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3.2 Practices to Prepare and Improve Culture Environment . . . . . . . . . . ... Figure 4: Average change in volume of production in Philippine fisheries from. 1980 to ...

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Public Disclosure Authorized

An Overview of Agricultural Pollution in the Philippines The Fisheries Sector 2016

Public Disclosure Authorized

Public Disclosure Authorized

An Overview of Agricultural Pollution in the Philippines The Fisheries Sector 2016 Submitted to The World Bank’s Agriculture and Environment & Natural Resources Global Practices

© 2016 International Bank for Reconstruction and Development / The World Bank 1818 H Street NW Washington DC 20433 Telephone: 202-473-1000 Internet: www.worldbank.org This work is a product of the staff of The World Bank. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries. Rights and Permissions The material in this work is subject to copyright. Because The World Bank encourages dissemination of its knowledge, this work may be reproduced, in whole or in part, for noncommercial purposes as long as full attribution to this work is given. Any queries on rights and licenses, including subsidiary rights, should be addressed to World Bank Publications, The World Bank Group, 1818 H Street NW, Washington, DC 20433, USA; fax: 202-522-2625; e-mail: [email protected] Cite this report as: Cuvin-Aralar, M.L.A., C.H. Ricafort, and A. Salvacion. 2016. “An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector.” Prepared for the World Bank. Washington, D.C. Publication design and typesetting by The Word Express, Inc. Cover photos courtesy of istock.com and shutterstock.com.

CONTENTS Abbreviations and Acronyms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 History of Capture Fisheries and Aquaculture in the Philippines. . . . . . 1 1.2 Capture Fisheries and Aquaculture Development in the Philippines. . . 3 2 Increased Population and Drive for Economic Growth Pushed for Increasing Fisheries Production in the Philippines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.1 Population Pressure to Increase Fish Production from Capture Fisheries and Aquaculture. . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.2 Contribution of Capture Fisheries and Aquaculture in Philippine Economy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3 Approaches to Improve Fisheries Production Resulted in the Various Impacts and Became Sources of Environmental Problems and Pollution. . . . . . . . . . . . . . . . . . 21 3.1 Conversion of Land and Water Resources for Aquaculture . . . . . . . . . 21 3.2 Practices to Prepare and Improve Culture Environment . . . . . . . . . . . 24 3.3  Practices to Improve Production. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 3.4 Practices to Improve Aquatic Animal Health. . . . . . . . . . . . . . . . . . . . 29 3.5 Practice to Diversity Cultured Commodities. . . . . . . . . . . . . . . . . . . . 30 4  Physical Impacts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4.1  Environmental Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4.2 Impact of Diversification of Culture Commodities through Species Introductions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

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5 Socioeconomic and Health Impacts of Fisheries and Aquaculture Practices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 5.1 Human Health Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 5.2  Socioeconomic Impacts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 6  Solutions to Mitigate Impacts of Aquaculture Pollutants. . . . . . . . . . . . . . . . . 45 6.1 Use of Eubiotics and Strategies to Improve Health of Aquatic Animals. . . . . . . . . . . . . . . 45 6.2 Legislations and Regulations on the Use of Chemicals and Fisheries and Aquaculture. . . . 47 6.3 Regulations on the introduction of nonnative species for culture and protecting local species. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 6.4 Technologies to Reduce Nutrients from Aquaculture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 List of Figures Figure 1: Figure 2: Figure 3: Figure 4: Figure 5: Figure 6: Figure 7: Figure 8: Figure 9: Figure 10: Figure 11: Figure 12: Figure 13: Figure 14: Figure 15: Figure 16: Figure 17: Figure 18:

The Philippines’ total fisheries production compared to total world production from capture fisheries and aquaculture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Percentage contribution and rank of Philippine fisheries to world production. . . . . . . 4 Trend of fisheries production in the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Average change in volume of production in Philippine fisheries from 1980 to 2014. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Capture fisheries data for the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Average change in volume of production in Philippine capture fisheries from 1980 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Marine and inland capture fisheries data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Average change in volume of production in Philippine marine capture fisheries from 1980 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Average volume of production in Philippine marine capture fisheries from 1980 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Average volume of production in Philippine inland capture fisheries from 1980 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Average change in volume of production in Philippine inland capture fisheries from 1980 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Aquaculture production in marine, freshwater, and brackish-water culture environments (excluding aquatic plants) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Average volume of production in Philippine brackish-water aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Average change in volume of production in Philippine brackish-water aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Average volume of production in Philippine freshwater aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Average change in volume of production in Philippine freshwater aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Top aquaculture fishery commodities in Philippine aquaculture . . . . . . . . . . . . . . . . 10 Average volume of production in Philippine marine aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Contents

Figure 19: Figure 20: Figure 21: Figure 22: Figure 23: Figure 24: Figure 25: Figure 26: Figure 27: Figure 28: Figure 29: Figure 30: Figure 31: Figure 32: Figure 33: Figure 34: Figure 35: Figure 36: Figure 37: Figure 38: Figure 39: Figure 40: Figure 41: Figure 42:

Average change in volume of production in Philippine marine aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Volume of production in Philippine small-farm reservoir in 2014. . . . . . . . . . . . . . . 11 Average change in volume of production in Philippine peneid shrimp aquaculture from 1996 to 2014. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Average volume of production in Philippine peneid shrimp aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Average volume of production in Philippine tilapia aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Average change in volume of production in Philippine tilapia aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Average change in volume of production in Philippine milkfish aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Average volume of production in Philippine milkfish aquaculture from 1996 to 2014 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Philippine population growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Value of fisheries production in Philippine pesos from 1980 to 2014. . . . . . . . . . . . . 17 Contribution of fisheries to the Philippines’ GDP. . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Contribution of fisheries to GVA at constant prices. . . . . . . . . . . . . . . . . . . . . . . . . . 18 Comparison of value of exports and imports of fisheries products. . . . . . . . . . . . . . . 18 Import dependency ratio of three major fish culture commodities. . . . . . . . . . . . . . . 19 Production cost, farm gate price, and profit margins for milkfish culture. . . . . . . . . . 19 Process of establishment of MPs in the Philippines . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Site of MPs for establishment in the Philippines . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Number of aquatic animal species introductions in the Philippines in the various decades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 The loss of mangrove areas and the development of brackish-water ponds in the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Occurrences of fish kill in Taal Lake due to various factors including lake overturn, population, oxygen depletion, sulfur upwelling, and timud infestation based on BFAR announcements and reports from 1998 to 2011. . . . . . . . . . . . . . . . . . . . . 36 Schematic diagram of direct and indirect impacts of species introduction on biodiversity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Sources and pathways of how antibiotics are released into the environment. . . . . . . . 43 Schematic diagram of farm layout (top-top view; bottom-cross-sectional view) of rice-prawn culture in Laguna based on a 1,000 m2 area. . . . . . . . . . . . . . . . . . . . . 54 Cost and return for rice monoculture and rice-prawn integrated culture for a 1,000 m2 plot from pilot studies of the BFAR. . . . . . . . . . . . . . . . . . . . . . . . . . 54

List of Tables Table 1: Table 2: Table 3: Table 4: Table 5:

Estimated fish consumption, fish production, and surplus/deficit in the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Performance of two MPs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Groups of chemicals and additives used in aquaculture . . . . . . . . . . . . . . . . . . . . . . . 24 Application of inorganic fertilizer in shrimp Penaeus monodon and milkfish Chanos chanos ponds for the period surveyed in 1995–1996 and 2006–2007. . . . . . 26 Summary of organic fertilizers used in milkfish and shrimp ponds and in polyculture of these two commodities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

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Table 6: Table 7: Table 8: Table 9: Table 10: Table 11: Table 12: Table 13: Table 14: Table 15: Table 16: Table 17: Table 18: Table 19: Table 20:

Use and dosage of other chemicals to modify soil or water quality for aquaculture of milkfish and shrimp and polyculture of the two species. . . . . . . . . . . . . . . . . . . . . 27 Application of common piscicides and molluscicides in milkfish and shrimp culture and polyculture of these two commodities. . . . . . . . . . . . . . . . . . . . . 28 Sample of hormone dosage used for induced spawning of the Asian catfish Clarias microcephalus and bighead carp Aristichthys nobilis. . . . . . . . . . . . . . . . . . . 28 Common anesthetics and dosage used in common aquaculture species found in the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Antibiotic feed additives and their use and dosage as applied to shrimp culture. . . . . 29 Disinfectants used in black tiger shrimp brackish-water farms in the Philippines in 2006–2008* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Partial list of invasive and potentially invasive introduced species to the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Estimated organic matter and nutrient loading for one ton of harvested shrimp released at different FCRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Comparison of phosphorus values from marine aquaculture sites in the Philippines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Level of OTC, OXA, and OCP in fish samples from the Philippines . . . . . . . . . . . . 37 Production value (in PHP, thousands) of milkfish and tilapia as well as total cultured fish production in Laguna de Bay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Probiotics used in shrimp brackish-water farms in the Philippines. . . . . . . . . . . . . . . 46 Banned veterinary drugs in aquaculture feeds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 PNS for various fishery products. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 List of chemicals used in aquaculture and their status in the Philippines and other ASEAN member countries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

