4 May Can we say goodbye to the MSY theory and a pessimistic view of the state of the world fisheries? FAO suggested that the total world landings do not increase any more. The Maximum Sustainable Yield theory always guarantees the stock persistence; The adaptive management is one of the best ways against uncertain ecosystems. Anonymous straw man says

4 May Can we say goodbye to the MSY theory and a pessimistic view of the state of the world fisheries? FAO suggested that the total world landings do not increase any more. The Maximum Sustainable Yield theory always guarantees the stock persistence; The adaptive management is one of the best ways against uncertain ecosystems. I say the adaptive management sometimes results in undesired outcomes; I say the MSY theory does not guarantee coexistence of species = food web constraint; 4WFC organizer gave us the title of “getting more fish and reconciling fisheries with conservation”;

4 May Today’s my talk We can get more fish sustainably; MSY theory does not guarantee biodiversity; Adaptive management is dangerous; Recommendations

4 May Can the world catch not really increase? Species base statistics

4 May Landings of demersal marine fish has not grown since 1970s （ FAO1996)

4 May Landings of small pelagic fish is still increasing with fluctuation anchoveta sardine chub mackerel Atlantic herring

4 May Fig. 1. Global trends of mean trophic level of fisheries landings, 1950 to 1994 Pauly et al. (Science1998:279:860;) Fishing Down– Is this bad? Marine areas inland areas Peruvian anchovy increased mean trophic level Catch of lower trophic levels is a smaller impact. Decrease of mean trophic level in environment is bad.

4 May I often eat lower trophic level fish, but should eat more. 650 yen (US$6) with coffee

4 May Whales consume fish more than human (Tamura & Ohsumi 1997)

4 May “Initial” and recent biomass of whales Source: SeaWorld web site except minke whales (F. Kasamatsu, book in Japanese)

4 May Nothern Pacific minke whales eat anchovy.

4 May Two phenotypes of whales-fisheries competition idea By Japan Gov. Whales destroy the ocean. “...in a complicated food web structure, indirect effects of culling top predator (whales) on abundance of target fish is either positive or negative,...” By Yodzis 2001 Trend Ecol Evol Fisheries destroy the ocean.

4 May Who is more familiar with environment? Rich or poor nations? Analysis of Ecological footprint （ source WWF 2002) EFP World2.28 High Income6.48 Intermediate1.99 Low income0.83 EFP Afganistan0.95 Iraq1.38 Israel4.44 Germany4.71 Japan4.77 Canada8.84 USA9.70 EFP: global ha/person

4 May My comments on whale-fisheries competition Top predators eat fish more than human –We can get more fish if top predators decrease Top predators have decreased. Whales eat anchovy, do not directly compete with human or fisheries. We must consider reconciling with conservation

4 May Pelagic fish stock is unstable -- species replacement -- Catch in Japan (1000 mt) Anchovy Horse mackerels Pacific saury Chub mackerel Sardine Matsuda & Katsukawa 2002 Fish Oceangr

4 May Cyclic Advantage Hypothesis Matsuda et al. (1992) Res. Pop. Ecol. 34: The next dominant to sardine is anchovy – -- Yes! As I predicted in The second next is chub mackerel -- Many people agree now Anchovy, Pacific saury, jack mackerel mackrel sardine

4 May Why did sardine stock collapse in 1990s? Natural fluctuation (Watanabe et al CJFAS ) –Failure of recruitments (getting older) –Fallacy of critical period theory –We can get more sardine in 1980s, more anchovy and Pacific saury now. At low stock level, fishing pressure may prevent from recovering...

