and Meycauayan Rivers. Mangrove is limited and most has been converted to large areas of aquaculture ponds and salt pans. The Bay is saline with fresh water input from numerous rivers, notably the Pampanga River System as well as the Meycauayan and Pasig rivers. There is heavy surface runoff from Mount Bakaan and Mount Natib to the west. Salinities range from about 30 p.p.L in the Bay to almost fresh in the estuaries, depending on rainfall and river discharge. The tidal variation is about l.25m.
Climatic conditions:	Tropical climate with a pronounced dry season from November to April, and a pronounced wet season for the remainder of the year (Type I). The area is protected from the northwest monsoon, but open to the southwest monsoon and cyclonic storms.
Principal vegetation:	Relicts of mangrove swamp, particularly in the Bataan area the dominant species are Rhizophora apiculata, R. mucronata, Avicennia marina, Nypa fruikans and Sonneratia alba. There are also small areas of Schyphiflora hydrophyllacea, S. acida, Acanthus illicifolius and Excoecaria agallocha. Plant communities in adjacent areas include plantations of Cocos nucifera and denuded hill vegetation.
Land tenure:	A mixture of state and private ownership.
Conservation measures taken:	No protected areas have been established. The National Pollution Control Commission and Haribon Foundation have launched an anti-pollution campaign.
Conservation measures proposed:	There may be proposals in existence from Governmeat agencies with regard to pollution, fisheries and aquaculture. Howes (1987) proposed management guidelines for replanting of mangrove species in aquaculture areas, and regular monitoring of shorebird concentrations and the benthic biomass of the intertidal flats.
Land use:	The city and port of Metro Manila, a major centre for international trade and commerce, is situated on the east side of the Bay. Fishing is very important; 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. The milkfish Chanos chanos is the principal species involved. There is a salt pan industry at Cavite in the southeast, and several areas of shanty town development on the shores of the Bay. Surrounding areas are both urban (Metro Manila) and rural (Cocos nucifera plantations and other agricultural activities).
Possible changes in land use:	There is a high likelihood that there will be an increase in aquaculture projects at the expense of the remaining mangrove resources. In 1978 in the Philippines as a whole, there were additional applications for the destruction of about 21% of the remaining mangrove areas for aquaculture projects.
Disturbances and threats:	The many threats to the wetland 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, pollution from heavy industry in the Metro Manila area, and the shooting of shorebirds at fish ponds. There is continued denudation of the natural vegetation in the water catchment area.
Economic and social values:	The site is very important for its fisheries production which supports a large urban population along the periphery of the Bay. It is an ideal area for research on fisheries, wildlife, biomass and marine pollution because of its close proximity to major research agencies.
Fauna:	The intertidal mudflats, fish ponds and salt pans are used by large numbers of migratory shorebirds in winter and during the migration seasons. Monthly counts by S. Gast at a high tide roost on a sandy reclamation area in Metro Manila during the period 1979-1982 revealed a maximum of about 32,000 shorebirds in January 1980. The commonest species were: Pluvialis dominica (8,000) Charadrius dubius (2,000) C. alexandrinus (15,000) C. mongolus (5,000) Calidris ruticollis (2,000)   In early April 1987, J.R. Howes recorded about 8,000 shorebirds of 20 species at sevens sites, mainly drained fish ponds and areas of intertidal mudflat. These included: 2,567 Calidris ruficollis 1,278 C. ferruginea 1,259 Pluvialis dominica 1,374 Tringa stagnatilis Other waterfowl occurring commonly in the Bay include Nycticorax caledonicus, Bubulcus ibis, Egretta garzezla, E. alba, Ardea purpurea, A. cinerea, Sterna hirundo, Chlidonias hybrida (up to 2,000), C. leucoptera (up to 1,000) and Gelochelidon nilotica (up to 2,000). Dolphins have been recorded in the bay.
Special floral values:	The small pockets of mangrove swamp remaining in Pampanga Bay are of considerable value for research and conservation education.
Research and facilities:	A considerable amount of research has been carried out by the National Pollution Control Commission in its Manila Bay Monitoring Project (Phase I). Some studies have been carried out by the Bureau of Fisheries and Aquatic Resources, and shorebird studies have been conducted by the Forest Research Institute and Asian Wetland Bureau. The Forest Research Institute and University of the Philippines at Los Banos are planning to carry out a productivity study of the benthic biomass.
References:	Alas & Tomgson (1987); Alonzo-Pasicolan (1987); Howes (1987); National Water Resources Council (1983a).
Criteria for inclusion:	1b, 1e, 2c, 3a.
Source:	Simplicia Alonzo-Pasicolan, Haribon Foundation and John R. Howes.