At the 1996 World Fisheries Congress, Donald A. McCaughran declared seventyfive years of regulatory success for the International Pacific Halibut Commission. The Commission's mandate was to reverse the precipitous decline in halibut stocks that had become apparent in the 1910's, and save this fishery from economic extinction. The biologists and fishermen who sat on the Commission assumed that the appropriate biological target was the one that yielded the maximum sustainable harvest. Using a bioeconomic model of the fishery and regression analysis, I argue the Commission's use of global quotas to achieve its biological goal of maximum sustained yield was most certainly an economic failure. I also argue its policies were very likely a biological failure, as well. While arguably accomplishing its biological goal of the maximum sustainable yield in 1960, dynamic bioeconomic theory indicates their policies probably destabilized the biological fishery. The paper will first sketch the historical background of the industry. Then the regulatory history will be discussed. Then the economic literature will be reviewed as it applies to the Pacific halibut industry. Finally, the historical data will be examined and the proposition that the regulatory management of the halibut fishery was a success will be tested. The period 1928 to 1960 is covered as it provides both reliable data and a continuous period of regulation, at the end of which the biological goal of maximum sustainable yields was apparently achieved. In conclusion, I find that statistically the fishermen were insensitive to the direct effects of the quota and the total quantity of fish available, and instead responded to the quota's indirect effects on the fishermen's costs, which induced the inflow of greater fishing capital than otherwise would have occurred.

No description available.

The focus of this thesis has been on the identification of the primary conditions that attract or deter multilateral interventions into internal conflicts in the Asia Pacific region. This thesis develops a framework which is applied to four cases of internal conflict to see what roles twenty-two structural and perceptual conditions have played in determining why multilateral intervention was initiated in two of the cases, and why multilateral intervention failed to be initiated in the other two cases. The research found that multilateral organizations will accept risks and costs associated with intervention if certain structural and perceptual conditions make intervention an attractive option. These conditions are, a favourable or significant international environment or international event(s), the consent of a sovereign state (even if it is induced), sustained and critical regional and international media coverage, a complete collapse of the state in conflict tainting it with the term 'failed state', a high probability of success, potential economic benefits, a humanitarian crisis (in respect of Unregulated Population Movements and genocide/politicide), the possibility of a clear exit strategy, and a self-interested Member State who can greatly subsidize an intervention. Multilateral non-interventions, on the contrary, are driven by a combination of a lack of sustained and critically analyzed media coverage on conflict issues and consequences, generally positive tactics and strategies adopted by disputants, conflicts of a long duration, the international environment, economic factors unfavourable to intervention, resistance levels to intervention or a failure to call for intervention, lack of any clear exit points, and an escalation phase. The importance of these conditions suggest that multilateral organizations are reluctant to take risks and costs when political will, for the collective and self, are not provoked. Consequently, particular structural and perceptual conditions trigger or influence political will. The analysis of four case studies (East Timor, Solomon Islands, Philippines (Moros), and West Papua) concludes that multilateral interventions will be the exception to the rule in the foreseeable future given the obvious selection bias evident in these policies, and the project questions the ad hoc determinants of current multilateral intervention policies.

The aim of this thesis is to provide an overview of the health of Pacific Islands young people in New Zealand, with a particular emphasis on the effects of their dietary and lifestyle behaviours upon long-term health. This research is based on the observation that noncommunicable, or life-style, diseases are the leading causes of morbidity and mortality for Pacific Islands people in New Zealand, that these diseases are invariably attributable to dietary and lifestyle habits, and that these habits become instilled during the adolescent period. Three main methods were undertaken to achieve this aim. The first constituted a review of literature concerning the health of Pacific Islands people in New Zealand, including a discussion of what health means to Pacific Islands people, along with the main health issues that this population encounters. The importance of food to Pacific Islands people is also considered in this review, along with the influence of diet on Pacific Islands people's disease patterns. Existing studies concerning the dietary habits of Pacific Islands youth are also detailed. The second stage of the research involved conducting research into the health of Pacific Islands young people in Christchurch, based in part on the methodology and findings of these previous studies. As the thesis will show, while Christchurch has the fourth largest Pacific Islands population in New Zealand, this population is considerably smaller than those in other main centres. This means that Pacific Islands people have less health resources and services available to them. This research revealed that Pacific Islands young people in Christchurch, and in New Zealand in general, consume a diet that is high in fat and low in other nutrients. Research into the health of Pacific Islands young people is deemed necessary to help to counter the high incidence of lifestyle related diseases in the adult population. Further, by identifying potential health outlooks for the future generation of Pacific Islands adults, research in Christchurch will be useful in ensuring that services and resources to meet Pacific Islands people's specific health needs.

