|
|
|
|
| |
|
|
Fu, Caihong; Xu, Yi; Grüss, Arnaud; Bundy, Alida; Shannon, Lynne; Heymans, Johanna J; Halouani, Ghassen; Akoglu, Ekin; Lynam, Christopher P; Coll, Marta; Fulton, Elizabeth A; Velez, Laure; Shin, Yunne-jai. |
Marine ecosystems are influenced by multiple stressors in both linear and non-linear ways. Using generalized additive models (GAMs) fitted to outputs from a multi-ecosystem, multi-model simulation experiment, we investigated 14 major ecological indicators across ten marine ecosystems about their responses to fishing pressure under: (i) three different fishing strategies (focusing on low-, high-, or all-trophic-level taxa); and (ii) four different scenarios of directional or random primary productivity change, a proxy for environmental change. From this work, we draw four major conclusions: (i) responses of indicators to fishing mortality in shapes, directions, and thresholds depend on the fishing strategies considered; (ii) most of the indicators... |
Tipo: Text |
|
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00516/62749/67138.pdf |
| |
|
|
Kleisner, Kristin M.; Coll, Marta; Lynam, Christopher P.; Bundy, Alida; Shannon, Lynne; Shin, Yunne-jai; Boldt, Jennifer L.; Borges, Maria F.; Diallo, Ibrahima; Fox, Clive; Gascuel, Didier; Heymans, Johanna J.; Juan Jorda, Maria J.; Jouffre, Didier; Large, Scott I.; Marshall, Kristin N.; Ojaveer, Henn; Piroddi, Chiara; Tam, Jorge; Torres, Maria A.; Travers-trolet, Morgane; Tsagarakis, Konstantinos; Van Der Meeren, Gro I.; Zador, Stephani. |
Fisheries provide critical provisioning services, especially given increasing human population. Understanding where marine communities are declining provides an indication of ecosystems of concern and highlights potential conflicts between seafood provisioning from wild fisheries and other ecosystem services. Here we use the nonparametric statistic, Kendall׳s tau, to assess trends in biomass of exploited marine species across a range of ecosystems. The proportion of ‘Non-Declining Exploited Species’ (NDES) is compared among ecosystems and to three community-level indicators that provide a gauge of the ability of a marine ecosystem to function both in provisioning and as a regulating service: survey-based mean trophic level, proportion of predatory fish,... |
Tipo: Text |
Palavras-chave: Ecological indicator; Comparative approach; Community metric; IndiSeas; Fishing impacts. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00254/36555/35186.pdf |
| |
|
|
Cury, Philippe; Boyd, Ian L.; Bonhommeau, Sylvain; Anker-nilssen, Tycho; Crawford, Robert J. M.; Furness, Robert W.; Mills, James A.; Murphy, Eugene J.; Oesterblom, Henrik; Paleczny, Michelle; Piatt, John F.; Roux, Jean-paul; Shannon, Lynne; Sydeman, William J.. |
Determining the form of key predator-prey relationships is critical for understanding marine ecosystem dynamics. Using a comprehensive global database, we quantified the effect of fluctuations in food abundance on seabird breeding success. We identified a threshold in prey (fish and krill, termed "forage fish") abundance below which seabirds experience consistently reduced and more variable productivity. This response was common to all seven ecosystems and 14 bird species examined within the Atlantic, Pacific, and Southern Oceans. The threshold approximated one-third of the maximum prey biomass observed in long-term studies. This provides an indicator of the minimal forage fish biomass needed to sustain seabird productivity over the long term. |
Tipo: Text |
|
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00056/16770/14307.pdf |
| |
|
|
Fu, Caihong; Xu, Yi; Bundy, Alida; Grüss, Arnaud; Coll, Marta; Heymans, Johanna J.; Fulton, Elizabeth A.; Shannon, Lynne; Halouani, Ghassen; Velez, Laure; Akoğlu, Ekin; Lynam, Christopher P.; Shin, Yunne-jai. |
Moving toward ecosystem-based fisheries management (EBFM) necessitates a suite of ecological indicators that are responsive to fishing pressure, capable of tracking changes in the state of marine ecosystems, and related to management objectives. In this study, we employed the gradient forest method to assess the performance of 14 key ecological indicators in terms of specificity, sensitivity and the detection of thresholds for EBFM across ten marine ecosystems using four modelling frameworks (Ecopath with Ecosim, OSMOSE, Atlantis, and a multi-species size-spectrum model). Across seven of the ten ecosystems, high specificity to fishing pressure was found for most of the 14 indicators. The indicators biomass to fisheries catch ratio (B/C), mean lifespan and... |
Tipo: Text |
Palavras-chave: Ecological modelling; Fishing pressure; Gradient forest method; Indictor performance; Marine ecosystem; Primary productivity. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00500/61148/64576.pdf |
| |
|
|
Shannon, Lynne; Coll, Marta; Bundy, Alida; Gascuel, Didier; Heymans, Johanna J;; Kleisner, Kristin; Lynam, Christopher; Piroddi, Chiara; Tam, Jorge; Travers-trolet, Morgane; Shin, Yunne. |
Trophic level (TL)-based indicators have been widely used to examine fishing impacts in aquatic ecosystems and the induced biodiversity changes. However, much debate has ensued regarding discrepancies and challenges arising from the use of landings data from commercial fisheries to calculate TL indicators. Subsequent studies have started to examine survey-based and model-based indicators. In this paper, we undertake an extensive evaluation of a variety of TL indicators across 9 well-studied marine ecosystems by making use of model- as well as surveyand catch-based TL indicators. Using detailed regional information and data on fishing history, fishing intensity, and environmental conditions, we evaluate how well TL indicators are capturing fishing effects... |
Tipo: Text |
Palavras-chave: Trophic level; Global comparison; Indicator; Survey; Catch; Ecosystem model; Trophic spectra; Convention on Biological Diversity; Food webs; Ecosystem approach to fisheries. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00222/33361/31768.pdf |
| |
|
|
Rose, Kenneth A.; Allen, J. Icarus; Artioli, Yuri; Barange, Manuel; Blackford, Jerry; Carlotti, Francois; Cropp, Roger; Daewel, Ute; Edwards, Karen; Flynn, Kevin; Hill, Simeon L.; Hillerislambers, Reinier; Huse, Geir; Mackinson, Steven; Megrey, Bernard; Moll, Andreas; Rivkin, Richard; Salihoglu, Baris; Schrum, Corinna; Shannon, Lynne; Shin, Yunne-jai; Smith, S. Lan; Smith, Chris; Solidoro, Cosimo; St John, Michael; Zhou, Meng. |
There is growing interest in models of marine ecosystems that deal with the effects of climate change through the higher trophic levels. Such end-to-end models combine physicochemical oceanographic descriptors and organisms ranging from microbes to higher-trophic-level (HTL) organisms, including humans, in a single modeling framework. The demand for such approaches arises from the need for quantitative tools for ecosystem-based management, particularly models that can deal with bottom-up and top-down controls that operate simultaneously and vary in time and space and that are capable of handling the multiple impacts expected under climate change. End-to-end models are now feasible because of improvements in the component submodels and the availability of... |
Tipo: Text |
|
Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00483/59488/62350.pdf |
| |
|
|
|