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Vermard, Youen; Rivot, Etienne; Mahevas, Stephanie; Marchal, Paul; Gascuel, Didier. |
Recent advances in technologies have lead to a vast influx of data on movements, based on discrete recorded position of animals or fishing boats, opening new horizons for future analyses. However, most of the potential interest of tracking data depends on the ability to develop suitable modelling strategies to analyze trajectories from discrete recorded positions. A serious modelling challenge is to infer the evolution of the true position and the associated spatio-temporal distribution of behavioural states using discrete, error-prone and incomplete observations. In this paper, a Bayesian Hierarchical Model (HBM) using Hidden Markov Process (HMP) is proposed as a template for analyzing fishing boats trajectories based on data available from... |
Tipo: Text |
Palavras-chave: Bayesian Hierarchical Models; Hidden Markov Model; State-space model; VMS; Fleet behaviour; Fishing effort. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00009/11993/9342.pdf |
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Vermard, Youen. |
In the current context of fisheries management, simulation models are required to support the evaluation of management scenarios. These models should include the key processes of the fishery system: stock dynamics, fleet dynamics, manager decision-making, and the interactions between these three elements. Most of the existing models have concentrated on the modeling of biological processes, population dynamics, and ecosystem interactions. However, a number of fisheries management failures could have resulted from a misunderstanding of fishers behavior rather than from limited knowledge of the status of fishery resources. It has for example been showed that in an exploited system, fishers’ spatial behavior influences the predicted outcomes of management... |
Tipo: Text |
Palavras-chave: Dynamique de flottille; RUM; VMS; Évaluation de mesures de gestion; Fleet dynamics; Random Utility Model; VMS; Management strategy evaluation. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00001/11256/7799.pdf |
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Dransfeld, Leonie; Gerritsen, Hans D.; Hareide, Nils R.; Lorance, Pascal. |
With slow growth rates, late maturity and a high maximum age of 100 years or more, orange roughy can be classified as a vulnerable deepwater fish species that can only sustain low rates of exploitation. Historical patterns of exploitation associated with this species suggest that it is currently not possible to manage its fisheries in the Northeast Atlantic sustainably, and the total allowable catch for orange roughy has been gradually reduced to zero for European fisheries since 2010. Orange roughy to the west of Ireland and Britain occurs on distinct bathymetric features (seamounts, hills and canyons) as well as on flat ground along the continental slope. Productivity-susceptibility analysis (PSA) was performed to evaluate the biological vulnerability of... |
Tipo: Text |
Palavras-chave: Ecological risk assessment; VMS; Continental slope; Beryciformes; Atlantic Ocean. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00176/28758/27234.pdf |
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