Results
author = "Bertignac, Michel"
Consequences of bias in age estimation on assessment of the northern stock of European hake (Merluccius merluccius) and on management advice
Description :
The results of a pilot tagging study on hake (Merluccius merluccius), conducted in the northern part of the Bay of Biscay in 2002, indicate that growth rates for this stock may be currently underestimated because of biased estimates of age. The impact that such a bias may have on the stock dynamics ...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Assessing the impact of discretisation assumptions in a length-structured population growth model
Description :
Most of the traditional assessment models are age-structured. However, many biological and exploitation processes are more length-dependent than age-dependent, and the required length-age conversion of available data is often not reliable. Consequently, length-structured or age-length structured mod...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Analysis of tagging data from North Atlantic Albacore (Thunnus Alalunga): Attrition Rate Estimates
Description :
In this study, an attempt is made to estimate natural mortality rate for North Atlantic albacore. We implement a spatially aggregated tag-attrition model to analyse the results of an albacore tagging experiment conducted in the Bay of Biscay from 1988 to 1991. The model predicts probabilities of th...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
A cost-benefit analysis of improving trawl selectivity in the case of discards: The Nephrops norvegicus fishery in the Bay of Biscay
Description :
The Nephrops trawl fishery is one of the most important fisheries in the Bay of Biscay. The fishery management essentially relies on conservation measures, a total at I owed catch (TAC) for Nephrops together with a mini mum landing size (MLS) and minimum trawl mesh size (70 mm stretched mesh). These...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
A length-structured spatially explicit model for estimating hake growth and migration rates
Description :
Drouineau, H., Mahevas, S., Bertignac, M., and Duplisea, D. 2010. A length-structured spatially explicit model for estimating hake growth and migration rates. - ICES Journal of Marine Science, 67: 1697-1709.
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Evidence of underestimation of European hake growth in the Bay of Biscay, and its relationship with bias in the agreed method of age estimation
Description :
In 2002, a pilot experiment on hake tagging was carried out using methodology specifically developed to catch and handle fish in,good condition. By the end of 2005, 36 hake and five tags had been returned to the laboratory (a 3.1% return rate) with a maximum time at liberty of 1066 days. The somatic...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
A stochastic viability approach to ecosystem-based fisheries management
Author(s) :
Doyen, Luc
,
Thebaud, Olivier
,
Bene, Christopher
,
Martinet, V.
,
Gourguet, S.
,
Bertignac, Michel
,
Fifas, Spyros
,
Blanchard, Fabian
Description :
Academia and management agencies show a growing interest for ecosystem-based fishery management (EBFM). However, the way to operationalize this approach remains challenging. The present paper illustrates how the concepts of stochastic co-viability, which accounts for dynamic complexities, uncertaint...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Evaluation du stock de palourdes du bassin d'Arcachon
Author(s) :
Bertignac, Michel
,
Auby, Isabelle
,
Sauriau, Pierre-guy
,
De Montaudouin, Xavier
,
Foucard, Julie
,
Martin, Sophie
Description :
As part of a larger project financed by the European Union programme "Community initiative PESCA" on the study of "small scale fisheries" in Aquitaine (France), an estimation of the stock of clams in the Bassin d'Arcachon has been conducted. A two-stage stratified random sampling survey has been des...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
French
A bio-economic analysis of experimental selective devices in the Norway lobster (Nephrops norvegicus) fishery in the Bay of Biscay
Author(s) :
Raveau, Adriana
,
Macher, Claire
,
Mehault, Sonia
,
Merzereaud, Mathieu
,
Le Grand, Christelle
,
Guyader, Olivier
,
Bertignac, Michel
Description :
Several fleets with various fishing strategies operate as a mixed fishery in the Bay of Biscay. Among the main fleets, bottom trawlers target Norway lobster (Nephrops norvegicus) and, together with gillnetters, they also catch hake (Merluccius merluccius). Trawling leads to average-size catches that...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Situation en 2011 des ressources exploitées par les flottilles françaises
Author(s) :
Biseau, Alain
,
Bellail, Robert
,
Bertignac, Michel
,
Biais, Gerard
,
Bigot, Jean-louis
,
Bouche, Ludovic
,
Bourjea, Jerome
Description :
Ce document présente l'état des principaux stocks exploités par les flottes françaises en termes de mortalité par pêche et de biomasse de reproducteurs. La situation fin 2010 (début 2011) par rapport aux points de référence (de précaution et Fmsy) est indiqué lorsque les indicateurs sont estimés et ...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
French