No description available.

The first part of this thesis is an assessment of the ability of global climate models to reproduce observed features of the leading Empirical Orthogonal Function (EOF) mode of North Pacific sea surface temperature (SST) anomalies known as the Pacific Decadal Oscillation (PDO). The simulations from 13 global climate models I am analyzing were performed under phase 3 of the coupled model intercomparison project (CMIP3). In particular, I am investigating whether these climate models capture tropical influences on the PDO, and the influences of the PDO on North American surface temperature and precipitation. My results are that 1) the models as group produce a realistic pattern of the PDO. The simulated variance of the PDO index is overestimated by roughly 30%. 2) The tropical influence on North Pacific SSTs is biased systematically in these models. The simulated response to El Niño-Southern Oscillation (ENSO) forcing is delayed compared to the observed response. This tendency is consistent with model biases toward deeper oceanic mixed layers in winter and spring and weaker air-sea feedbacks in the winter half-year. Model biases in mixed layer depths and air-sea feedbacks are also associated with a model mean ENSO-related signal in the North Pacific whose amplitude is overestimated by roughly 30%. Finally, model power spectra of the PDO signal and its ENSO-forced component are “redder” than observed due to errors originating in the tropics and extratropics. 3) The models are quite successful at capturing the influence of both the tropical Pacific related and the extratropical part of the PDO on North American surface temperature. 4) The models capture some of the influence of the PDO on North American precipitation mainly due to its tropical Pacific related part. In the second part of this thesis, I investigate the ability of one such coupled ocean- atmosphere climate model, carefully initialized with observations, to dynamically predict the future evolution of the PDO on seasonal to decadal time scales. I am using forecasts produced by the Canadian climate data assimilation and prediction system employing the Canadian climate model CanCM3 for seasonal (CHFP2) and CanCM4 for decadal (DHFP1) predictions. The skill of this system in predicting the future evolution of the PDO index is then inferred from a set of historical “forecasts” called hindcasts. In this manner, hindcasts are issued over the past 30 years (seasonal), or over the past 50 years (decadal) when they can be verified against the observed historical evolution of the PDO index. I find that 1) CHFP2 is successful at predicting the PDO at the seasonal time scale measured by mean-square skill score and correlation skill. Weather “noise” unpredictable at the seasonal time scale generated by substantial North Pacific storm track activity that coincides with a shallow oceanic mixed layer in May and June appear to pose a prediction barrier for the PDO. PDO skill therefore depends on the start season of the forecast. PDO skill also varies as a function of the target month. Variations in North Pacific storminess appear to impact PDO skill by means of a lagged response of the ocean mixed layer to weather “noise”. In CHFP2, times of increasing North Pacific storm track activity are followed by times of reduced PDO skill, while the North Pacific midwinter suppression of storm track activity with decreasing storminess is followed by a substantial recovery in PDO skill. 2) This system is capable of forecasting the leading 14 EOF modes of North Pacific SST departures, that explain roughly three quarters of the total SST variance. CHFP2 is less successful at predicting North Pacific SSTs, i.e., the combination of all the EOF modes, at the seasonal time scale. 3) Besides the skill in Pacific SST, CHFP2 skillfully predicts indices that measure the atmospheric circulation regime over the North Pacific and North America such as the Pacific/North American pattern (PNA) (skillful for three out of four start seasons) and the North Pacific index (NPI) (skillful for all four start seasons). 4) CHFP2 is successful at forecasting part of the influence of Pacific SST on North American climate at the seasonal time scale. Measured by 12-month average anomaly correlation skill, in this system the PDO is a better predictor for North American precipitation (skillful for all four start seasons) than temperature (skillful for one out of four start seasons). In CHFP2, ENSO is a better predictor for North American temperature (skillful for all four start seasons) than the PDO. Both ENSO and the PDO are, however, good predictors for North American precipitation (skillful for all four start seasons). Finally, DHFP1 is less successful at forecasting the PDO at the decadal time scale. Ten-year forecasts of the PDO index exhibit significantly positive correlation skill exclusively in the first year of the forecast. When the correlation skill of the predicted index averaged over lead years is considered, the PDO skill in this system stays significantly positive during the first three years of the decadal forecast. In other words, this climate data assimilation and prediction system is expected to skillfully predict the future three year averaged evolution of the PDO index, but not the evolution of the index in each year individually. / Graduate

