Philippines the actual work of maintaining protected areas. Activities include patrols, habitat restoration, maintenance and interpretation for visitors (PAWB, 1991). PAWB has a number of major programme areas, but one of the most important is the establishment and management of protected areas. Activities include identification of new sites, boundary marking and periodic assessment, as well as restoration of degraded sites, management of buffer zones and visitor facilities. Protected areas administration has historically been weak, due to the many institutional reorganisations as well as institutional and juridical struggles. This was particularly true during the period when the Parks and Wildlife Office was subsumed into the Bureau of Forest Development (Nrmc1983)furtherstaffingfunding, training and administrative support have been inadequate (Fernandez, 1988; Penafiel, 1990). In common with terrestrial areas, marine protected areas also suffer from a confused legislative and administrative background and there is no national governmental mechanism to manage marine areas. In 1977 the Marine Parkreserve Development Inter-agency Task Force was set up by Special Order No. 61 to formulate an integrated system of plans and programmes for marine conservation. Under the Presidential Proclamation No. 1801 of 1978 the Philippine Tourism Authority (PTA) assumed responsibility for the promotion and development of aquatic sports. This has led to the establishment of several marine reserves and tourist zones. The Coral Reef Research Team, within the Bureau of Fisheries and Aquatic Resources (Ministry of Natural Resources), is responsible for marine conservation within marine reserves. The non-governmental organisation movement in the Philippines has been gaining considerable momentum over the last few years. Since the overthrow of the Marcos government, both NGOS and the media have become more vocal against issues of pollution, forest degradation and destructive practices in the marine environment There are now some 11 conservation and environmental NGOS and 17 university or academic-related organization in the country. The Haribon Foundation has taken on a leading role for the environmental NGO network and an environmentally sympathetic constituency is forming among the public and in the new senate and congress (Petocz, 1988). The Haribon Foundation has also been directly involved in the development of protected areas (Balete, 1990). University research centres and institutes, such as the Marine Science Institute at University of Philippines, Diliman, the Institute of Terrestrial Ecology and Marine Research Institute at Silliman University, the Institute of Environmental Science and Management at University of Philippines, Los Banos and Ecosystems Research and Development Bureau of the Department of Environment and Natural Resources stationed at University of Philippines, Los Banos have all contributed significantly to developing conservation activities in the country. Systems Reviews Tropical forests originally covered ahnost 280,000 sq. km (93) of the total land area of the Philippines, and still two-thirds of it at the end of World War II (Cox, 1988). There are many published estimates of the current extent of forests, but these are based on different definitions of forest cover and on various information sources covering different periods of time. Consequently, an overall synthesis of the situation is difficult. An estimated 30% (90,000 sq. km) still supports productive or regenerating forest (Cox, 1989). Figures published by Revilla (1986) indicate, however, that forest with at least 40% crown cover may cover only 22% of total land area. The most valuable forests, both economically and biotically, are old-growth dipterocarp formations which cover 9,840 sq. km (33) (Penafiel, 1991). Multispectraspot satellite imagery from 1987-1988 clearly shows the fragmentary nature of the remaining cover, as forests are divided into increasingly isolated vegetation islands (Collins et al, 1991). Furthermore, forest cover is largely restricted to higher land, as human activities preferentially clear lowland vegetation. Major forest blocks, therefore, are restricted to the Sierra Madre and Cordillera Central in Luzon, Central Samar, the highlands around Mt Ragang and other areas to the east in Mindanao. The only extensively forested island is Palawan, principally due to low human population density. However, projected deforestation trends suggest that all but an irreducible minimum of approximately 1 000 sq. km of montane and low quality scrub forest will remain in Palawan by 2010 (HTS, 1985). The annual rate of national deforestation is difficult to define precisely. Estimates range from the highest of 3,790 sq. km between 1972 and 1982 (Ganapin, 1986), 3,235 sq. km between 1970 and 1979 (FAO, 1981), to low estimates of 1,700 sq. km (Cox, 1988) or 910 sq. km (WRITHED, 1986). Existing tropical rain forest cover may be lost by the end of the century (Petocz, 1988). Mangroves, which covered some 4,500 sq. km in 1920, have been depleted both by legal and illegal felling over the last 60 years (Alvarez, 1984). Some 1,461 sq. km of mangroves remained in 1978 (Davies et al, 1990), but only 1,190 sq. km remained in 1990 (Penafiel, 1990). Only 814 sq. km can still be classified as undisturbed (Petocz, 1988) and cover is declining by 50 sq. km each year (Howes, 1987). Other major wetland habitats include estuariesmudflats, seagrass beds, lakes, freshwater swamps and marshes; a descriptive inventory of wetlands considered to be important for conservation is given by Davies et al, (1990). The Philippine fauna is exceptionally rich with some 960 terrestrial vertebrates. Many species are forest obligates and are acutely threatened by forest loss. Endemic collectively amounts to 43% of species, with 59% endemic mammals ( 1 00 species out of a total of 1 67) and as many as 85% of non-volant mammals (79 species) (Heaney, 1986; Petocz, 1988). There are 162 endemic bird species out of a total of 388 resident species (Bruce, 1980). Endemism is also unusually high in the 115