We investigate the relative weights of catch plans, expected profit, and traditions in fishers' decision-making for five New Zealand fleets subject to an individual transferable quota (ITQ) management regime. Métiers were defined for these fleets as a combination of gears, management units, and a targeting index (either target species or statistical area). A nested logit random utility model was used to model the métier allocation of fishing effort in relation to catch plans, expected profit, and past fishing allocations. This study showed that traditions and catch plans appeared to be important determinants of fishers' behavior for these New Zealand fleets. The model developed in this study fitted the data generally well and was also able to predict, in most cases, future effort allocation both one month and one year ahead.Résumé: Nous étudions le poids relatif des portefeuilles de captures, du profit attendu et des traditions dans le processus de prise de décision des pêcheurs, dans le cas de six flottilles néozélandaises gérées par des quotas individuels transférables (ITQ). Plusieurs métiers ont été définis pour ces flottilles, en utilisant une combinaison des engins de pêche, des unitès de gestion et d'un indice de ciblage (soit les espèces recherchées ou les régions statistiques). Un modèle de choix discrets imbriqué (« random utility model ») a été utilisé pour modéliser l'allocation de l'effort de pêche en métiers, en utilisant les plans de pêche, le profit attendu et les allocations de pêche passées comme variables explicatives. Nous montrons que les traditions et les plans de pêche sont d'importants déterminants du comportement de pêche dans le cas des flottilles néo-zélandaises étudiées. Le modèle développé dans cette étude est bien calibré par les données disponibles et peut permettre dans la plupart des cas de prévoir raisonnablement quelle sera l'allocation de l'effort de pêche un mois, et même un an à l'avance.

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-This review aims at comparing the fisheries management systems existing in New Zealand and in the European Union. The involvement of stakeholders at all stages of the management process is generally more transparent and better established in New Zealand than in the EU. Both systems aim at achieving an adequate balance between sustainability and utilisation and consider the precautionary approach as a founding principle. The social objectives are probably more explicit in the EU management system. In New Zealand, B MSY is a legal management target for all stocks in the quota management system (QMS), but management strategies were poorly explicit until most recently. In the EU, there have not been any legal management targets or strategies until 1999. Since 1999, a number of multi-annual recovery and management plans have been established, including both management targets and strategies. Both management systems include conservation and access regulation measures. The EU management measures aim at regulating fisheries outputs and inputs, and discarding is tolerated. New Zealand management is almost exclusively output-based, and discarding practices are banned. In the EU, while individual quotas (IQs) are implicit in several countries, there is no consistent pattern across Member States for allocating TACs. In New Zealand, individual transferable quotas (ITQs) are implemented, and some flexibility in catch-quota balancing is provided by a carry-over allowance and the payment of a landing tax, the deemed value, for every fish landed above quota. If rights-based management were introduced in the EU based on, e.g., the New Zealand model, we suggest that concentration rules be set in accordance with the social objectives of the Common Fisheries Policy, and also that the deemed value should be set based on science and economics.

We evaluated alternative management strategies for the Otago and Southland rock lobster (Jasus edwardsii) fisheries in New Zealand. We compare a number of decision-rule-based management strategies and assess amalgamation of the two separate quota management areas that currently comprise the fishery. The analysis combines a spatial sex- and length-structured simulation model of the fishery with an economic module that converts catches and effort into revenues and costs. We compare performance of alternative management strategies using a variety of biological and economic performance indicators relevant to a range of management objectives identified by stakeholders. The results demonstrate the importance of modelling economic performance, since the relative performance of different management strategies differ when considering catch versus net revenues. The analysis also reveals important distributional issues, since some strategies that increase the overall value of the fishery create both winners and losers.

-Managing adequately the exploitation of commercial species subject to technical interactions is a key step towards the ecosystem approach to fisheries. We evaluate here, using a bio-economic modelling approach building on the ISIS-Fish simulation platform, the relative impact of total allowable commercial catches (TACC) and of taxes applicable to over-quota landings (deemed value) on the sustainability of a selection of species exploited by the New Zealand hoki (Macruronus novaezelandiae) fishery. We investigate some aspects of the hoki mixed fisheries, consisting of four fleets and nineteen métiers, by considering the technical interactions between hoki and Southern hake (Merluccius australis). The dynamics of effort allocation were modelled using gravity model, using value per unit of effort (VPUE) as attractivity coefficient. Several management scenarios, based on different levels of TACC, effort limits and deemed value have been defined. The impact of these strategies on spawning biomass and catches has been investigated. The results confirm that the deemed value may, in combination with TACC, be an efficient management tool. By increasing the hoki deemed value, we could somehow limit the decrease in the hoki TACC needed to harvest Western hoki sustainably. Constraining hoki fishing also restricts Southern hake fishing in the Chatham Rise and in the West Coast South Island, but leads to increased targeting of this species in the Sub-Antarctic area. The relative costs of renting/buying quota or paying the deemed value are most constraining when the hoki TACC is at relatively low level and when the hoki deemed value is more than 1.5 times the current value.Key words: Fleet dynamics / New Zealand hoki fishery / Deemed value / Fisheries management Résumé -La gestion adéquate de l'exploitation d'espèces commerciales sujettes à des interactions techniques constitue un premier pas dans la direction de l'approche écosystémique des pêches. Nous évaluons ici, au moyen d'une approche de modélisation bio-économique s'appuyant sur la plate-forme de simulation ISIS-Fish, l'impact relatif du total admissible de captures commerciales (TACC) et de taxes appliquées aux débarquements « hors quota » (taxes sur leur valeur estimée), sur la conservation d'une sélection d'espèces exploitées par la pêcherie de hoki (Macruronus novaezelandiae) néo-zélandaise. Nous étudions certains aspects de la pêcherie mixte de hoki, représentée par quatre flottilles et dix-neuf métiers, en considérant les interactions techniques entre le hoki et le merlu austral (Merluccius australis). La dynamique de l'allocation de l'effort de pêche a été modélisée en utilisant un modèle de gravité, dans lequel la valeur par unité d'effort (VPUE) représente le coefficient d'attractivité. On a défini plusieurs scénarios de gestion, basés sur différents niveaux de TACC, de limitation d'effort de pêche et de la taxe. L'impact de ces stratégies sur la biomasse féconde et les captures a été étudié. Les résultats confirment que la taxe, combinée avec les TA...