1. Estimation of ratio of fin weight to body weight of sharks in the eastern Pacific Ocean in 2006 Soon-Song Kim, Doo-Hae An, Dae-Yeon Moon and Seon Jae Hwang National Fisheries Research and Development Institute (NFRDI), Republic of Korea Soon-Song Kim, Doo-Hae An, Dae-Yeon Moon and Seon Jae Hwang National Fisheries Research and Development Institute (NFRDI), Republic of Korea

2. The survey area  9°13’S~1°36’N and 126°00’ ~138°21’W from September 20 to October 23, 2006  Korean longliner : 416 GRT  Monitoring : 28 set (one set per day)  No. of hooks used : 62,464 - each set : 2,240 (560 of each type)

3. Catch and species composition of shark species Shark species Number(%) Weight (kg) (%) Scientific nameEnglish name Alopias superciliosusBigeye thresher shark8320.13,15128.4 Lamna ditropisSalmon shark5914.32.04818.5 Prionace glaucaBlue shark4310.42,44222.0 Isurus oxyrinchusMako shark30.74704.2 Carcharhinus longimanusOceanic white-tip shark4811.68838.0 Sphyrna zygaenaSmooth hammerhead shark71.74944.5 Sphyrna lewini Scalloped hammerhead shark 143.478888.0 Pseudocarcharias kamoharaiCrocodile shark14234.46696.0 Scymnodon sqamulosis Smallmouth velvet dogfish shark 143.4480.4 Total41310011,093100

4. Shark species Bigeye thresher sharkSalmon shark Blue shark Longfin mako shark

5. Shark species Oceanic white-tip shark Smooth hammerhead shark Scalloped hammerhead shark Crocodile shark Smallmouth velvet dogfish

6. Catch per unit effort by bait Species (number) CPUE by bait (no./1,000 hooks) Chub mackerel SardineSquid Jack mackerel Milk fish Large-sized sharks (257)2.42.82.62.00.6 Small-sized sharks (156)2.6 2.82.21.4 Total(413)5.15.4 4.22.0

7. Fish condition at landing Species Number of individuals measured Fish condition at landing(%) AliveDeadPredation Bigeye thresher shark8377.122.9- Salmon shark1770.629.4- Blue shark2972.427.6- Mako shark366.633.4- Oceanic white-tip shark1163.636.4- Smooth hammerhead shark250.0 - Scalloped hammerhead shark20.0100.0- Crocodile shark13990.69.4- Smallmouth velvet dogfish shark1471.428.6- Total41377.522.5-

8. Disposal of sharks trunk Species Number of individuals measured Disposal rate (%) Release alive Discard Retain trunk after finning Discard trunk after finning Bigeye thresher shark830.010.80.089.2 Salmon shark591.713.676.38.4 Blue shark430.09.30.090.7 Mako shark3100.0 Oceanic white-tip shark480.016.712.570.8 Smooth hammerhead shark70.0 85.714.3 Scalloped hammerhead shark 140.021.464.314.3 Crocodile shark1420.797.91.40.0 Smallmouth velvet dogfish shark 1414.385.70.0

9. Disposal of sharks fin by fin type after fishing * 2 fishes larger than 1 meter were finned. LS: large-sized shark SS: small-sized shark ○ : Retain ×: Discard Species Fin type TrunkComment DorsalPectoralPelvicAnalCaudal Salmon shark ○○○○○ RetainLS Ocenic white-tip shark ○○○○○〃〃 Smooth hammerhead sharks ○○○○○〃〃 Mako shark ○○○○○〃〃 Blue shark ○○○○○ Discard 〃 Bigeye thresher shark ○○○○ × 〃〃 Crocodile shark*××××× 〃 SS Smallmouth velvet dogfish shark ××××× 〃〃

10. Sharks finning

11. Ratio of wetted fin weight to body round weight of shark Species Number of individuals measured Round weight (kg)(A) Wetted Fin weight (kg)(B) Ratio of B/A (%) Comments Bigeye thresher shark813,122116.33.7 Excluded caudal fin Salmon shark481,82694.25.2 Included caudal fin Blue shark452,593114.34.4 〃 Mako shark347019.44.1 〃 Salmon shark481,82694.25.2 〃 Ocenic white-tip shark 4584159.47.1 〃 Smooth hammerhead shark 749424.95.0 〃 Scalloped hammerhead shark 1383945.05.4 〃 Crocodile shark2524.28.1 〃 Total1637,115361.45.08 Excluded bigeye thresher shark

12. Order St. no. Number of individuals measured Wetted fin weight (kg) Dried fin weight (kg) Ratio (Dried/ Wetted) Number by species 112 22.412.20.54BS 2, BT 10 2131017.510.50.60BT 7, OW 1, SH 2 3142324.811.50.46BT 18, SS 3, OW 2 415611.77.00.60BT 2, BS 1, SS 1, OW 2 5161020.912.40.59BT 1, BS 3, SH 1, OW 4, CS 1 617714.810.30.70BS 5, OW 1, SS 1 71826.42.50.40BS 1, MS 1 81938.83.50,41OW 1, SH 1, SS 1 92048.73.30.38BS 3, BT 1 1021611.36.70.59BS 4, OW 1, SS 1 1122619.411.00.57OW 1, BS 2, SH 3 12231228.413.00.49BT 6, SH 1, SS 1, BS 3 132425.52.50.45BS 1, BT 1 Total102200.6106.40.53 BT 46, BS 25, SS 8, OW 13, SH 8, CS 1, MS 1 Ratio of wetted fin weight to dried weight of shark

13. Species Number of individuals measured Sex ratio (%) FemaleMaleUnidentified Bigeye thresher shark8458.331.010.7 Salmon shark5865.532.81.7 Blue shark4742.651.16.4 Mako shark3100.00.0 Ocenic white-tip shark4768.129.82.1 Smooth hammerhead shark742.957.10.0 Scalloped hammerhead shark1464.335.70.0 Crocodile shark14247.940.811.3 Smallmouth velvet dogfish shark harkdsharkshark 1478.614.37.1 Sex ratio of shark

14. Length distribution of sharks Species Number of individuals measured mean length (cm) Range (cm) Bigeye thresher shark8413899~196 Salmon shark6014044~186 Blue shark43191138~230 Mako shark3246.3196~330 Oceanic white-tip shark4811040~173 Smooth hammerhead shark7186.9144~211 Scalloped hammerhead shark14182.3140~212 Crocodile shark1428253~175 Smallmouth velvet dogfish shark1474.464~83

15. Results The catches of sharks taken on 62,464 hooks were 413 in number and 11,093kg in weight of 9 species The ratio of wetted fin weight to body round weight of sharks by species ranged from 4.1 to 8.1% and mean was 5.08%. The total ratio of wetted fin weight to dried fin weight of sharks and the ratio ranged 0.38 to 0.70 and mean value was 0.53. BW = DFW/[( Ratio of wetted fin weight to body round weight) x (Ratio of wetted fin weight to dried fin weight)]