Tonle Sap Fisheries: A Case Study on Floodplain Gillnet Fisheries

Table of Contents

by

Dirk Lamberts

RAP Publication 2001/11

ASIA-PACIFIC FISHERY COMMISSION
Food and Agriculture Organization of the United Nations
Regional Office for Asia and the Pacific
Bangkok, Thailand

The designations employed and the presentations of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Opinions expressed in this publication are those of the author and do not imply any opinion whatsoever on the part of FAO.

NOTICE OF COPYRIGHT

All rights reserved. This publication may not be reproduced, in whole or in part, by any method or process, without the written permission from the copyright holder. Applications for such permission with a statement of the purpose and extent of the reproduction desired should be addressed to the Senior Fishery Officer, FAO Regional Office for Asia and the Pacific, Maliwan Mansion, 39 Phra Athit Road, Bangkok 10200, Thailand.

© FAO 2001

Table of Contents

PREFACE

PREPARATION OF THIS DOCUMENT

ABBREVIATIONS & ACRONYMS

ACKNOWLEDGMENTS

INTRODUCTION

Cambodia - some relevant facts
Cambodia and inland fisheries

i. Fish production and consumption
ii. Contribution of inland fisheries to the national economy
iii. Fish production and food security

Objectives of the study
Methodology

i. Study area and characterization of the habitats
ii. Identification of habitat types by macrophyte vegetation and flood regime
iii. Selection and location of the sampling areas and sites
iv. Sampling procedure

PART I. TONLE SAP ECOSYSTEM

The physical environment

i. Climate
ii. Geography
iii. Hydrology

Biotic components of the ecosystem
Productivity of the ecosystem and natural resource use

i. Ecosystem productivity
ii. Natural resource use in the Tonle Sap ecosystem

Limnological parameters: methods
Results of the limnological sampling

i. Diurnal changes in water quality
ii. Seasonal changes in water quality

Discussion: floodplain habitats ecology

i. Diurnal changes and patterns
ii. Seasonal changes and patterns - phases of flooding

PART II. TONLE SAP FISHERIES

Catches
Fishing techniques and gear

i. Large-scale fisheries (fishing lots)
ii. Medium-scale fisheries
iii. Subsistence (small-scale) fisheries

Fisheries management
Environmental aspects

PART III. GILLNET FISHERIES: CASE STUDY

Methods

i. Experimental gillnet fishing
ii. Additional fish sampling
iii. Selected species
iv. Fish identifications
v. Ichthyological parameters

Results

i. Composition of the gillnet catches
ii. Selectivity of gillnets - comparison of experimental gillnet catches with those by other types of gear
iii. Habitat-related results of the experimental gillnet fishing

Discussion: floodplain gillnet fisheries
Selected data and information on eight species of economic importance

i. Cirrhinus microlepis (Sauvage, 1878)
ii. Cyclocheilichthys apogon (Valenciennes, 1842)
iii. Cyclocheilichthys enoplos (Bleeker, 1850)
iv. Henicorhynchus siamensis (deBeaufort, 1927)
v. Osteochilus melanopleurus (Bleeker, 1852)
vi. Paralaubuca typus (Bleeker, 1865)
vii. Trichogaster microlepis (Günther, 1861)
viii. Trichogaster trichopterus (Pallas, 1770)

PART IV. TONLE SAP AQUACULTURE

Description of Tonle Sap aquaculture systems
Environmental aspects
National policies, strategies, plans and programmes for Tonle Sap aquaculture development

ANNEXES

ANNEX 1. Macrophyte species composition of the case study habitats
ANNEX 2. Fish species encountered in the case study
ANNEX 3 .Summary overview of sampling activities

REFERENCES