This thesis aims to investigate the stresses at mid-ocean ridge offsets, and particularly at the particular class of offsets represented by oceanic microplates. Amongthese, the Easter microplate is one of the best surveyed. This thesis first studies the stress field associated with mid-ocean ridges and simple types of ridge offsets, and then uses the stress field observed at Easter to constrain the driving mechanism of microplates. Two-dimensional finite element modelling is used to predict the lithospheric stress indicators, which are then compared with observations. Extensional structures at high angles (> 35 ) to ridge trends are often observed at ridge-transform intersections and non-tranform offsets, but remained unexplained until now. This study proposes that the topographic loading created by the elevation of mid-ocean ridges relative to old seafloor is a source of ridge parallel tensile stresses, and shows they can be explained by the rotation of ridge parallel tensile stresses at locked offsets. The elasto-plastic rheology is used to investigate the evolution of normal faults near mid-ocean ridges. It is shown that variations in the lithospheric strength, caused entirely by variations in the brittle layer thickness, can account for the observed variations in fault character with spreading rate and along-axis position. Plasticity is shown to prevent the achievement of large fault throws in thin brittle layers. Consequently, it may be important at fast spreading ridges. A new dynamic model is proposed for Easter microplate. It mainly consists of: 1) driving forces along the East and West Rifts, resulting from the combination of a regional tensile stress with an increasing ridge strength towards rift tips, 2) mantle basal drag resisting the microplate rotation, and contributing with less than 20% to the total resisting torque, and 3) resisting forces along the northern and southern boundaries. To explain both the earthquake focal mechanism evidence and theexistence of compressional ridges in the Nazca plate, the boundary conditions alongthe northern boundary are required to change with time, from completely locked tolocked in the normal direction only. This study does not invalidate the microplate kinematic model proposed by Schouten et al. (1993), but shows that normal resisting forces along the northern and southern boundaries of Easter microplate must exist in order to explain the stress observations. Also, it suggests that ridge strength variations play an important role in the dyamics of mid-ocean ridge overlap regions.

The northern Lau Basin contains the northeastern-most part of the Tonga arc-basin system. Volcanic rocks associated with the recent-arc have been sampled from Tafahi and Niuatoputapu, and young basalts «1.5Ma) have been dredged from Northern Lau Spreading Centre (NLSC), the northeastern limb of the King's Triple Junction. The 1982 'Kallisto' cruise dredged two ophiolite sections, one containing boninitic, and the other tholeiitic, lavas, from the inner wall of the northern Tonga trench. The magma genesis of these lava suites is related to the structural and geochemical controls imposed during the tectonic evolution of the region. The geochemical controls result from processes related to the mantle dynamics in the northern Lau Basin, and to along-trench variations and the degree of influence of the subduction component. The lavas associated with the Central Lau Spreading Centre are derived from the Lau Basin mantle reservoir, which has Indian MORB mantle (!MM) isotopic characteristics. This reservoir has been present under the region since early-arc magmatism, as indicated by the trace elements and !MM isotopic signatures of the tholeiitic lavas from the eastern ophiolite section, and Eocene lavas from 'Eua. A reservoir with the geochemical characteristics of residual Samoan plume mantle underlies the northern Lau Basin. This mantle has been influxing through the rip in the Pacific plate, at the northern termination of the Tonga trench, since the Lau Basin began to open « 6Ma), as a result of processes relating to subduction roll-back. The north Tongan boninites, the lavas from Tafahi and Niuatoputapu have residual plume mantle sources. However, prior to the opening of the Lau Basin, the proto-Tonga trench formed a barrier to this influx, and therefore, the influence of the plume cannot be detected in lavas associated with the early-arc, such as the tholeiites from one of the ophiolite sections and the Eocene lavas from 'Bua. The variations in the trace element and Pb isotopic compositions of the lavas from the Northern Lau Spreading Centre indicate that mixing has occurred between Lau Basin and residual plume mantle end-members in the central northern Lau Basin. The residual plume mantle sources of the north Tongan boninites and the lavas from Tafahi, Niuatoputapu and the Tofua arc have been enriched by a subduction component, the characteristics of which are enrichment in Lll..E, Ph ± LREE. In the south, the subduction component is made up of fluids derived from subducted Pacific altered oceanic crust and pelagic sediments. However, in the north, it is comprised predominantly of fluids derived from Pacific volcanogenic sediments, with a contribution from altered oceanic crust and possibly subducted plume crust.