ABBREVIATIONS AND ACRONYMS AFMA Agriculture and Fisheries Modernization Act ASEAN Association of Southeast Asian Nations BFAR Bureau of Fisheries and Aquatic Resources BFT Biofloc Technology BW Body Weight CA Competent Authority CFA Committee on Fisheries and Aquaculture CHED Commission on Higher Education DA Department of Agriculture DENR Department of Environment and Natural Resources DOH Department of Health FAO Food and Agriculture Organization FCR Feed Conversion Ratio FLA Fishpond Lease Agreement FOS Fructooligosaccharides FPA Fertilizer and Pesticide Authority GAqP Good Aquaculture Practice GDP Gross Domestic Product GVA Gross Value Added HCG Human Chorionic Gonadotropin IAA Integrated Agri-Aquaculture ICMSF International Commission on Microbiological Specifications for Food IMTA Integrated Multitrophic Aquaculture KDF Potassium Diformate LGU Local Government Unit LHRHa Luteinizing Hormone Releasing Hormone-Analog MOS Mannanoligosaccharides MF Maintenance Feeding

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MP Mariculture Park MRL Maximum Residue Limit MT Methyltestosterone NDF Sodium Diformate NPK Nitrogen, Phosphorus and Potassium OA Organic Acid PCAF Philippine Council for Agriculture and Fisheries PEL Permissible Exposure Limit

PNS Philippine National Standards OCP Organochlorine Pesticides OTC Oxytetracycline OXA Oxalinic Acid SEAFDEC/AQD Southeast Asian Fisheries Development Center, Aquaculture Department SF Submaximum Feeding WHO World Health Organization

FOREWORD This report is part of a national overview of agricultural pollution in the Philippines, commissioned by the World Bank. The overview consists of three “chapters” on the crops, livestock, and fisheries sub-sectors, and a summary report. This “chapter” provides a broad national overview of (a) the magnitude, impacts, and drivers of pollution related to the fisheries sector’s development with a focus on aquaculture; (b) measures that have been taken by the public sector to manage or mitigate this pollution; and (c) existing knowledge gaps and directions for future research. This report was prepared on the basis of existing literature, recent analyses, and national and international statistics, as well as extensive interviews. It did not involve new primary research and did not attempt to cover pollution issues that arise in the broader aquaculture value chain, relating for instance to processing, packaging and transportation, feed processing, or veterinary drug factories.

INTRODUCTION

1.1 History of Capture Fisheries and Aquaculture in the Philippines There are limitations in the availability of historical data on capture fisheries in the Philippines. Fairly accurate national statistics on the country’s capture fisheries are relatively recent. Although it is difficult to clearly establish capture fishery practices in prehistoric times, ethnographic evidence shows that in Southeast Asia, its inhabitants have used some technical devices to obtain food from the sea. It is assumed that in the Philippines, coastal dwellers also engaged in fishing activities. Capture fisheries was limited to the land-water interface of the coastal areas and those of rivers and lakes. Early observations by colonizing Spaniards in the 1500s describe the barter-type relationship between fishermen who lived on the coast and farmers who lived in upland areas (Blair and Robertson 1903, as cited by Spoehr 1984). Historical records also show some semblance of control on marine fisheries resources in precolonial Philippines where village chiefs give permission to people outside their village to fish within the designated limits of their village after paying for the privilege (Blair and Robertson 1903, as cited by Spoehr 1984). During the Spanish colonial times, the control of the fishing areas came under the purview of the colonial government (Spoehr 1984). Specialized fishing villages/communities came about during the Spanish colonial times, with the subsequent growth of Manila and other towns providing established fixed markets for fishery products. In the early 1900s, fishing towns as they are known at present emerged, wherein their primary activity centered on catching, processing, bulking, and marketing of fish on a much larger scale compared to heretofore village-size fishing communities (Spoehr 1984). Thus, with a combination of population growth, technological advancement, and changes in economic structure, the small fishing villages evolved into fishing towns

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An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

and some areas into fish port and fish landing areas supporting large-scale commercial fishing. Capture fisheries technology in the Philippines also evolved through time. Early trades with China and the settlement of Chinese communities resulted in the introduction of some capture fisheries gears by this ethnic group, such as the large lever net or ‘salambaw’ as well as gill and casting nets (Rasalan 1952, as cited by Spoehr 1984). The capture fishing industry during the Spanish colonial times was relatively static from a technological standpoint. In the late 1800s, Tagalog innovations such as a type of round haul seine ‘sapiao’ and a deepwater fish corral spread to the archipelago (Umali 1950, as cited by Spoehr 1984). In pelagic fishing, more innovations such as a type of purse seine, gill net, and lift net were adopted. Japanese commercial fishing innovations such as the beam trawl and ‘muro-ami’ were introduced. With these innovations, the Philippines’ capture fisheries transformed from a broad-spectrum, small-scale type to more capital-intensive and highly specialized fish-catching methods. The period since World War II has seen the greatest technological advances in capture fisheries in the country than any other period before that (Spoehr 1984). Details on the early history of aquaculture are unclear, although people have been farming fish for thousands of years based on evidence of fish farming in the Arab Republic of Egypt and China in 2500 BC and 1100 BC, respectively (Landau 1992). In Southeast Asia, brackish-water pond culture can be traced from Indonesia almost 600 years ago (Schuster 1952, as cited by Primavera 1995). This gradually spread to other Southeast Asian countries. In the Philippines, the earliest fishpond record was in Rizal Province in 1863 (Philippine Census of 1921 in Siddall, Atchue, and Murray 1985). At the turn of the century, there were reports of pond culture in the Manila area (Radcliffe 1912, as cited by Primavera 1993). Traditional aquaculture involved minimal inputs, small farm size, and low stocking density. This type of fish farming has been practiced in many parts of the world for centuries. Intensification of aquaculture

is a consequence of rapid population growth accompanied by increased demand for fish and fishery products since production from capture fisheries has become increasingly unable to meet the demand due to a variety of factors, foremost of which are over exploitation and the depletion of natural stocks (Sapkota et al. 2008). In Southeast Asia, the early development of aquaculture first started in the 15th century in Indonesia with brackish-water culture and spread to neighboring countries. The Philippines being an archipelago, with more water than land like Indonesia, followed suit. Expansion of the aquaculture industry in the Philippines was further stimulated with the establishment of the Bureau of Fisheries and Aquatic Resources (BFAR) in the late 1940s. The BFAR established and implemented schemes to promote aquaculture through the construction of ponds (Primavera 1995). Since then, aquaculture has evolved in the country with a diverse list of species cultured in a variety of ecosystems. The bulk of the production is from aquatic plants (seaweeds), milkfish, tilapia, shrimp, carp, and bivalves like oyster and mussel. Like capture fisheries, aquaculture has significantly contributed to food security and rural livelihood. The Philippines ranked 4th with regard to aquaculture production in 1997, but dropped to 12th place by 2012 (FAO 2014) and moved slightly to 11th place in 2013 (FAO FishStat 2015). Milkfish was the primary coastal aquaculture commodity cultured in brackish-water ponds, with Food and Agriculture Organization (FAO) records dating back to 1950. The culture of this euryhaline species spread to freshwater and by the 1990s to marine cages. Hand in hand with developments in the technology of milkfish culture and success in the captive breeding of the commodity pioneered by the Southeast Asian Fisheries Development Center/Aquaculture Department (SEAFDEC/AQD) (Marte and Lacanilao 1986; Juario et al. 1984) coupled with the promotion of the culture of the commodity by the locals, the production of the commodity spread to other areas of the country. The culture of peneid shrimps, mainly the black tiger shrimp Penaeus monodon, evolved from

Introduction

traditional, to extensive, to semi-intensive, and finally to an intensive farming system (Primavera 1991). From being a by-product (from accidental entries into ponds) of milkfish aquaculture, the tiger shrimp industry developed as a separate and important aquaculture commodity. Traditional and extensive culture shrimp farming systems relied on tidal water exchange and available natural productivity since stocking rates are quite low from less than 1 prawn/m2 (traditional) to 1–3 prawns/ m2 (extensive) and maybe in polyculture with milkfish.

1.2 Capture Fisheries and Aquaculture Development in the Philippines The Philippines’ fisheries production, capture and aquaculture combined, has steadily increased since the 1950s. From 0.230 million tons in 1950, the production steadily increased to 5.158 million tons, an equivalent average growth of 22.4-fold. However, there was a slight decrease in total production from 2011 to 2013 (Figure 1). The percentage contribution of the Philippines’ fisheries to world production ranged from 1.2 percent in 1950 to 3.1 percent in 2010. The country’s world ranking also improved with its percentage contribution,

from 17 in 1950–1965 to 5 in 2010. In 2013, the country ranked eighth in the world (Figure 2). The contribution of aquaculture to the country’s production has increased dramatically from just 10.7 percent (25,649 tons) in 1950 to 50.4 percent (4,708,790 tons) in 2013, including aquatic plants (Figure 3). Despite advances in aquaculture, there was −4 percent growth in the fisheries sector for the period 2013 to 2014 compared to 1.2 percent growth in the agriculture and forestry sector for the same period (PSA 2015). Among the 81 provinces in the country, Palawan exhibited the fastest increase in production in the last 34 years. Palawan set an average annual increase of 14,000 tons in production from the years 1980 to 2014. This is way higher when compared to the 1980s’ top producer, Laguna, which rather suffered from an average annual decrease of 5,000 tons in production for the same period (Figure 4).

