Management actions for protecting and recovering wild salmon populations in Japan. Masahide Kaeriyama Hokkaido University

Transcription

1 Management actions for protecting and recovering wild salmon populations in Japan. Masahide Kaeriyama Hokkaido University

2 Return (millions) Annual change in return of chum salmon in Japan during Hokkai do Honsh u Year Recent Return Decrease trend in Honshu since the late 199s, and in Hokkaido since the early 2s

3 Million fish Production trend of Pacific salmon Synchronizing with the climate regime shift PINK CHUM SOCKEYE CHINOOK COHO Annual change in catches of Pacific salmon in the North Pacific Ocean / / / / Year

4 Ln (Catch, 1 6 ) Us =.33t (R² =.97) Chum 6 Canada Ca = -.76t Japan (R² =.2525*) 5 Russia USA Us= -.27t (R² =.3) Canada Japan Russia USA Pink Ca = -.694t (R² =.1161) Ja = -.65t (R 2 =.39) Ru =.311t (R² =.1689) Ru =.352t (R² =.2278*) Ja = -.376t (R² =.2629*) Year Annual change in catch of chum and pink salmon in the North Pacific in Chum salmon Canada Decrease Japan Decrease? Russia Increase USA Stable? Pink salmon Canada Decrease Japan Decrease Russia Increase USA Stable? (by NPAFC Database) Southern populations: Decrease Russian populations: Increase

5 K (million fish) ALPI Temporal changes in ALPI and carrying capacity (K) of three species (sockeye, chum, and pink salmon) K ALPI R 2 =.868, (F=462, P<.1, n=72) Salmon carrying capacity significantly synchronized with the long-term climate change Year class Pink 5 Chum Carrying capacity trend Pink: decrease Chum: stable? Sockeye: decrease

6 Run size by Sep. (thousands) Mean SST isothermal diagrams around Japan in September 29: W 21: S 1989: W 199: W 1991: S 1992: W 1993: W 1994: S 1995: W 1996: S 1997: W Tsushima Warm Current S: Strong, W: Weak 1998: W 1999: S 2: S 21: W 22: W 23: W 24: W 25: S 26: S 27: S 28: S 29: W 21: S 211: S 212: S Annual change in the run size of early-population chum salmon returning to the Japan Sea coast in Hokkaido. 5, Weak: 2,47±1,28 thousands (N=14) Strong: 1,478±785 thousands (N=1) 4, (ANOVA: F=4.314, P<.5) 3, 2, 1, Year

7 Abundance (million fish) Annual changes in abundance of wild/hatchery salmon Chum Wild Hatchery 1 5 Wild Hatchery Hatchery Salmon Effects Pink % Hatchery/Biomass Hatchery salmon Pink <2% Chum < 6% Sockeye <1% 2 Wild Sockeye Wild Year 2 1 Pink Chum Sockeye Year

8 Southeast Alaskan Chum Salmon (Andrew W. Piston 211)

9 Wild salmon rivers have occupied about 3% in Hokkaido Locations of survey sites for detecting natural reproduction of chum salmon in Hokkaido in 28 and 29 (Miyakoshi et al. 212).

10 Age FL (mm) Carrying capacity and density-dependent effect of chum salmon RCC=(CC-B)/CC 1 RCC: Residual Carrying Capacity CC: Carrying Capacity B: Biomass FL: Fork length (mm) AGE: Mean age at maturity Hokkaido chum salmon r=.979 (F=753.8, P<.1) 67 This result suggests that carrying capacity of chum salmon is closely related not only with the long-term climate change, but also the density-dependent effect, the density-dependent growth will also affect breeding characters (e.g., body size and RCC (%) fecundity) of the wild salmon RCC (%) r=.879 (F=19.1, P<.1) RCC (%)