4 May Q&A Q: Will western Pacific chub mackerel really recover? A: It depends on the fishing pressure

4 May Large fluctuation of recruitment in Northeastern Pacific chub mackerel Strong year classes appeared twice Kawai et al Fish Sci

4 May Strong year classes were caught before the age at maturity 1970s1980s1990s1993- %immatures 65.0%60.0%87.0%90.6% Kawai et al Fish Sci

4 May Fishers missed chance of recovery Kawai,…,Matsuda, Fish. Sci F during s actual stock abundance (million tons)

4 May Probability of stock recovery Kawai,…,Matsuda 2002 Fish Sci The decade of 1990s was “Japan’s lost 10 years” Probability of stock recovery

4 May Future of Pelagic Fish Populations in the north-western Pacific: If overfishing of immatures continues, –Chub mackerel will not recover forever; If cyclic replacement hypothesis is true, –Sardine will not recover forever; Do not catch immatures too much –The overfishing is an experiment for my hypothesis. (Adaptive mismanagement)

4 May Today’s my talk We can get more fish sustainably; MSY theory does not guarantee biodiversity; Adaptive management is dangerous; Recommendations

4 May Requiem to Maximum Sustainable Yield Theory Ecosystems are uncertain, non- equilibrium and complex. MSY theory ignores all the three. Does MSY theory guarantee species persistence? - No!! Stock abundance surplus production

4 May Kyoto Declaration and Plan of Action on the Sustainable Contribution of Fisheries to Food Security in 1992 (FAO) Article 14 “When and where appropriate, consider harvesting multiple trophic levels in a manner consistent with sustainable development of these resources”.

4 May Examples of biological community at MSY (Matsuda & Abrams in review) (b) (a) 12 5 (c) Solution maximizing total yield from community MSY solution often reduces species and links; (d) (e)

4 May Examples of biological community at MSY (Matsuda & Abrams in review) (b) (a) 12 5 (c) 100%92%61%12%6% exploit more species, more trophic levels (d) (e) Constrained MSY that guarantee coexistence

4 May Conclusion of story 2 MSY theory does not guarantee species coexistence Fisheries must take care of biodiversity conservation explicitly = Foodweb constraint to reconciling fisheries with conservation

4 May Today’s my talk We can get more fish sustainably; MSY theory does not guarantee biodiversity; Adaptive management is dangerous; Recommendations

4 May Feedback control in fishing effort is powerful... A straw man says; Even though the MSY level is unknown, the feedback control stabilizes a broad range of target stock level. Stock size N f(N) N*N*N*N*N*N*

4 May Feedback control with community interactions also result in undesired outcomes. (M & A in preparation) r = (0.454,1.059,1.186,0.247,-0.006,-0.028,-0.059,-0.704,-0.308,-0.238) A = (a ji ) = e 9 = 0.1, e i =

4 May Feedback control may result in extinction of other species (sp. 6). de 9 /dt = u(N 9 -N 9 *) ratio

4 May Conclusion of story 3 Single stock monitoring is dangerous Target stock level is much more sensitive than we have considered in single stock models. We must monitor not only stock level of target species, but also the “entire” ecosystem.

4 May Today’s my talk We can get more fish sustainably; MSY theory does not guarantee biodiversity; Adaptive management is dangerous; Recommendations

4 May Recommendations #1 1.Do fishing down in food items!! Eat small pelagic fishes 2.We can eat more fish, not use as fish meal!! 3.Reduce discards before and after landings (our dishes); 4.Establish food market of temporally fluctuating fishes at lower trophic levels 5.Improve technology for effective use of lower trophic levels (Japan Soc. of Fisheries) Seafoods)

4 May Recommendations #2 1. Switch a target fish for sp. replacement (Matsuda & Katsukawa 2002 Fish. Oceanogr) 2. Monitor the ecosystems 3. Conserve immatures; 4. Improve technology for selective fishing 5. Conserve both fishes and fisheries; 6. Say goodbye to MSY reference points;

4 May I express sincere thanks to The organizers for comfortable hospitality, especially Yvonne Sadovy; The audience who chose this session; I apologize that –I must confess that I said as the straw man said; –my English is very awk; –I looked for positive answer for the session title