PRESENCE, DISTRIBUTION, MIGRATION PATTERNS AND BREEDING SITES OF THIRTY FISH SPECIES IN THE AYEYARWADY SYSTEM IN MYANMAR WIN KO KO2, ZI ZA WAH2, Norberto ESTEPA3, OUCH Kithya1 SARAY Samadee1, KHIN MYAT NWE2, Xavier TEZZO1, Eric BARAN1 1 WorldFish 2 Myanmar Department of Fisheries, 3 Consultant TABLE OF CONTENTS 1 INTRODUCTION ............................................................................................................................... 1 2 METHODOLOGY .............................................................................................................................. 1 2.1 Approach ................................................................................................................................. 1 2.2 Area studied ............................................................................................................................ 2 2.1 Surveys of fishermen .............................................................................................................. 3 2.1 Species selection ..................................................................................................................... 3 2.2 Data analysis ........................................................................................................................... 7 2.3 Ecological value of townships ................................................................................................. 8 2.3.1 Number of species breeding by township ............................................................................. 8 2.3.2 Importance of species to fisheries ......................................................................................... 8 2.3.3 Surface area of fish breeding sites by township .................................................................... 9 2.3.4 Ecological value from a fishery perspective ........................................................................... 9 2.4 LIMITATIONS AND POSSIBLE BIASES OF THE STUDY ............................................................. 10 2.4.1 Self-assessment of yield ....................................................................................................... 10 2.4.2 Variable fishing effort .......................................................................................................... 10 3 RESULTS......................................................................................................................................... 11 3.1 Species whose migratory status is unknown ........................................................................ 11 3.2 Overview of migration and breeding in the Ayeyarwady system ......................................... 11 3.3 Species by zone and habitat type ......................................................................................... 15 3.4 Seasonal abundance of fish surveyed ................................................................................... 15 3.5 Timing of catches .................................................................................................................. 17 3.6 Species and number of breeding sites .................................................................................. 17 3.7 Breeding sites in townships .................................................................................................. 17 3.8 Ecological value of townships in fisheries ............................................................................. 19 4 CONCLUSION ................................................................................................................................. 21 5 BIBLIOGRAPHY .............................................................................................................................. 22 6 ANNEX 1: MONTHLY DISTRIBUTION OF YIELDS ............................................................................ 25 7 ANNEX 2: DETAILS BY MIGRATORY SPECIES SURVEYED ............................................................... 27 7.1 Migratory species with no known breeding sites ................................................................. 27 Hilsa kelee ..................................................................................................................................... 27 Ilisha megaloptera ........................................................................................................................ 29 7.2 Non-migratory species with breeding sites .......................................................................... 30 Bagarius bagarius ......................................................................................................................... 30 Cirrhinus mrigala ........................................................................................................................... 31 Gudusia variegata ......................................................................................................................... 32 Hemibagrus microphthalmus ........................................................................................................ 33 Pangasianodon gigas .................................................................................................................... 34 Sperata aor .................................................................................................................................... 35 7.3 Migratory species with breeding sites .................................................................................. 36 Catla catla ..................................................................................................................................... 36 Cirrhinus cirrhosus ......................................................................................................................... 41 Labeo calbasu................................................................................................................................ 46 Lates calcarifer .............................................................................................................................. 49 Pangasius conchophilus ................................................................................................................ 52 Pangasius pangasius ..................................................................................................................... 57 Rita rita ......................................................................................................................................... 62 Silonia silondia .............................................................................................................................. 67 Wallago attu ................................................................................................................................. 70 EXECUTIVE SUMMARY Our study of the presence, distribution, migration patterns and breeding sites of thirty fish species in the Ayeyarwady system is based on a systematic sampling of traditional ecological knowledge. More than 200 fishers were interviewed in 42 sites belonging to 37 townships in the delta and the Central Dry Zone. Thirty species were selected for surveys, in addition to hilsa, which was dealt with in a separate companion report. This selection was based on a combination of criteria covering commercial importance, migratory status in other countries, and critically endangered status for some species. The migratory status of fourteen fish species out of 30 is not known to fishermen. These species are: Anguilla anguilla and Anguilla bicolor (caught but not abundant), Anodontostoma chacunda, Bagarius yarrelli, Chaca burmensis, Macrognathus zebrinus, Pangasianodon hypophthalmus, Pangasius larnaudii, Raiamas guttatus, Tenualosa toli and Pristis microdon (rare species). The migratory status is also unknown for Cyclocheilichthys apogon, Mastacembelus armatus and Monopterus cuchia, although these species are not particularly rare. For the other species, average monthly catch per fisherman is much higher in the delta than in the Central Dry Zone. The five migratory species dominant in catches are Pangasius conchophilus, Tenualosa ilisha, Rita rita, Pangasius pangasius and Hemibagrus microphthalmus. Three out of five are catfishes. These top-five species are followed by species that are not abundant but remain common, in particular during their migration period: Wallago attu, Cirrhinus cirrhosus/mrigala, Bagarius bagarius, Catla catla, Labeo calbasu, Sperata aor, and Silonia silondia. The remaining species (Gudusia variegata, Lates calcarifer, Bagarius yarrelli, Hilsa kelee, Ilisha megaloptera, Macrognathus zebrinus, Pangasianodon hypophthalmus and Mastacembelus armatus) are rare in catches. The monthly abundance patterns of these species are detailed in the report. Among these species, two are considered to be migratory with no known breeding sites (Hilsa kelee and Ilisha megaloptera). Six species are considered non-migratory, but their breeding sites in the Ayeyarwady system are known (Bagarius bagarius, Cirrhinus mrigala, Gudusia variegata, Hemibagrus microphthalmus, Pangasianodon gigas, Sperata aor). Last, there are nine migratory species whose breeding sites are also known (Catla catla, Cirrhinus cirrhosus, Labeo calbasu; Lates calcarifer; Pangasius conchophilus; Pangasius pangasius; Rita rita; Silonia silondia; Wallago attu). We map in the report all the breeding areas described by fishers for these species. The present study also features an analysis of zones based