Results
author = "Trenkel Verena"
A framework for qualitatively evaluating management plans in a results-based perspective
Description :
Currently many multi-year management plans are being developed either for rebuilding depleted stocks or for avoiding difficult negotiations when management decisions must be revisited on a regular basis. Management plans are commonly evaluated by intensive model simulations that describe the ecologi...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Exploring the abundance-occupancy relationships for the Georges Bank finfish and shellfish community from 1963 to 2006
Description :
Abundance-occupancy (A-O) patterns were explored temporally and spatially for the Georges Bank finfish and shellfish community to evaluate long-term trends in the assemblage structure and to identify anthropogenic and environmental drivers impacting the ecosystem. Analyses were conducted for 32 spec...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Capacity management, not stock status or economics, drives fleet dynamics in the Bay of Biscay ecosystem on a decadal time scale
Description :
This paper introduces a semiqualitative approach to analyse the joint dynamics of fleets and stocks in a multispecies, multifleet fishery. We ask whether changes in fleets affect resource dynamics and whether trends in resource influence fleet dynamics more than external drivers do. External drivers...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Space-time modelling of blue ling for fisheries stock management
Description :
Fishery catch data offer a rich potential source of information for management, if modelling can separate out the effects of fishing effort, species behaviour and population abundance. Here, we model catch data from the blue ling fishery off the northwest coast of Scotland, using generalised additiv...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Small-scale spatial and temporal interactions among benthic crustaceans and one fish species in the Bay of Biscay
Description :
In the summer of 2004, a video survey was carried out in the northern part of the central mud bank (Grande Vasiere) of the Bay of Biscay to study the small scale relationship between the dominant crustacean megafauna Nephrops norvegicus, Munida rugosa and Goneplax rhomboides and juvenile hake (Merlu...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Investigating trophic-level variability in Celtic Sea fish predators
Description :
The trophic level mean and variance, and the degree of omnivory for five Celtic Sea fish predators were estimated using a database of stomach content records characterized by a high level of taxonomic resolution. The predators occupied a high position in the food web, i.e. 4.75 for Atlantic cod Gadu...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Using cognitive maps to investigate fishers' ecosystem objectives and knowledge
Description :
This paper presents a survey of French Eastern English Channel fishers' observations of the past and current state of the marine ecosystem and their wishes for the future, as a first step towards formulating management objectives. Twenty-nine semi-directive interviews were carried out in June 2006 a...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
A review of fishery-independent assessment models, and initial evaluation based on simulated data
Description :
Large uncertainties in catch data (officially-reported landings and discards) are undermining the ability of scientific organisations to provide valid management advice based on the conventional approach of analytical stock assessments. There is thus an urgent need to consider alternative tools that...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Different surveys provide similar pictures of trends in a marine fish community but not of individual fish populations
Description :
Choice of sampling method and survey period can have an important impact on the perception of the structure and dynamics of an ecological community. For the Celtic Sea fish assemblage we compared data obtained by three different trawl surveys: an autumn groundfish survey with a GOV trawl, and a spri...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English
Precision and accuracy of fish length measurements obtained with two visual underwater methods
Description :
During the VIITAL cruise in the Bay of Biscay in summer 2002, two devices for measuring the length of swimming fish were tested: 1) a mechanical crown that emitted a pair of parallel laser beams and that was mounted on the main camera and 2) an underwater auto-focus video camera. The precision and a...
Repository :
Archimer, Archive Institutionnelle de l'Ifremer
Language(s) :
English