1.2.1  Capture Fisheries The average growth of the Philippine marine capture fisheries from 2003 to 2012 is just 4.6 percent. This is low in comparison to China (13.6 percent), Indonesia (27 percent), and Vietnam (46.8 percent) for the same

Production, tons (x 1,000,000); Phil. Production, tons (x 100,000)

Figure 1:  The Philippines’ total fisheries production compared to total world production from capture fisheries and aquaculture 200 180 160 140 120 100 80 60 40 20 0

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2011 2012 2013 World production

Source: FAO FishStat 2015.

3

Philippine production

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An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

3.5%

1

3.0%

3 5

2.5%

7

2.0%

9

1.5%

11

1.0%

13

0.5%

15

0%

World Ranking

Contribution to World Production

Figure 2:  Percentage contribution and rank of Philippine fisheries to world production

17 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2011 2012 2013 Contribution, %

World Rank

Source: FAO FishStat 2015.

period. Myanmar with 121.4 percent has the highest growth in the world (FAO 2014). Based on FAO FishStat (2015), total capture fisheries in the Philippines peaked in 2010 with 2,615,801 tons, equivalent to a more than 12-fold increase from 213,227 tons in 1950 (Figure 5). In 2014, the total production declined to 2,351,479 tons. This corresponds to about 10 percent decrease in production relative to the 2010s. At the

provincial level, Laguna exhibited the fastest decline in production from 1980 to 2014 (Figure 5). On the other hand, South Cotabato achieved an average annual increase of 7,000 tons in production for the same period, making it the highest contributor in capture fisheries. Ninety percent of the total production in capture fisheries is attributed to marine commodities and the remaining 10 percent to inland capture fisheries

Figure 3:  Trend of fisheries production in the Philippines

Volume of Production, million of metric tons

6 5 4 3 2 1 0

1950 1953 1956 1959 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 2010 2013 Capture

Source: FAO FishStat 2015.

Aquaculture

Total

Introduction

5

Figure 4:  Average change in volume of production in Philippine fisheries from 1980 to 2014

Figure 6:  Average change in volume of production in Philippine capture fisheries from 1980 to 2014

Source: Based on PSA 2015 data.

Source: Based on PSA 2015 data.

Figure 5:  Capture fisheries data for the Philippines

based on the data of FAO FishStat from 1950 to 2013 (Figure 7). The major provinces contributing to marine capture fisheries are shown in Figure 8. Laguna Province is one of the main players in inland capture fisheries. In 2014, the province contributed 19 percent to the total production in inland capture fisheries next to Rizal (28 percent), mainly due to production from the country’s largest inland water body, Laguna de Bay, bounded by these two provinces (Figure 10). However, it is in this specific subsector that Laguna had the fastest decline in total production in capture fisheries from 1980 to 2014 as shown in Figure 11.

Volume of Production, million of metric tons

3.0 2.5 2.0 1.5 1.0 0.5 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015

0

Source: FAO FishStat 2015.

6

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Figure 7:  Marine and inland capture fisheries data

Volume of Production, million of metric tons

3.0

Figure 8:  Average change in volume of production in Philippine marine capture fisheries from 1980 to 2014

2.5 2.0 1.5 1.0 0.5 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015

0

Inland

Marine

Source: FAO FishStat 2015.

1.2.2  Aquaculture From the 1950s to 1970s, brackish-water aquaculture dominated the fish culture scene, contributing to 87 percent of total production while the remaining was mainly from freshwater aquaculture (Figure 12).

Source: Based on PSA 2015 data.

Figure 9:  Average volume of production in Philippine marine capture fisheries from 1980 to 2014

Source: Based on PSA 2015 data.

Introduction

7

Figure 10:  Average volume of production in Philippine inland capture fisheries from 1980 to 2014

Source: Based on PSA 2015 data.

In 2014, 15 percent of the 322,668 tons of production in brackish-water aquaculture came from Pampanga (Figure 13). In line with this, it was reported to have an average annual increase of 1,000 tons in production in the last 18 years (Figure 14). Moreover, Pampanga also contributed the most in freshwater aquaculture, but in much greater volume. In 2014 alone, the province produced 103,131 tons (35 percent) of cultured fish from freshwater farms (mainly fishponds) or about the same as the combined production of Batangas (22 percent) and Rizal (16 percent) as shown in Figure 15. Freshwater aquaculture production in the country increased to 299,000 tons in 2014 as compared to just 3,300 tons in 1950. Pampanga, along with Batangas and Rizal, are the fastest-growing provinces with regard to production in freshwater aquaculture. On the other hand, marine aquaculture was generally confined to seaweeds and other aquatic plants up until the early 1970s. However, since then marine fish aquaculture grew in volume and by 2014, marine fish production from aquaculture contributed almost 125,000 tons compared to a measly 38 tons in 1972 (Figure 17). Seventy-six

Figure 11:  Average change in volume of production in Philippine inland capture fisheries from 1980 to 2014

Source: Based on PSA 2015 data.

8

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Volume of Production, million of metric tons

Figure 12:  Aquaculture production in marine, freshwater, and brackish-water culture environments (excluding aquatic plants) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1950 1953 1956 1959 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 2010 2013 Brackish

Freshwater

Marine

Source: FAO FishStat 2015.

percent of this came from Pangasinan alone. As the top contributor in marine fish aquaculture, Pangasinan had an average annual increase of 5,000 tons in production from 1996 to 2014 (Figure 18).

In addition, small-farm reservoirs are also present in the country, which produced almost 100 tons of cultured fish annually. These mainly came from Quirino and North Cotabato (Figure 19).

Figure 13:  Average volume of production in Philippine brackish-water aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

Introduction

Figure 14:  Average change in volume of production in Philippine brackish-water aquaculture from 1996 to 2014

Figure 16:  Average change in volume of production in Philippine freshwater aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

Source: Based on PSA 2015 data.

9

Figure 15:  Average volume of production in Philippine freshwater aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

10

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Volume of Production, million of metric tons

Figure 17:  Top aquaculture fishery commodities in Philippine aquaculture 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1950 1953 1956 1959 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001 2004 2007 2010 2013 Others

Shrimps

Milkfish

Tilapias

Source: FAO FishStat 2015.

Dominant fish species cultured are peneid shrimps (mainly tiger shrimps), tilapias (mainly Nile tilapia), and milkfish. These three commodities comprised 77 percent of fish aquaculture production by 2013 at a

total volume of 730,000 tons and at an estimated total value of US$1.8 million (Figure 20). From these three commodities, with the development of aquaculture technologies for other aquatic

Figure 18:  Average volume of production in Philippine marine aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

Introduction

Figure 19:  Average change in volume of production in Philippine marine aquaculture from 1996 to 2014

11

Figure 21:  Average change in volume of production in Philippine peneid shrimp aquaculture from 1996 to 2014

Source: Based on PSA 2015 data. Source: Based on PSA 2015 data.

Figure 20:  Volume of production in Philippine small-farm reservoir in 2014

Source: Based on PSA 2015 data.

food species, the list of aquaculture commodities expanded by the 1980s to include crabs and snappers. By 2013, the list included groupers and siganids. Peneid shrimps were produced in brackish-water and marine culture systems, with peak volume in 1993 close to 96,000 tons. Thereafter, production sharply declined to a low of less than 38,000 tons in 1998, equivalent to only 40 percent of its peak production. The decline was due to the onset of devastating diseases which decimated the shrimp industry not only in the country but in many shrimp-producing countries as well. At the provincial level, Negros Occidental suffered the most with a 95 percent decrease in production from 1996 to 1998. The production of the said province continues to decline by an average of 991 tons each year. From the 18,000 tons of production in 1996, Negros Occidental produced only 46 tons of peneid shrimps in 2014 (Figure 21).

12

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Figure 22:  Average volume of production in Philippine peneid shrimp aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

But then again, the country’s production gradually picked up. As of 2014, however, it has not yet fully recovered with just 51,000 tons of production valued at US$500,000. This increase can primarily be attributed to Pampanga, which produced 20,000 tons (39 percent) of peneid shrimps in 2014. This is followed by Lanao del Norte with 10,000 tons (21 percent) of production as presented in Figure 22. In line with this, Pampanga also surpassed 80 other provinces in the country by producing 100,000 tons of tilapia. It is equivalent to 41 percent of the total tilapia produced in 2014. It is 50 percent higher when compared to the second-highest producer, Batangas (Figure 23). Tilapia culture started off with the Mossambique tilapia (Oreochromis mossambicus) and was gradually replaced by Nile tilapia (Oreochromis niloticus) (Gupta and Acosta 2004). A number of genetic improvement programs for Nile tilapia have been undertaken by various government institutions as well as universities. The GIFT, Get Excel, FAST, and GMT are just a few of

the strains developed in the Philippines. A few of these technologies and strains are now being used in other tilapia-producing countries. (Macaranas et al. 1995; Bolivar et al. 1993). Milkfish (Chanos chanos) on the other hand is a commodity with wide salinity tolerance, making it ideal for culture in all three aquaculture environments: marine, brackish, and freshwater farming systems. From 1950 to the mid-1990s, based on FAO records (FishStat), milkfish was cultured mainly in brackish-water ponds with about a tenth of total production from freshwater aquaculture. The culture of milkfish in fish pens in Laguna de Bay, the largest inland water body in the country, started in the early 1970s (Delmendo and Gedney 1976) and gradually spread to other inland water bodies like Taal Lake (Tan, Garcia, and Tan 2011) (Figure 25). By 2013, total milkfish production in the three culture environments was at its highest at over 401,000 tons, in which 25 percent came from Pangasinan alone (Figure 26).