Cryoprotection in stabilized mince from Pacific whiting (Merluccius productus) was investigated by monitoring changes in physical and chemical properties during 32 weeks of frozen storage. The effects of 4 different cryoprotectants were evaluated by torsion test, color analysis, extractability of salt soluble proteins, and formation of dimethylamine (DMA) and 2-thiobarbituric acid (TBA). The quality of the stabilized mince was significantly higher than the control (mince without cryoprotectants) when compared by shear strain, salt soluble proteins, and DMA. The results show that the functionality of the proteins in the mince can be protected by using cryoprotectants with Polydextrose® being the most effective of the 4 tested. The effect of food-grade protease inhibitors on the gel-forming characteristics of Pacific whiting mince was also investigated. Four levels (1, 2, 3, and 4%) of different protease inhibitors (beef plasma protein, whey protein concentrate, egg white liquid, and egg white powder) were added to the stabilized mince before heating and effects on texture and color were evaluated. Shear strain was significantly increased by increasing the level of inhibitors. Beef plasma protein was most effective and presented significantly higher strain than the other inhibitors tested. Due to higher concentration of proteolytic enzymes in the mince, an increased amount of protease inhibitors is needed compared to surimi to prevent proteolysis during heating. / Graduation date: 1995

Cathepsin B was the most active cysteine proteinase in the Pacific whiting (Merluccius productus) fish fillet, and cathepsin L in surimi when the activities of the most active cysteine proteinases (cathepsin L, B, and H) were compared. Cathepsin L showed maximum activity at 55°C in both fish fillet and surimi, indicating its function in myosin degradation during conventional cooking of fish fillet and surimi. Washing during surimi processing removed cathepsin B and H but not cathepsin L. Autolytic analysis of surimi proteins showed that the myosin was the primary target, while actin and myosin light chain showed limited hydrolysis during 2 hr incubation. When purified Pacific whiting proteinase was incubated with various component of fish muscle, proteinase was capable of hydrolyzing purified myofibrils myosin, and native and heat-denatured collagen. The degradation pattern of myofibrils by the proteinase was the same as the autolytic pattern of surimi. Inhibition by the food-grade proteinase inhibitors varied with the catalytic type of proteinase. Beef plasma protein (BPP) had a higher percentage of papain inhibitors, followed by whey protein concentrate (WPC), potato powder (PP), and egg white (EW). On the other hand, EW had a higher percentage of trypsin inhibitors followed by BPP, PP, and WPC. EW inhibited trypsin activity completely at levels as low as 1%. WPC inhibited the autolytic activity of fresh surimi. Bovine serum albumin (BSA) was not effective as WPC. WPC can be used as an inhibitor for the Pacific whiting surimi, but high concentration is required. A limited number of inhibitory components were found, as the components in food-grade inhibitors were characterized by inhibitory activity staining. Both EW and PP showed more serine proteinase inhibitors than cysteine proteinase inhibitors. PP showed one cysteine inhibitory component while EW did not show any. BSA in both WPC and BPP acts as an nonspecific competitive inhibitor and reduces the enzyme activity. An unidentified high molecular weight protein (HMP) found in WPC, BPP, and BSA functions as an alternative substrate for papain while it functions as true inhibitor for trypsin. / Graduation date: 1995