11 Genetic Influence of Hatchery Salmon Escapement Genetic differentiation of Yurappu River chum salmon Variable nucleotide sites in the 481 bp 5 portion of mtdna control region Pairwise population Fst estimated between chum salmon populations CHI YP Yurappu River Oct. (YPO) TOK NIS Chitose R. (CHI) CHI TOK NIS YPO YPN YPD CHI. TOK.. NIS YPO...3. YPN *.13. YPD.211**.16**.486**.168**.59**. *P<.5 **P<.1 Yurappu River chum salmon remains a native stock in the late-run, but is intermingled with populations introduced from other rivers by the artificial hatchery program. Mixed population Endemic population Nov. (YPN) Tokachi R. (TOK) Genetic Disturban ce Transplanted Endemi c Dec. (YPD) Nishibetsu R. (NIS) Early Spawning time Late

12 Genetic Influence of Hatchery Salmon (2) Tedori R. Haplotype Hp-1 Hp-2 Unrooted tree based on genetic distance between haplotypes Hp-3 Hp-4 Hp-5 Tedori River received a massive seed-transplantation of chum salmon from the Chitose Salmon Hatchery during 198s and 199s. Tedori River chum salmon were closely related with Chitose and Tokachi River populations, and did not show the genetic differentiation with Tokoro River population, despite no-seed- transplantation from this river in Hokkaido. This result shows that a part of Tedori River chum salmon receive gene flow and disturbance following the seed transplantation from not only Chitose River, but also other rive populations in Hokkaido. Fig. 2. Haplotype distribution of chum salmon populations in the Tedori and Gakko rivers. Fig.3. Haplotype distribution of chum salmon populations in Japan/ (modified from Sato et al. 21)

13 Total number of juvenile Total number of juvenile chum salmon (millions) Genetic-disturbance for Japanese chum salmon Chitose Salmon Hatchery Chitose Salmon Hatchery (CSH) play a role of a center of salmon hatchery program and main base of salmon seed transplantation in Japan. Chitose River chum salmon population extremely decreased and could not reproduce by 196s because of the overfishing. The CSH released a lot of juvenile transported from almost all populations around Hokkaido during 196s and 198s. So, the massive seed transplantation from the CSH caused that almost all early-run populations were genetically disturbed in Japan since the 198s. A B Native Non native Western Pacific Eastern Pacific Nemuro A. Total number of both native and non-native juvenile chum salmon released into the Chitose River. B. Total number of juveniles transplanted from each region and released into the Chitose River.

14 Hatchery salmon Mixed population Casket of Genetic Resources

15 Index of health and benefits of global ocean (Halpern et al Nature 11397)

16 Index of health and benefits of Pacific salmon Interaction between wild and hatchery salmon Carrying capacity Freshwater Ocean Freshwater Coastal Waters Ocean breeding competition, straying densiity-dependnt growth spawning area productivity climate change, productivity Ecosystem protection Biodiversity Fisheries activity Freshwater Coastal water Ocean Habitats Species Genetic Coastal fishery Hatchery activity habitat loss, artificial river, channelization, urbanization artificial coastline, overfishing overfishing overfishing replacement by hatchery juvenile

17 Conceptual Diagram on the Sustainable Adaptive- Management of Pacific Salmon in Japan Feedback control Monitoring - Climate change - Biological information (body size, age composition, breeding & genetic characters - Condition of river ecosystem, etc. Action plan (& Modeling) - Conservation: Natural freshwater ecosystems - Protection: wild salmon - Sustainable hatchery program

18 Sustainability for ocean ecosystem conservation and seafood security Will we be able to use the ocean organisms as seafood in the future? We should recognize to live in the earth ex dono ecosystem service, and know natural threats Carrying capacity in the marine ecosystem More than enough is too much Fisheries Industry : Economic efficiency Ecosystem Approach What do we need for seafood security and marine ecosystem sustainability in present and future? Education - Paradigm shift from the traditional fisheries science to the new ecological fisheries science - Dietary education 食育 e.g. local production for local consumption 地産地消 How do we establish the sustainable fisheries and aquaculture management based on the ecosystem approach? Risk Management: Adaptive management & Precautionary principle 1) Adaptive learning: Learning by doing, Responsibility of risk exposition 2) Feedback control: Monitoring, Modeling - Fisheries: Long-term climate change (e.g., Global warming, Regime shift), Carrying capacity - Aquaculture: Food security, Conservation of marine ecosystem, Water pollution