Introduction

13

Figure 23:  Average volume of production in Philippine tilapia aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

Figure 24:  Average change in volume of production in Philippine tilapia aquaculture from 1996 to 2014

Figure 25:  Average change in volume of production in Philippine milkfish aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

Source: Based on PSA 2015 data.

14

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Figure 26:  Average volume of production in Philippine milkfish aquaculture from 1996 to 2014

Source: Based on PSA 2015 data.

INCREASED POPULATION AND DRIVE FOR ECONOMIC GROWTH PUSHED FOR INCREASING FISHERIES PRODUCTION IN THE PHILIPPINES

2.1 Population Pressure to Increase Fish Production from Capture Fisheries and Aquaculture The Philippines’ population tripled from 30.9 million in 1965 to 92.3 million in 2010 (PSA 2015). It is projected to be 101.45 million by the end of 2015 and if current growth continues, it may reach 110.97 million in 2020, 130.47 million in 2030, and 142.73 million in 2045 (Figure 27, Trading Economics 2015). Population growth rate has slowed down—the growth rate for the period 2000–2010 was 1.9 percent compared to 2.34 percent for the period 1990–2000 (PSA 2015). The increase in population is accompanied by increase in fish consumption. The continued increase in the country’s population (Figure 27) was accompanied by an increase in total fish production (Figure 3), with aquaculture’s contribution increasing significantly in the last decade.

2

16

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Figure 27:  Philippine population growth 120

Million

100 80 60 40 20

1969

1980

1991

2002

2013

Source: Trading Economics 2015.

In 1965, fish consumption of Filipinos was at 23.09 kg/capita/year. This increased to 31.58 kg/capita/year by 2013, with the highest consumption of 35.64 kg/capita in 2010 (Table 1). This translates to a total fish consumption of 3.1 tons in 2013 and 3.3 tons in 2010. If the country’s population grows as expected, with a population projection of 110.97 million in 2020, fish consumption would reach 3.5 tons using the

average consumption for the last four decades which is close to 32 kg/capita/year. With regard to self-sufficiency in fish production compared with fish consumption, there was a deficit from 1961 to 1975. To address the deficit in fish supply for local consumption, various programs to improve capture fisheries and aquaculture production were undertaken by the Government’s BFAR through

Table 1:  Estimated fish consumption, fish production, and surplus/deficit in the Philippines Year

Per Capita Fish Consumption, kg/year

Total Fish Consumption, tons

Total Fish Production, tons

Surplus/Deficit, tons

1961

23.04

625,881.60

500,047.0

(125,834.6)

1965

25.79

797,246.27

715,638.0

(81,608.3)

1970

33.58

1,202,331.90

1,102,316.0

(100,015.9)

1975

37.40

1,544,470.40

1,466,241.0

(78,229.4)

1980

32.43

1,537,117.14

1,708,683.0

171,565.9

1985

32.87

1,785,662.75

2,048,587.0

262,924.3

1990

35.64

2,207,862.36

2,500,183.0

292,320.6

1995

31.59

2,198,88C.13

2,801,499.0

602,613.9

2000

28.83

2,238,707.16

2,997,051.0

758,343.8

2005

32.75

2,810,637.75

4,165,586.0

1,354,948.3

2010

35.64

3,330,344.16

5,157,735.0

1,827,390.8

2013

31.58

3,107,250.94

4,705,107.0

1,597,856.1

Source: Fish Consumption Data from PSA (2015) and Fish Production Data from FAO (2015).

Increased Population and Drive For Economic Growth Pushed For Increasing Fisheries Production In The Philippines

17

Figure 28:  Value of fisheries production in Philippine pesos from 1980 to 2014 Value of Production, million PhP

300 250 200 150 100 50 0

1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 Aquaculture

Capture Fisheries

Total

Source: PSA 2015.

its Ginintuang Masaganang Ani for Fisheries Program for 2002–2004, with specific developmental road maps for various commodities (BFAR 2015).

2.2 Contribution of Capture Fisheries and Aquaculture in Philippine Economy The fisheries sector contributed almost PHP 242 million in 2014 to the country’s economy (Figure 28).

This translates to 1.9 percent in 2013, down from a peak of 4.9 percent in 1987 at constant prices, with an average of 4.0 percent since 1978. This is in line with a sharp drop in the gross domestic product (GDP) contribution starting in 2010 (Figure 29). With regard to gross value added (GVA) contribution, the fisheries sector contributed 18.5 percent in 2013, with a high of 24.4 percent in 2009 (since 1988) and an average of 20 percent at constant prices (Figure 30). On the other hand, fishery exports far exceeded imports with a balance of trade of US$1,086 million

Figure 29:  Contribution of fisheries to the Philippines’ GDP

GDP at Constant Price

6 5 4 3 2 1 0

1978 1980 1982 1985 1988 1990 1992 1994 1996 1998 2000 2003 2005 2007 2009 2011 2013

Source: BFAR 1978 to 2013.

18

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Figure 30:  Contribution of fisheries to GVA at constant prices

20 15 10

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

1990

0

1989

5

1988

GVA at Constant Price, %

25

Source: BFAR 1988 to 2013.

in 2013 (Figure 31). Major exports in terms of value are tuna, seaweeds, crabs, and shrimps, equivalent of 28.91 percent, 9.48 percent, 3.65 percent, and 2.86 percent, respectively, as of 2013 (BFAR 2013). Of the three top fish commodities cultured, import dependency ratio is relatively high for shrimps and prawns and low for milkfish and tilapia (Figure 32). In the last three decades, employment or engagement in the fisheries and aquaculture sector has grown faster than the world’s population and employment in traditional agriculture. Eighty-six percent of fishers and

fish farmers worldwide live in Asia. China, India, Indonesia, the Philippines, and Vietnam have a significant number of fishers and fish farmers (FAO 2008). Most fishers and fish farmers are small-scale, artisanal fishers, operating on coastal and inland fishery resources. In the Philippines, about a million people are employed in the fisheries and fish farming sector. Available census data show that in the 1990s, 990,872 people were under this sector, which is estimated at 5 percent of the country’s population. Fishermen in the municipal fisheries sector consisted 68 percent (675,677). Those involved in

Value, billion PhP

Figure 31:  Comparison of value of exports and imports of fisheries products 45 40 35 30 25 20 15 10 5 0

1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2000 2001 2003 2005 2007 2009 2011 2013 Exports

Source: BFAR 1977 to 2013.

Imports

19

Increased Population and Drive For Economic Growth Pushed For Increasing Fisheries Production In The Philippines

0.18 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0 1990

1992

1994

1996

1998

2000

Milkfish

2002

Tilapia

2004

2006

2008

2010

2012

2014

9 8 7 6 5 4 3 2 1 0

Import Dependency Ration Shrimps

Import Dependency Ration Milkfish and Tilapia

Figure 32:  Import dependency ratio of three major fish culture commodities

Shimps and Prawns

Source: PSA 2015.

aquaculture and commercial fisheries sectors comprise 26 percent (258,480) and 6 percent (56,715), respectively (BFAR 19977–2014). In the 2002 census, the number of people involved in fisheries increased to more than 1.6 million. There was a marked increase in the number of people employed in the municipal fisheries sector at close to 1.4 million people (85 percent), while aquaculture was slightly down to 226,195 (14 percent) and the commercial sector further reduced to just 16,498 (1 percent) (BFAR 1977–2014).

Those engaged in the culture of milkfish know the profitability of this enterprise. Milkfish aquaculture profit margins averaged 110 percent and were in the range of 63 to 153 percent between 2001 and 2013 (Figure 33). Production cost remained fairly constant from 2001 in the range of PHP 23.5–39.2 per kilogram, while farm gate price tended to increase from a low PHP 53.5 per kilogram to a high PHP 87.7 per kilogram.

100 90 80 70 60 50 40 30 20 10 0

200 150 100 50

2001

2002

2003

2004

2005

Production cost per Kg, Ph Source: PSA 2015.

2006

2007

2008

2009

Farmgate price per Kg, PhP

2010

2011 Profit, %

2012

2013



Profit, %

Cost, PhP

Figure 33:  Production cost, farm gate price, and profit margins for milkfish culture

APPROACHES TO IMPROVE FISHERIES PRODUCTION RESULTED IN THE VARIOUS IMPACTS AND BECAME SOURCES OF ENVIRONMENTAL PROBLEMS AND POLLUTION

3.1 Conversion of Land and Water Resources for Aquaculture The spread of aquaculture resulted in the conversion of natural water bodies into husbandry-type production of fish through the establishment of marine cage clusters (as mariculture parks [MPs]) and fish pens and cages in inland water bodies such as lakes and rivers. Land has been excavated and converted into fishponds.

3

22

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

3.1.1  Conversion of Mangroves to Fishponds At least 35 percent of the world’s mangrove forests have been lost in the last two decades, which far exceeds the loss of two other significantly threatened environments: tropical rain forests and coral reefs (Valiela, Bowen, and York 2001). Mangrove areas in the Philippines were around 400,000 to 500,000 ha at the turn of the century (Brown and Fisher 1918, as cited by Primavera and Agbayani 1997). This declined to 132,000 ha by 1990 (Auburn University 1993, as cited by Primavera and Agbayani 1997). The decrease in mangrove area in the last few decades has been traced back to the conversion of these areas into milkfish and shrimp ponds. There was only around 61,000 ha of fishponds in the 1940s. This expanded to 223,000 ha by 1990 (Primavera 1994) at the peak of fishpond construction from mangrove areas, between 1988 and 1990 alone. Initially, milkfish monoculture dominated the brackish-water pond system, but the development of culture technologies for the peneid shrimp Penaeus monodon, or black tiger shrimp, transformed many of these converted mangrove areas to the culture of this high-value commodity with excellent export potential.

