Mekong giant catfish tracking project (MCTP) Japan-Thai cooperative study Mekong giant catfish tracking project (MCTP) Nobuaki Arai, Kyoto University Hiromichi Mitamura, Kyoto University Yasushi Mitsunaga, Kinki University Thavee Viputhanumas, DOF, Thailand 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Contents Background Objectives Materials and Methods Results & Discussion Conclusions The Golden Triangle 11/18/2018 5th Fish Telemetry in Europe

What’s Mekong giant catfish? The Mekong giant catfish, Pangasianodon gigas is one of largest freshwater fish in the world. TL 3 m and BW 300 kg. It is endemic to the Mekong River 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Endangered species EN in the IUCN Red list Appendix I of CITES 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Objectives To investigate spawning and after spawning behaviors. To investigate young catfishes behaviors. No information about young catfish yet. To evaluate effectiveness on the catfish resource enhancement In the Mekong River and reservoirs. 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Study areas Mekong River Thailand Chiang Khong Nakohn Phanom Kalasin Song Khram river Study area in 2002 20° 10° 100° 110° The Mekong River in Thai territory The Mae-puem Reservoir Khong Chiam 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe The Mekong River Lao PDR Thailand 11/18/2018 5th Fish Telemetry in Europe

Ultrasonic biotelemetry VR1 and VR2 receiver system detects signals from the coded transmitters and stores their IDs and the time. Coded ultrasonic transmitters encode 256 IDs at the same ultrasonic frequency. 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Coded transmitters 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Internal attachment 11/18/2018 5th Fish Telemetry in Europe

Characteristics of the Mekong giant catfish* used in 2002 and 2003 Mekong River 　 2003 　Mekong River 　Mae-puem ID FL(cm) BW(kg) TL(cm) 1 103.5 15.0 31 81.0 4.3 42 108 13.0 2 86.5 9.0 32 76.5 3.5 43 103 13.5 3 105.0 17.0 33 83.0 4.6 44 116 14.8 4 91.0 12.0 34 81.5 4.1 45 17.6 5 35 88.5 5.8 46 120 18.8 6 67.5 4.2 36 80.5 47 113 16.2 7 67.0 4.7 37 4.4 49 110 17.2 8 72.0 5.2 38 79.0 3.8 50 111 14.2 9 69.0 5.4 39 4.5 - 10 70.5 40 78.5 Average 83.6 9.3 81.1 112.1 15.7 SD 5.0 3.2 0.6 5.3 2.1 11/18/2018 5th Fish Telemetry in Europe *All the catfish were artificially inseminated.

5th Fish Telemetry in Europe VR1 setup locations in 2002 Bannakhae No.1 60km Ban Chaiburi No.4 No.3 No.5 Song Khram river Release point We used five VR1 receiver systems. We set up these receivers at these areas along Mekong River. Two receivers was set up near the release point. One was set up at a branch. Another was set up at the 60 km upstream point. Last one was set up at the 40 km downstream point. 50km River View Hotel No.2 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe VR1 setup locations in 2003 100° 110° 20° Chiang Khong Nong Khai Nakohn Phanom Thailand Khong Chiam 10° 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Mae-puem Reservoir 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe ④ ⑥ ⑤ ⑧ ⑦ ⑨ ⑩ ⑪ ⑫ ⑬ ⑭ X Release station ① ③ ② VR2 setup in the Mae-puem Reservoir Local fishermen 11/18/2018 5th Fish Telemetry in Europe

VR2 in the Mae-puem reservoir VR2 receiver 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Release 27th June of 2002 in the Mekong River 11th May of 2003 in the Mekong River 20th May of 2003 in the Mae-puem Reservoir 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe 11/18/2018 5th Fish Telemetry in Europe

Tracking by a speed boat Lao PDR 600m We also tracked the catfish on board just after the release. Thailand 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Results & discussion 2002 ID FL(cm) BW (kg) 27 28 29 30 1 2 3 4 5 6 Up/Dn 104 15.0 R.P. 60 km up ↑ 87 9.0 ? 105 17.2 91 12.0 68 4.2 Branch 60 km up 7 67 4.7 8 72 5.2 9 69 5.4 50km down ↓ 10 71 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Bannakhae No.1 60km Five of ten catfish were well tracked for ten days. Four of ten went upward about 60km. Speed: 178cm/s One went downward about 50km. Ban Chaiburi No.4 No.3 No.5 Song Khram river 50km River View Hotel No.2 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe 2003 100° 110° 20° Chiang Khong Nong Khai 200km Nakohn Phanom Thailand Khong Chiam Two catfish were caught by fishermen on 19th May of 2003. About 200km upward from the release point. They swam 200km only for a week. 10° 11/18/2018 5th Fish Telemetry in Europe

In the Mae-puem Reservoir ④ ⑥ ⑤ ⑧ ⑦ ⑨ ⑩ ⑪ ⑫ ⑬ ⑭ X Release station ① ③ ② First download was performed on 26th May of 2003 a week after the release. All the catfish were recorded. 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe All the IDs were detected at St.1. ID42 inhabited around St.3 or 4 but swam almost everywhere except around St.14. Night time ID42 showed clearly diurnal periodicity. 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Conclusions We tracked the catfish using coded ultrasonic transmitters and VR1 & 2 receivers in the Mekong River and the Mae-puem Reservoir. The catfish had a tendency toward upward. The behavior indicated diurnal rhythm. They seemed to be nocturnal in their habits. 11/18/2018 5th Fish Telemetry in Europe

5th Fish Telemetry in Europe Thanks ! 11/18/2018 5th Fish Telemetry in Europe