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| Registros recuperados: 51 | |
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| Bourdaud, Pierre; Travers-trolet, Morgane; Vermard, Youen; Cormon, Xochitl; Marchal, Paul. |
| The objective of this study is to analyse at fine scale the annual, seasonal and spatial distributions of several species in the Eastern English Channel (EEC). On the one hand, data obtained from scientific surveys are not available all year through, but are considered to provide consistent yearly and spatially resolved abundance indices. On the other hand, on-board commercial data do cover the whole year, but generally provide a biased perception of stock abundance. The combination of scientific and commercial catches per unit of effort (CPUEs), standardized using a delta-generalized linear model, allowed to infer spatial and monthly dynamics of fish distributions in the EEC, which could be compared with previous knowledge on their life cycles.... |
| Tipo: Text |
Palavras-chave: Commercial data; Eastern English Channel; Seasonality; Spatial distribution; Survey data. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00387/49805/50385.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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| Pinto, Cecilia; Travers-trolet, Morgane; Macdonald, Jed; Rivot, Etienne; Vermard, Youen. |
| The biological status of many commercially-exploited fishes remains unknown, mostly due to a lack of data necessary for their assessment. Investigating the spatio-temporal dynamics of such species can lead to new insights into population processes, and foster a path towards improved spatial management decisions. Here, we focused on striped red mullet (Mullus surmuletus), a widespread, yet data-limited species of high commercial importance. Aiming to quantify range dynamics in this data-poor scenario, we combined fishery-dependent and -independent datasets through a series of Bayesian mixed-effects models designed to capture monthly and seasonal occurrence patterns near the species’ northern range limit across 20 years. Combining multiple datasets allowed... |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00460/57187/59150.pdf |
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| Ulrich, Clara; Reeves, Stuart A.; Vermard, Youen; Holmes, Steven J.; Vanhee, Willy. |
| Single-species management is a cause of discarding in mixed fisheries, because individual management objectives may not be consistent with each other and the species are caught simultaneously in relatively unselective fishing operations. As such, the total allowable catch (TAC) of one species may be exhausted before the TAC of another, leading to catches of valuable fish that cannot be landed legally. This important issue is, however, usually not quantified and not accounted for in traditional management advice. A simple approach using traditional catch and effort information was developed, estimating catch potentials for distinct fleets (groups of vessels) and metiers (type of activity), and hence quantifying the risks of over-and underquota utilization... |
| Tipo: Text |
Palavras-chave: Advice; Demersal; Effort; Fcube; Mixed fisheries; North Sea; TACs. |
| Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00044/15491/12970.pdf |
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| Girardin, Raphael; Hamon, Katell; Pinnegar, John; Poos, Jan Jaap; Thebaud, Olivier; Tidd, Alex; Vermard, Youen; Marchal, Paul. |
| Anticipating fisher behaviour is necessary for successful fisheries management. Of the different concepts that have been developed to understand individual fisher behaviour, random utility models (RUMs) have attracted considerable attention in the past three decades, and more particularly so since the 2000s. This study aimed at summarizing and analysing the information gathered from RUMs used during the last three decades around the globe. A methodology has been developed to standardize information across different studies and compare RUM results. The studies selected focused on fishing effort allocation. Six types of fisher behaviour drivers were considered: the presence of other vessels in the same fishing area, tradition, expected revenue, species... |
| Tipo: Text |
Palavras-chave: Fisher behaviour; Meta-analysis; Random utility model. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00357/46834/47127.pdf |
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| Calderwood, Julia; Robert, Marianne; Pawlowski, Lionel; Vermard, Youen; Radford, Zachary; Catchpole, Thomas L.; Reid, David G.. |
| As a result of the introduction of the Landing Obligation in European fisheries there is a need to equip industry with the tools and knowledge to avoid unwanted catches. Optimising fishing practices in terms of time and location fished have been acknowledged as being important in modulating catch composition. Mapping techniques used to identify and manage the spatio-temporal nature of bycatch, however, remain underutilized. Data collected on board commercial fishing vessels by observers provides an important source of information on the component of catches discarded. Using a unique dataset, combining observer data for Irish, French and British vessels operating in the Celtic Sea between 2010 and 2015, maps were developed to identify where catches of quota... |
| Tipo: Text |
Palavras-chave: Landing obligation; Discards; Consistent maps; Fishing tactics; Shiny app; Celtic sea. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00590/70162/68235.pdf |
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| Vermard, Youen; Lehuta, Sigrid; Mahevas, Stephanie; Thebaud, Olivier; Marchal, Paul; Gascuel, Didier. |
| It is increasingly recognized that fisher‟s behavior should be taken into account to understand and predict fishery dynamics, in particular in response to management. ISIS-Fish is a spatially and seasonally explicit modeling framework especially designed to couple populations and fleets dynamics and explore the impact of various management measures on mixed fisheries. It has already been set up using a static fishing effort allocation (corresponding to an average historical pattern) between the various métiers to simulate the pelagic fishery in the Bay of Biscay. We present here the integration of a fleet dynamics model. This model is derived from a Random Utility Model simulating métiers choice using as explanatory variables the past value per unit... |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00107/21858/19449.pdf |
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| Registros recuperados: 51 | |
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