3.1.2  Establishment of Mariculture Parks The Philippines’ BFAR spearheaded the establishment of MPs in selected coastal areas of the country. The concept of an MP is similar to the establishment of an industrial estate on land where the Government in partnership with the local Government and private sector puts up the facilities for a managed marine aquaculture enterprise. The rationale behind the establishment of MPs is to address issues such as declining capture fisheries due to over exploitation, destructive fishing methods, pollution, and habitat deterioration. The MP project aims to (a) generate employment and alleviate poverty in the countryside; (b) promote marine fish culture as an alternative livelihood for marginalized fisherfolk; (c) develop an area with appropriate

Figure 34:  Process of establishment of MPs in the Philippines Initial environment assessment An Executive Management Council manages the MP

Sanguniang Bayan/Panglunsod enacts an ordinance declaring the area as MP BFAR and LGU sign a MOA to develop and co-manage the MP

If site is suitable

If LGU and BFAR agree

Source: Adora 2009.

infrastructure and equipment that will allow fisherfolk and investors to operate in a cost-effective and secure manner; and (d) promote environment-friendly inputs and farm management practices. A ‘mariculture highway’ in the eastern and western seaboard of the country was envisioned to provide a sustainable strategy to ensure food security from aquaculture and to contribute to the country’s economic growth. These planned MPs will prevent the unregulated establishment of mariculture facilities across the country without regard for the overall sustainability of the industry. Figure 34 shows the process for establishing an MP in a designated area. Careful site evaluation is done before a site is considered for MP development. If the site is found suitable, the local Sanguniang Bayan or Sanguniang Panlungsod enacts an ordinance declaring the area as an MP. If the BFAR and the local government unit (LGU) involved agree, a memorandum of agreement is signed by the BFAR and the LGU to develop and co-manage the MP. An Executive Management Council manages the MP. The first MP in the Philippines was established in 2001 in the Island Garden City of Samal in Davao. Since then a number of mariculture areas have been developed (Figure 35). Table 2 shows the operation of two MPs, one in Panabo and another in San Juanico. Aside from the production and economic benefits of these two MPs,

Approaches to Improve Fisheries Production

Figure 35:  Site of MPs for establishment in the Philippines

23

Table 2:  Performance of two MPs Parameter

Panabo MP

San Juanico MP

1,075

2,700

Fish cages, no.

323

168

Production, tons

1,855.03

3,539.785

Milkfish

Milkfish

Jobs generated, no.

425

304

Investors from ancillary industry, no.

61

178

2006 to 2009

2004 to 2009

Area, ha

Commodity

Year of data covered Source: Adora 2009.

Source: BFAR website.

fisherfolk in the area noted increased fish recruitment and reduction, if not elimination, in unregulated, illegal, and destructive fishing in the area, probably due to active management of the MP and its surrounding areas. The total area planned for MP development is 50,150 ha, but only a small portion of this has been fully established (Salayo et al. 2012).

3.1.3  Establishment of Inland Water Aquaculture Facilities The declining fish catch in the Philippines’ largest lake, Laguna de Bay, provided the impetus for the introduction of milkfish culture in fish pens in this lake. Heretofore, milkfish has been primarily cultured in

brackish-water ponds. Milkfish was thought to be an ideal species to utilize the eutrophic lake’s primary productivity since milkfish is an herbivorous species. The first fish pens was established as a pilot project of the BFAR and from a 40 ha pilot area in 1971, expanded to a peak of almost 29,011 ha in 1985 (Delmendo 1987). The initial success of the milkfish culture in Laguna de Bay resulted in the adoption of aquaculture in pens and cages in other inland water bodies in the country. The culture of Nile tilapia and bighead carp (Aristichthys nobilis) in Laguna de Bay and other lakes followed. The infrastructure of fish cages and pens in inland water bodies for aquaculture had adverse impacts on the environment. Cage and pen structures affect water bodies since (a) they take up space which essentially competes with other uses of the inland water body; (b) they alter flow regimes and circulation pattern which in turn affects oxygen, sediment, as well as plankton and fish larvae; and (c) they adversely alter the aesthetic quality of the area (Beveridge 1984). Enclosures such as pens and cages are a more open-type of fish rearing system than land-based facilities such as ponds, tanks, and raceways; thus, there is a greater degree of interaction between cages and penned fish and the outside environment (Beveridge 1984). Nutrients from unconsumed feeds, excreta, and the inevitable mortalities inside the pens/cages may directly affect the aquatic environment, often resulting in eutrophication.

24

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

3.2 Practices to Prepare and Improve Culture Environment With the intensification of aquaculture, the use of chemicals and other products during different phases of production has become inevitable. Fertilizers, water and soil treatment chemicals, disinfectants, antibiotics, and pesticides (molluscicides, piscicides, algicides) are among the most common groups of compounds used in aquaculture. Table 3 lists these various compounds used in Philippine aquaculture.

Table 3:  Groups of chemicals and additives used in aquaculture Group

Compound/Product

Reference

Inorganic fertilizers

Ammonium phosphate

a, c

Ammonium sulfate

a, c

Organic fertilizers

Calcium nitrate

a

Diammonium phosphate

c

Nitrogen, phosphorus and potassium (NPK)

a

Horse manure

a

Diazinon

a

Trichlorfon

c

Nicotine Rotenone Saponin (teaseed cake) Disinfectants

Calcium hypochlorite

a, c

Calcium sulfite

a

Copper complex solution

a a

Potassium monopersulfate

a

Potassium permanganate

a

Sodium cyanide

c

Sodium hypochlorite

a

Macrolides

 

Erythromycin Nitrofurans

Cow manure

a, c

Nifurpirinol Quinolones

Pig manure

a, c

Oxolinic acid

Urea

a, c

Sulfonamides

Calcium carbonate Dolomite

b, c

Iodine

Furazolidone

c

a a, b, c a

Formaldehyde

Antibiotics

a, c

Benzalkonium chloride

a, c

Treatment compound Calcium hydroxide

Pesticides

Azinphos-methyl

Chicken manure Molasses (sugar waste)

Water and sediment

c

Reference

Piscicides

Table 3:  Groups of chemicals and additives used in aquaculture Group

Compound/Product

a, b, f, g   a, b, c, f a   a, b, f, d, g  

Sulfamethoxazole

a

a, c

Sulfamerazine

a

a, c

Sulfadimethoxine

a

a, b, c

Sodium thiosulfate

a

Tetracyclines

 

Zeolite

a

Tetracycline

a

Doxycycline

Fungicides Fentin acetate

c

Malachite green

a

Trifluralin

a

Herbicides 2,4-Dichlorophenoxyacetic acid

a

Insecticides Organochlorine Endosulfan Organophosphate

a, c

Oxytetracycline (OTC) Others Chloramphenicol

a a, b   a, b, e, f, g

Nalidixic acid

a

Rifampicin

a

Trimethoprim

a

Source: Rico et al. 2012, © Wiley Publishing Asia Pty Ltd; Sapkota et al. 2008, (c) Elsevier. Reproduced with permission from publishers; further permission required for reuse. Note: a - Cruz-Lacierda, dela Peña and Lumanlan-Mayo 2000; b - Tendencia and de la Peña 2001; c - Cruz-Lacierda et al. 2008; d - Inglis et al. 1997; e - Graslund and Bengtsson 2001; f - Primavera 1993; g - Primavera et al. 1993.

Approaches to Improve Fisheries Production

3.2.1  Application of Fertilizers and Other Chemicals Asia has a long history of organic and inorganic fertilizer use in pond culture. Often, in extensive systems, fertilizers are the only input, most especially in smallscale, single pond operation. Almost all extensive and semi-intensive aquaculture, with few exceptions, rely on fertilizers and manure (de Silva and Hassan 2007). The Philippines imports most of its fertilizer needs as self-sufficient supply is only available for diammonium phosphate. Chicken manure is the most readily available and therefore the most commonly used organic fertilizer. Low-cost, unprocessed organic fertilizers are preferred by Philippine aquaculture operations, but the use of compost has also become popular. The Philippine Government has strongly supported the fertilizer industry with its deregulation in 1986 to encourage the entry of more traders. Quality assurance and monitoring, price control, and incentives are being implemented in line with the Agriculture and Fisheries Modernization Act (AFMA) under Republic Act 843C (Sumagaysay-Chavoso 2007). In pond culture, inorganic and organic fertilizers are applied in extensive and semi-intensive systems to stimulate growth of natural food. In extensive production systems, application of fertilizers allows for the growth of natural food in sufficient quantity to completely do away with commercial feeds. Extensive systems require heavy inputs of fertilizers since the growth of natural food should be sufficient to support fish growth, while semi-intensive and intensive systems require less fertilizers since the cultured fish are provided with formulated feeds (Cruz-Lacierda et al. 2008). Monoammonium phosphate (16-20-0), diammonium phosphate (18-46-0), urea (46-0-0), and ammonium sulfate (21-0-0) are the most widely used fertilizers in Philippine aquaculture. In combination with lime, ammonium sulfate is also used to kill unwanted species as part of pond preparation before stocking. Table 4 shows the use of various organic fertilizers in milkfish (Chanos chanos) and peneid shrimp (Penaeus monodon) ponds in the Philippines based on results of surveys in 1995–1996

