2002/6/211 SWATT: Statistical Wizards Advisory & Training Team

2002/6/212 Specific Proposals

2002/6/213 A Specific Proposal By RAM Meta-analysis of species interactions and environmental and fishing change (link with H-MAP) Prediction of population and community trajectories based result of upon above project. –My comment: to clarify condition to require each complex model (make it simple as much as I can )

2002/6/214 Species Replacement of Pelagic Fishes Catch in Japan (1000 mt) Anchovy Horse mackerels Pacific saury Chub mackerel Sardine

2002/6/215 Cyclic Advantage Hypothesis The next dominant to sardine is anchovy – Yes! As I predicted The second next is chub mackerel Many people agree now Anchovy, Pacific saury, jack mackerel mackrel sardine Matsuda et al. (1992) Res. Pop. Ecol. 34:

2002/6/216 A mathematical model for cyclic advantage hypothesis dx/dt = c 1 +[r 1 (t)–2x – 4y – z]x dy/dt = c 2 +[r 2 (t)– x – 2y – 4z]y dz/dt = c 3 +[r 3 (t)–4x – y – 2z]z When y,z~0, x= r 1 /2, at which dy/dt>0 because r 2 -x>0 dz/dt<0 because r 3 -4x<0 Interior equilibrium is locally unstable A A A A B B B B C C C C

2002/6/217 “Community (multispecies) model is needed when either… Species interactions (prey-predator, …) probably affect stock dynamics and coexistence…, and like to understand why or to make a multispecies conservation or management plan. Trajectories of species are mutually (positively or negatively) correlated;

2002/6/218 Q&A Will western Pacific chub mackerel really recover? It depends on the fishing pressure

2002/6/219 Past recovery of chub mackerel Back to the 1950s

2002/6/2110 Large fluctuation of recruitment Strong year classes appeared twice

2002/6/2111 Immatures were caught before matured 1970s1980s1990s1993- %immatures 65.0%60.0%87.0%90.6%

2002/6/2112 Fishers missed chance of recovery Kawai,…,Matsuda, Fish. Sci. in press --Actual  F during s

2002/6/2113 Probability of stock recovery Kawai et al. in press 1990s is Japan’s “lost 10 years”.

2002/6/2114 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)

2002/6/2115 Difficulties & hopelessness in ecosystem modeling Indirect effects via the third species or adaptive change in traits is often counterintuitive and not negligible in the long-term effect (see Abrams, Polis…); We need many untested assumptions and intuitive understanding is difficult Indeterminacy (Yodzis 1988): Results (+/-) vary with small change in parameter values

2002/6/2116 Adaptive Management, or “Learning by Doing” If we change the management action (and already determine how to change it) with recent survey, the risk of mismanagement is much smaller; We try several actions in order to understand the ecosystem more detail; To learn the history of overfishing.

2002/6/2117 Guideline of ecosystem management To list up what data we continuously survey; To determine adaptive change in manage- ment action with the recent survey data; To examine a large variety of parameter values in the ecosystem model and to confirm robustness of the above adaptive management; To make falsifiable predictions

2002/6/2118 Target switching of multispecies fisheries (Katsukawa & Matsuda, Fish.Res. In press) Policy 1 (no switching; NSF) F i = f i /2(1+hx i ) Policy 2 (switching; SF) F i = f i x i /(  x i ) (1+hx i ) Fishers may focus on relatively abundant fish species.

2002/6/2119 Switching increases & stabilizes total catch, save it at low levels Switching No Switching (F=0.5) Switching

2002/6/2120 Is SBT monotonically recovering? Mori et al. Pop.Ecol Stock size #Matures (million) #Immatures (10million) #Total (10 million)

2002/6/2121 Inertia of over-fished age-structure Inverse Baby-boom effect We must publish this before stock stops increasing.

2002/6/2122 Age (Size) structured model is needed when… Fluctuation in Recruitment is large (Tuljapurkar 1988) Fishing pressure is dramatically changed (Mori, Katsukawa, Matsuda 2001 Pop.Ecol. 43: ) The age at first capture is changed The age at maturity is changed

2002/6/2123 One of our Goals Research to contribute on Biodirvesity Conservation and Sustainable Use As by Convention on Biological Diversity –States are responsible for conserving their biological diversity and for using their biological resources in a sustainable manner These are 2 of the 3 WWF missions