BackgroundAtlantic Salmon (Salmo salar) is an anadromous migratory species adapted to cool temperatures. It is protected by the Bern convention and by the European Habitats Directive. It has been listed as vulnerable by the French IUCN Red List. Salmon decline is the result of combined and cumulated, mainly anthropic, causes: climate change, increasingly high number of impoundments, degradation of water quality and habitat and over-exploitation by fisheries. Monitoring of this species has been carried out on three rivers in France (Southern part of the distribution area) to produce data and knowledge (growth, precocious maturity, survival) for stock management.For 24 years, a specific and standardised electric fishing protocol has been used to target young-of-the-year (0+ parr) Atlantic salmon. Sampling was restricted to areas with shallow running water that flows over a coarse bottom substrate, i.e. the preferred habitat of young salmon. This monitoring and inventory of growing areas thus allows assessment of juvenile recruitment and provides baseline data required to calculate total allowable catches (TACs).New informationThe dataset currently consists of 47,077 occurrence data points from 105 sites spanning up to 24 years in three different watersheds in France. Beyond our project, this dataset has a clear utility to research since it associates abundance measurements with the measurement of biological traits and the collection of tissue samples. It allows for current and retrospective characterisation of individuals or populations, according to life history traits and genetic features in relation to changes in environmental conditions. The fact that the monitoring takes place in France, the southern part of the distribution area, over 24 years, makes the dataset particularly relevant for climate change studies.

This note extends analyses by Burrell and Swinbank & Peters on the consequences of imposing a siphon on a market for quotas. A siphon is a tax in kind levied on exchanged quota licences so as to generate rights which could be transferred to some specific producers and new entrants. A framework based on a micro-economic model of producer behaviour in a tradable quota regime is developed to derive supply and demand functions forleased quota rights at the industry level. The three schemes for the siphon defined by Burrell are further examined in terms of price, quantity and welfare effects. The model is applied to the case of milk quotas in France on the basis of a sample of dairy farmers for the year 1991.

L'Organisation commune de marché de la banane dans l'Union européenne : impact de la taille du contingent tarifaire appliqué aux bananes dollar et non traditionnelles ACP par Hervé Guyomard, Nadine Herrard, Catherine Laroche et Chantai Le Mouël Le 1er Juillet 1993, l'Union européenne (UE) a finalement instauré un marché commun de la banane. L'Organisation commune de marché (OCM) mise en place remplace un ensemble de politiques nationales complexes et hétérogènes, incompatibles avec le Marché Unique. La nouvelle réglementation repose essentiellement sur i) la fixation d'un contingent tarifaire dans l'UE pour les bananes d'Amérique latine et non traditionnelles ACP (Afrique, Caraïbes et Pacifique), et ii) le concept de partenariat entre le commerce de bananes communautaires et traditionnelles ACP d'une part, et le commerce de bananes d'Amérique latine d'autre part. L'objet de cet article est double. Il s'agit en premier lieu de proposer un cadre simplifié d'analyse du fonctionnement du marché mondial de la banane en régime d'OCM dans l'UE. Il s'agit en second lieu d'analyser la sensibilité des équilibres de marché à la taille du contingent tarifaire imposé par l'UE aux bananes d'Amérique latine et non traditionnelles ACP sur la base de simulations réalisées à l'aide d'un modèle d'équilibre partiel du marché mondial de la banane.