25

(Cruz-Lacierda, de La Pena, and Lumanlan-Mayo 2000) and in 2006–2007 (Cruz-Lacierda et al. 2008). Organic fertilizers, mainly animal manure, is also widely used in Philippine aquaculture. A wide variety of animal waste and their combination is used. Chicken manure is the most widely used and as per survey results between 2006 and 2007, 85 percent of the 39 respondents use this organic fertilizer for their milkfish ponds while none of the 40 respondents engaged in shrimp culture use this organic fertilizer. Cow and carabao manure are also used by 3 percent of respondents for milkfish and 13 percent of respondents for shrimp culture. Horse manure is used by only 3 percent of the respondents for shrimp culture while pig manure is used by 5 percent of respondents for the polyculture of milkfish and shrimp (Cruz-Lacierda et al. 2008). Table 5 shows a summary of the organic fertilizers used in aquaculture from two survey periods: 1996–1997 (Cruz-Lacierda, de La Pena, and Lumanlan-Mayo 2000) and 2006–2007 (Cruz-Lacierda et al. 2008). With regard to use of organic fertilizers, there is a large increase in the rate of application for both the pond preparation phase based, for example, for chicken manure, from 0.5 to 3 tons/ha in 1995–1996 to 1–10 tons/ha in 2006–2007 for milkfish culture. Aside from fertilizers, there are other chemicals used in the preparation of ponds before stocking to improve soil and water quality. These chemicals act as soil or water conditioner. Lime is applied to adjust the pH of the pond soil to neutral or alkaline to promote volatilization of ammonia. Lime is also a disinfectant. Application is broadcasting on dried and caked pond bottom. Commonly used types of lime in pond preparation are agricultural lime (CaCO3), hydrated lime (Ca(OH)2), and dolomite (MgCO3). For soils with very low pH and for new ponds, hydrated lime is the choice, while agricultural lime is for old ponds (Cruz-Lacierda et al. 2008). To a limited extent some farmers even use liming to kill potential pests and predators. To remove ammonia and other nitrogenous compounds, zeolite is applied (Rico et al. 2012). Many of these water and soil conditioning chemicals have

26

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Table 4:  Application of inorganic fertilizer in shrimp Penaeus monodon and milkfish Chanos chanos ponds for the period surveyed in 1995–1996 and 2006–2007 Fertilizer

Commodity/Phase

1995–1996

2006–2007

Monoammonium phosphate (16-20-0)

Shrimp/pond preparation (broadcast)

4–100 kg/ha

9–100 kg/ha

Shrimp/rearing phase (periodic broadcast)

150–300 kg/ha



Milkfish/pond preparation

100–300 kg/ha

40–240 kg/ha

3.2 kg/ha (every 15 days till harvest)

20–100 kg/ha

Shrimp/pond preparation

3.2–50 kg/ha

3–120 kg/ha

Shrimp/rearing phase

0.6–20 kg/ha

Milkfish/pond preparation Broadcast

50–150 kg/ha

40–240 kg/ha



6–10 kg/ha

7.5–15 kg/ha

10–20 kg/ha

3 kg/ha





20–40 kg/ha

Milkfish/rearing phase Diammonium phosphate (18-46-0)

Milkfish/rearing phase NPK (14-14-14)

Shrimp/pond preparation Shrimp/rearing phase Milkfish/pond preparation Broadcast Milkfish/rearing phase broadcast

Urea (46-0-0)





Shrimp/pond preparation

5–120 kg/ha

10–100 kg/ha

Shrimp/rearing phase

3.2–5 kg/ha

4–5 kg/ha

25–200 kg/ha

40–150 kg/ha

12 kg/ha (every 15 days till harvest)

5–100 kg/ha

Shrimp/pond preparation

3–20 kg/ha



Shrimp/rearing phase

5–10 kg/ha



100–500 kg/ha

10–100 kg/ha

Milkfish/pond preparation Broadcast Milkfish/rearing phase broadcast Solophos (0-20-0) Ammonium sulfate (21-0-0) Calcium nitrate

Shrimp/pond preparation Shrimp/pond preparation (broadcast)

3–50 kg/ha



Shrimp/rearing phase (broadcast)

5–10 kg/ha



Source: Cruz-Lacierda, de La Pena, and Lumanlan-Mayo 2000; Cruz-Lacierda et al. 2008.

short environmental life and are relatively harmless, although they do affect water quality. Table 6 shows the application rates for some of these chemicals in pond preparation.

chemical agents are applied to kill fish and molluscs in the pond bottom. Table 7 shows some of the common piscicides and molluscicides in aquaculture ponds.

3.3  Practices to Improve Production 3.2.2  Application of Piscicides and Molluscicides Typical for pond preparation before stocking any commodity for culture is the eradication of other fish species and molluscs which may prey on the cultured species or compete for food, oxygen, and space in the culture environment. As a routine part of pond preparation,

3.3.1 Use of Hormones and Growth Promoters Exogenous hormones, particularly gonadotropins, have been used for years to induce final maturation of captive female broodfish. Hormone products such as luteinizing hormone releasing hormone-analog (LHRHa),

Approaches to Improve Fisheries Production

27

Table 5:  Summary of organic fertilizers used in milkfish and shrimp ponds and in polyculture of these two commodities Year

Organic Fertilizer

1996–1997

Chicken manure

Shrimp

500–3,000 kg/ha (pond preparation, broadcast

100–3,000 kg/ha (pond preparation; tea bags)

Polyculture —

200 kg/ha (rearing, tea bags)

100–1,000 kg/ha (rearing phase; tea bags)



Goat/pig manure

500–1,000 kg/ha (pond preparation, broadcast)





BioearthTM

500 kg/ha (pond preparation, broadcast)







100–500 kg/ha (pond preparation; tea bags)





100–200 kg/ha (rearing phase; tea bags)



Carabao manure



240–300 kg/ha (pond preparation; tea bags)





100–200 kg/ha (rearing phase, tea bag)



VIMACATM (Chicken/ pig manure)



1,000 kg/ha (pond preparation; tea bags)



1–10 tons/ha (pond preparation)



0.5–10 tons/ha (pond preparation)

0.1–1.5 tons/ha (rearing phase)





Cow/carabao manure

2.5 tons/ha (pond preparation)

50–250 kg/ha (pond preparation)



Mud press (sugar mill)

6 tons/ha (pond preparation)





Cow manure

2006–2007

Milkfish

Chicken manure

Horse manure Pig manure

16 kg/ha (pond preparation) —



1 ton/ha

Source: Cruz-Lacierda, de La Pena, and Lumanlan-Mayo 2000; Cruz Lacierda et al. 2008.

human chorionic gonadotropin (HCG), and other hormone containing products such as OvatideTM and OvaprimTM (both are a combination of gonadotropin and a dopamine antagonist). Hormones such as these

have been used in the Philippines for commodities such as milkfish, sea bass, bighead carp, catfish, groupers, and many other species (Kungvankij et al. 1986; Tan-Fermin and Emata 1993; Liao et al. 1979; Marte et

Table 6:  Use and dosage of other chemicals to modify soil or water quality for aquaculture of milkfish and shrimp and polyculture of the two species Year

Chemical

2006–2007

1996–1997

Milkfish

Shrimp

Polyculture

Agricultural lime (CaCO3)

0.2–6 tons/ha

1–10 tons/ha; 200–300 kg/ha (rearing phase)

1–5 tons/ha; 140–400 kg/ha (rearing phase)

Hydrated lime (Ca(OH)2)

0.2–2 tons/ha

0.4–2 tons/ha; 50–200 kg/ha (rearing phase)

0.75–1.5 tons/ha; 200–300 kg/ha (rearing phase)

Dolomite (MgCO3)

40–600 kg/ha

100–200 kg/ha/week

250 kg/ha

Agricultural lime

300–500 kg/ha





150–1,000 kg/ha





Hydrated lime

(Source: Cruz-Lacierda, de La Pena, and Lumanlan-Mayo 2000; Cruz Lacierda et al. 2008)

28

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Table 7:  Application of common piscicides and molluscicides in milkfish and shrimp culture and polyculture of these two commodities Year

Chemical (active ingredient)

2006–2007

Teaseed (saponin) Brestan 60 (triphenyltin acetate) Sodium cyanide Tobacco dust (nicotine)

Milkfish

Shrimps

Polyculture

10–50 kg/ha

1C–30 kg/ha

20–25 kg/ha

0.25–1.5 kg/ha



0.25–0.75 kg/ha

0.5–6 kg/ha



1–6 kg/ha

500–1,500 kg/ha

Thiodan (endosulfan)

1996–1997



0.1 ppm



0.1 ppm

D-crab (pyrethroid)



1 liter/ha



Clear 97 (trichlorfon)



20 kg/ha



5–400 kg/ha





Tobacco dust (nicotine)

400 kg/ha





Derris root (Rotenone)

300–800 kg/ha





Brestan (organotin)

250–600 kg/ha





0.1 ppm





Teaseed (saponin)

Gusathion

Source: Cruz-Lacierda, de La Pena, and Lumanlan-Mayo 2000; Cruz Lacierda et al. 2008.

Table 8:  Sample of hormone dosage used for induced spawning of the Asian catfish Clarias microcephalus and bighead carp Aristichthys nobilis Hormone

Catfish

Bighead Carp

HCG

4 IU/g body weight (BW)

2,000 IU/kg BW (female); 1,000 IU/kg BW (for male)

LHRHa

0.05 μg/g BW

20–50 μ g/kg BW (female); 10–25 μ g/kg BW (male)

OvaprimTM

0.5 μ L/g BW

0.5 ml/kg BW (female); 0.25 ml/kg BW (male)

OvatideTM

0.2 μ L/g BW

0.5 ml/kg BW (female); 0.25 ml/kg BW (male)

Source: Tan-Fermin et al. 2008; Gonzal et al. 2001. Note: OvaprimTM and OvatideTM are commercial preparations containing LHRHa and domperidone.

al. 1987; Fermin 1991; Almendras et al. 1988). Table 8 shows the dosage of various hormones used for induced breeding of catfish and bighead carp induced spawning. Another use of hormones in aquaculture is for sex reversal, either for masculinization or feminization. The culture of monosex fish has been shown to improve growth compared to mixed sex culture since a greater portion of energy in feed is channeled toward somatic

growth rather than reproduction (Chakraborty et al. 2011). The hormones 17-α-methyltestosterone (MT) and estradiol-17β are the most common hormones for masculinization and feminization, respectively (Pandian and Sheela 1995). In the Philippines, the most common species that undergo sex reversal through hormone treatment of MT are tilapia. Since the mid1980s commercial-scale sex reversal, mainly masculinization, through MT treatment has been practiced in many tilapia-producing countries including the Philippines (Popma and Green 1990). Diets are mixed with MT at 10 mg/kg at a rate of 15–20 percent of BW per day of tilapia for 20–30 days (Popma and Green 1990; Chakraborty et al. 2011). After this method, 97–100 percent phenotypically male tilapia can be achieved and ready for grow-out.

3.3.2  Use of Anesthetics Anesthetics are employed in fisheries and aquaculture in instances when the fish need to be transported or handled, which is stressful to the fish. Stress can result in immunosuppression, physical injury, and even death to the fish. During transport, anesthetics are used to

Approaches to Improve Fisheries Production

29

Table 9:  Common anesthetics and dosage used in common aquaculture species found in the Philippines Anesthetics

Common Carp

Nile Tilapia

Catfish

Milkfish

MS-222

100–250 mg/L a

100–200 mg/La





Benzocaine



2C–100 mg/L





Quinaldine

10–40 mg/L





a

2C–50 mg/L

a

a

2-Phenoxyethanol

400–600 mg/L

400–600 mg/L

0.75 mg/L (fingerlings); 0.5 ml/Lc (brood stock)

125 mg/Ld

Clove oil

40–100 mg/La













125 mg/Ld

a

Ethylene glycol

a

b

Note: a - Coyle, Durborow, and Tidwell 2004; b - Öğretmen and Gökçek 2013; c - Tan-Fermin et al. 2008; d - Reyes et al. 2015.

reduce metabolism which in turn reduces oxygen consumption and excretion rates (Coyle, Durborow, and Tidwell 2004; Strange and Shreck 1978). Immersion in anesthetic bath is the most common way anesthetics are applied to fish and crustaceans. For large-size fish, the anesthetic solution may be sprayed to the gills. The anesthetic is absorbed through the gills and enters the blood stream to take effect on the fish. Table 9 is a list of common anesthetics and their dosage for various aquaculture commodities. Environmental and human safety regulations on the use of anesthetics in aquaculture are not yet in place in the Philippines. In the United States, only

MS-222 is registered for use in food fish and requires a 21-day withdrawal period (Coyle, Durborow, and Tidwell 2004). Thus far, there is no such list of approved anesthetics for use in aquaculture in the Philippines.

3.4  Practices to Improve Aquatic Animal Health 3.4.1 Use of Antibiotics and Antimicrobials Antibiotics and antimicrobials are generally substances that kill or suppress the growth of microorganisms.

Table 10:  Antibiotic feed additives and their use and dosage as applied to shrimp culture Chemical Group (Commercial Product)

Pattern of Use

Amount Used

Chloramphenicol

DOC 1–30 days

3 g/kg feed

Disease control

2–2.5 g/kg feed

Tetracycline (OTC) Oxolinic acid

DOC 1–30

3 g/kg feed

Disease control, 3 times/day for 3–7 days

3 g/kg feed

DOC 12–60, 1-3 times/day Disease control, 1-3 times/day for 7 days

1 g/kg feed 0.2–4 g/kg feed

Furazolidone (Furazolidone, 98%)

DOC 1–100, 5 times/day

Furazolidone (PE-30)

Disease control 1–35, alternate with vitamin/wk, all feedings for 5–7 days

Furazolidone (PE-40)

Disease control, 2–3 times/d for 5–7 days

20 g/kg feed

Furazolidone (PE-60)

DOC 1–30, alternate with PE-30 4–5 times/day

20 g/kg feed

Source: Cruz-Lacierda, dela Pena, and Lumanlan-Mayo 2000. Note: DOC – days of culture.

1 g/kg feed 1–2.5 g/kg feed 20 g/kg feed

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

Antibiotics are substances produced by or derived from specific microorganisms and can destroy or inhibit the growth of pathogenic organisms and prevent or treat infection. The use of antibacterial treatment in aquaculture became widespread in the 1970s when bacterial pathogens became increasingly prevalent in aquaculture. However, antibacterial chemotherapy has been in practice for over 60 years, using sulphonamides to treat furunculosis in trout and tetracyclines against gram-negative pathogens (Inglis 2000). Method of dosing of these antibiotics may be through (a) immersion or water bath; (b) injection; (c) topical application; or (d) incorporation as a feed ingredient. The last is the more common approach particularly for shrimp culture. With the intensification of shrimp culture, fueled by its attractive price not only locally but more so in the international market, problems with shrimp diseases causing high mortalities need to be addressed to maintain production volume. Antibiotics and antimicrobial agents became the drug of choice to address disease problems.

3.4.2  Use of Chemotherapeutants As aquaculture operations intensified, disease occurrence from pathogenic organisms became a threat to production. These chemicals or drugs are selectively toxic to the causative agent of the disease. For instance, in shrimp culture, the prevalence of the luminous bacteria Vibrio has resulted in the devastation of many farms in the country, eventually resulting in the sharp decline in shrimp production not only in the Philippines but

40 30 20 10 0 2000s

Source: Cruz-Lacierda et al. 2008. Note: * Values in parenthesis are percentage of farms surveyed; n=number of farms surveyed.

50

1990s



1980s

5–20 ppm (10%)

1970s

Formalin

60

1960s

25–50 ppm (10%)

1950s

5–100 ppm (33%)

1940s

Calcium hypochlorite

1930s

Polyculture (n = 21)

1920s

Shrimp (n = 40)

1910s

Chemical

Figure 36:  Number of aquatic animal species introductions in the Philippines in the various decades

1900s

Table 11:  Disinfectants used in black tiger shrimp brackish-water farms in the Philippines in 2006–2008*

Number of Exotic Species Introduced with Records

30

Source: Cagauan 2007.

also in other shrimp-producing countries. To address the problem of Vibrio infection, it has become a practice to disinfect inflowing water in some shrimp farms. Chlorine (as calcium hypochlorite) or formalin is used to treat the water in reservoirs before use in the shrimp ponds (Cruz-Lacierda et al. 2008). Table 11 shows the dosage of disinfectants used in monoculture shrimp ponds and in polyculture with milkfish.

3.5  Practice to Diversity Cultured Commodities 3.5.1 Introduction of Exotic Aquatic Species New aquatic species from other countries are introduced to boost both capture fisheries and aquaculture production. Figure 36 shows the recorded number of introduced exotic species in the Philippines since the early 1900s. An estimated 45 percent of fish introductions are for aquaculture (food fish) purposes and 42 percent for the ornamental fish industry, 6 percent for recreational fishing, 6 percent for mosquito control (Guerrero 2014), and the remaining are probably incidental introductions

Approaches to Improve Fisheries Production

31

Table 12:  Partial list of invasive and potentially invasive introduced species to the Philippines Species

Origin

Reason for Introduction

South America

Ornamental

Channa striata (mudfish)

Malaysia

Culture

Channa micropeltes (Giant snakehead)

Thailand

Ornamental

Chitala (Clown knife fish)

Thailand

Ornamental

Chitala ornata (Clown featherback)

Thailand

Ornamental

Clarias batrachus

Thailand

Culture

Monopterus albus

Malaysia

Culture

Parachromis managuensis (Jaguar guapote)

Central America

Ornamental

Pterygoplichthys disjunctivus (vermiculated sailfin catfish)

South America

Ornamental

Pterygoplichthys pardalis (Amazon sailfin catfish)

South America

Ornamental

Pygocentrus nattereri (red-bellied piranha)

South America

Ornamental

Unknown

Ornamental

Arapaima gigas (Arapaima)

Sarotherodon melanotheron (black-chinned tilapia) Source: Guerrero 2014.

as ‘tag-along’ species. The peak of introduction of exotic fish species in the country was in the 1970s with more than 50 species introduced (Cagauan 2007). Introduction of exotic species is the second leading cause for the loss of biodiversity, after habitat destruction (Williams et al. 1989; IUCN 1999). Many fish species introduced for aquaculture have proven to be economically beneficial to many farming communities in the world, including the Philippines. Among the top freshwater species being farmed in the Philippines is an introduced species, the Nile tilapia Oreochromis niloticus. Although many countries consider the introduction of this species as a nuisance and consider the species to be invasive (Linde-Arias et al. 2008; Angienda et al. 2011), many more countries have accepted this species as an important aquaculture commodity. One of the early records of fish introduction to the Philippines was in 1915 with the release of common carp (Cyprinus carpio) from Hong Kong in Lake Lanao in Mindanao (Villaluz 1966; Escudero 1994). Fortunately, this species did not thrive well and is now considered nearly decimated in this lake. Another cyprinid which has grown in importance to freshwater aquaculture, especially in Laguna de Bay, is the bighead

carp, Aristichthys nobilis, introduced from Taiwan in 1968 (Guerrero 2014). Table 12 shows a list of some species introduced to the Philippines, either as food fish or for the ornamental fish industry, that have become invasive or have the potential to become invasive.

3.5.2  Translocation of Aquatic Species Even native fish species are not immune from being introduced to other bodies of water where they are not part of the native population. The translocation of native species from one drainage system to another in the same country is a widely accepted method for enhancement of many natural waters around the world (Innal and Erk’akan 2006). This may either be intentional or unintentional. Translocation may be a way of enhancing fisheries productivity. An example of intentional introduction is the case of milkfish Chanos chanos in Laguna de Bay for the fish pen culture industry. Milkfish is a marine species but with euryhaline characteristics that enable it to be cultured in a variety of aquatic environments, from marine cages to brackish-water ponds to freshwater fish pens (Bagarinao 1999). The commodity is continuously being produced in a wide

32

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

range of culture environments, including other lakes in the country, because this is a preferred food fish for Filipinos. Translocation may also be a method to conserve critically overexploited aquatic commodities, as in the case of the reef gastropod Trochus niloticus in the Philippines. This species’ population has dwindled due to

overfishing in the country’s reefs, not for food but for the production of mother-of-pearl buttons. It has been declared as a threatened species in the country. Encouraging results in the translocation of wild juveniles of Trochus niloticus into other sites proved to be a promising strategy for the conservation of this endangered species (Dolorosa, Grant, and Gill 2013).

4

PHYSICAL IMPACTS

4.1  Environmental Impacts 4.1.1 Loss of Ecosystem Services Due to Conversion of Mangroves to Aquaculture Ponds It is estimated that 50 percent of mangrove loss is attributable to its conversion to fishponds. Figure 37 illustrates the relationship between the loss of mangroves and the growth of brackish-water ponds in the Philippines until 1990. According to a review by Primavera (1995), the conversion of mangroves into ponds proceeded at a slow pace of about 760–1,200 ha/year up to 1940 since there

Figure 37:  The loss of mangrove areas and the development of brackish-water ponds in the Philippines Mangrove/Pond area (x 103 ha)

60 50 40 30 20 10

Culture Pond: Source: Primavera 1991; Primavera 1995.

Gov’t. – Leased

Privately – Owned

1990

1985

1980

1975

1970

1965

1960

1955

1950

1945

1940

1920

0

34

An Overview of Agricultural Pollution in the Philippines: The Fisheries Sector

was no active government support. Upon the creation of the BFAR in the late 1940s, funds for pond construction became available (mainly through international loans). Mangroves were considered ‘valueless land’ (as quoted from Carbin 1948 as cited by Primavera 1995) at that time and conversion to brackish-water milkfish pond was deemed a more useful alternative. Thus began the accelerated conversion of mangroves to brackish-water ponds at a rate of 5,000 ha/year in the 1950s and 1960s. Conversion slowed down to 800 ha/year in the 1970s when mangrove areas were placed under the joint jurisdiction of the fisheries and forestry bureaus and there was a move toward conservation. As the technology for shrimp culture developed, more mangroves were converted into ponds. The host of ecosystem services provided by mangroves which turned out to be far more valuable was left unaccounted for during the initial period of conversion into ponds. It was only with the establishment of set parameters for valuation of various ecosystem services that it now has become apparent that mangroves, left as is, have far more economic, environmental, and biological benefits than converting them to fishponds, and not the ‘valueless land’ they were deemed to be. Mangrove ecosystem-derived services include (a) interception of land-derived nutrients, pollutants, and suspended matter before these reach deeper water (Tam and Wong 1999); (b) export of materials that support nearshore food webs including shrimps (Sasekumar et al. 1992); (c) protection of vulnerable coastal areas from storm surges that have recently destroyed local communities in the country (Kathiresan and Rajendran 2005; Alongi 2008); (d) prevention of coastal erosion through sediment stabilization (Marshall 1994); and (e) nursery and spawning areas for a variety of commercially important fish, shellfish, and molluscs (Sasekumar et al. 1992). With the loss of mangroves, important subsidies to subsistence uses and ecological, economic, and conservation uses are also lost. It is interesting to note that the decrease in mangrove areas in various countries is inversely correlated with an increase in GDP but not generally correlated with population (Valiela, Bowen, and York 2001).

4.1.2  Eutrophication Eutrophication results from the heavy inputs of nutrients in the aquatic environment, mainly from unconsumed feeds, aquatic animal wastes, and other inputs into the aquatic system to boost production. A study on nitrogen and phosphorus utilization of formulated feeds under controlled laboratory conditions shows that an equivalent of only 33 percent of nitrogen and 29 percent of phosphorus is retained in fish (as biomass) and the rest is lost through fecal and urinary excretion (Cuvin-Aralar 2003). Since this was done in the laboratory, the feed ration was visibly consumed by the fish with some unquantified, but considered, minor nutrient losses through leaching. Feed conversion rates vary with species, feeding strategy, and feeding management. Overfeeding results in high feed conversion ratios (FCRs) with excess nutrients entering the culture environment as organic sediments or dissolved nutrients in the water column. Nitrogen and phosphorus loading rates from one ton of shrimp harvest have ranged from 10 to 117 kg of nitrogen and 9 to 46 kg of phosphorous, depending on FCR (White et al. 2008). Table 13 shows model estimates of amounts of nitrogen and phosphorus released to the aquatic environment from aquaculture as a function of FCR. David et al. (2009) documented the increasing nutrient flux in sediment cores from aquaculture activities in a number of marine aquaculture sites in the Philippines: Honda Bay and Malampaya Bay in Palawan, Table 13:  Estimated organic matter and nutrient loading for one ton of harvested shrimp released at different FCRs FCR

Organic matter kg/ton

Nitrogen kg/ton

Phosphorus kg/ton

1

500

26

13

1.5

875

56

21

2

1,250

87

28

2.5

1,625

117

38

Source: Asian Shrimp Culture Council 1993, as cited by White et al. 2008.

Physical Impacts

Table 14:  Comparison of phosphorus values from marine aquaculture sites in the Philippines Site

Characteristics

Malampaya Sound

Capture fisheries; shellfish culture

Honda Bay

Less aquaculture development

Manila Bay

39 km of fish cages

20–60

Bolinao Bay

1,100 fish cages (milkfish)

20–90

Milagros Bay

Developing aquaculture site; mainly shellfish

15–40

2

Baseline Value

P-range, ppm 15–85 22 (average)

15–20

Source: David et al. 2009.

Manila Bay, Bolinao in Pangasinan, and Milagros Bay in Masbate. The sites have varying degrees of aquaculture activity. Results show a narrow concentration range for nitrogen from older core samples when compared to newer ones. On the other hand, phosphorus showed significantly higher levels in younger or more recently deposited sediments. Sediments deposited years ago and older had 20 ppm phosphorous. On the other hand, a 2–3-fold increase in phosphorous levels was noted in sediments deposited within the last 15 years. Phosphorous sediment profiles reflected the intensity of aquaculture activities in the different sites. Honda Bay and Malampaya Sound in Palawan are sites where aquaculture activities had lower aquaculture intensity. Manila Bay has about 39 km2 of fish cages which are adjacent to urban centers. Bolinao has more than 1,100 fish cages, mainly milkfish (Chanos chanos), and Milagros Bay is a developing aquaculture site with shellfish as the major product. Phosphorous concentrations in these sites ranged from 10 to 90 ppm. Table 14 summarizes the phosphorous values obtained for the study sites. A study is currently being undertaken by the National Fisheries Research and Development Institute (NFRDI) on nutrient buildup from aquaculture ponds in the provinces of Bulacan, Bataan, Cavite, and Pampanga and the National Capital Region, all surrounding Manila Bay.

35

An indirect impact of eutrophication is mass fish kill. Mass fish kill is a common occurrence in aquaculture operations in the Philippines and has incurred huge financial losses for the aquaculture investor. In Laguna de Bay, 60 percent of mass fish mortalities recorded between the 1970s and the late 1990s were attributed to low dissolved oxygen, secondary to massive algal bloom due to eutrophication (Cuvin-Aralar 2001). The cause of massive algal bloom is excess nutrients in the lake, which in turn is due to eutrophication as has been discussed in the previous section. More recent incidents of mass fish kills in different regions of the country were also documented by the BFAR from 2005 to 2014 (Bantaya, pers.comm.). Of the more than 300 incidents of mass fish kills, almost 40 percent were because of poor water quality due to dissolved oxygen depletion and elevated ammonia. A number of instances of oxygen depletion were due to algal blooms. Interestingly, a few incidents of mass fish mortalities were also reported as being caused by agricultural pollution run-offs into inland waters with aquaculture activities. In Bolinao, Pangasinan, an important site for milkfish aquaculture, the site has experienced environmental changes due to these mariculture activities which release organic matter from unconsumed feed and fecal material that accumulate in the sediment. A massive fish kill incident in 2002 occurred in the area associated with the bloom of a dinoflagellate, accompanied by a

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