Sylvie Guenette

EcOceans, St. Andrews, NB, Canada

Trophic models are key tools to go beyond the single-species approaches used in stock assessments to adopt a more holistic view and implement the Ecosystem Approach to Fisheries Management (EAFM). This study aims to: (i) analyse the trophic functioning of the Celtic Sea and the Bay of Biscay, (ii) investigate ecosystem changes over the 1980–2013 pe...

Trophic models are key tools to go beyond the single-species approaches used in stock assessments to adopt a more holistic view and implement the Ecosystem Approach to Fisheries Management (EAFM). This study aims to: (i) analyse the trophic functioning of the Celtic Sea and the Bay of Biscay, (ii) investigate ecosystem changes over the 1980–2013 pe...

Using the Bay of Biscay and Celtic Sea area as a case study, we showed how stock-assessments and trophic models can be useful and complementary tools to quantify the fishing impacts on the whole food web and to draw related diagnoses at the scale of marine ecosystems. First, an integrated synthesis of the status and trends in fish stocks, derived f...

Stock-based and ecosystem-based indicators are used to provide a new diagnosis of the fishing impact and environmental status of European seas. In the seven European marine ecosystems covering the Baltic and the North-eastern Atlantic: i) trends in landings since 1950 were examined; ii) syntheses of the status and trends in fish stocks were consoli...

Based on the Mauritanian case study, this presentation shows how the EcoTroph model (Gascuel et al., 2011) can be used to build global diagnosis of the ecosystem impact of fishing, and to analyze interactions between fleets targeting various compartments of the ecosystem. We used a preexisting EwE model, which includes 51 trophic groups and covers...

Current trajectories of global change may lead to regime shifts at regional scales, driving coupled human–environment systems to highly degraded states in terms of biodiversity, ecosystem services, and human well-being. For business-as-usual socioeconomic development pathways, regime shifts are projected to occur within the next several decades, to...

Climate change is expected to cause profound changes in marine ecosystems that will vary in magnitude and effect among regions. We explore the potential effects of climate change on the western Scotian Shelf ecosystem in eastern Canada using an ecosystem model and two scenarios of climatic changes. The model includes the effects of temperature, pH,...

Most modelling studies addressed the effectiveness of marine protected areas (MPA) for fisheries sustainability through single species approach. Only a few models analysed the potential benefits of MPAs at the ecosystem level, estimating the potential export of fish biomass from the reserve or analysing the trophic relationships between organisms i...

The report reviews the ecological role of forage fish globally and in Canada, and the policy directed at their management, with a focus on the consumption requirements of predators. The report is intended for policy makers, managers and biologists who are engaged in providing advice or making decisions concerning the management of forage species.

The report reviews the ecological role of forage fish globally and in Canada, and the policy directed at their management, with a focus on the consumption requirements of predators. The report is intended for policy makers, managers and biologists who are engaged in providing advice or making decisions concerning the management of forage species.

The report reviews the ecological role of forage fish globally and in Canada, and the policy directed at their management, with a focus on the consumption requirements of predators. The report is intended for policy makers, managers and biologists who are engaged in providing advice or making decisions concerning the management of forage species.

The present study describes the food web and evaluates the effects of a marine protected area (MPA), the Port-Cros National Park (NW Mediterranean Sea), on the marine ecosystem inside the reserve and its potential to sustain resources outside the reserve. We built an Ecopath model of the Port-Cros MPA which comprised 41 functional groups and repres...

The present study describes the food web and evaluates the effects of a marine protected area (MPA), the Port-Cros National Park (NW Mediterranean Sea), on the marine eco - system inside the reserve and its potential to sustain resources outside the reserve. We built an Ecopath model of the Port-Cros MPA which comprised 41 functional groups and rep...

Des modèles écosystémiques pour évaluer les effets des AMPs : démarches et enseignements du projet Amphore

Measurements of annual increments on cross-sections of the first ray of the pectoral fin of 125 St. Lawrence River female lake sturgeon (Acipenser fulvescens) aged 24 yr and older were used to test the correspondance between growth patterns at the margin of the sections and the state of maturity of the fish. For each of the 21 females aged 34 yr an...

Restriction fragment length pattern analysis of mitochondrial DNA (mtDNA) was used to assess genetic differentiation in sympatric lake sturgeon (Acipenser fulvescens) from the St. Lawrence River drainage basin (St. Lawrence and Ottawa rivers and Lac des Deux Montagnes) and in sturgeon from the Waswanipi River (James Bay drainage basin). Using 14 re...

We investigated the degree of morphological differentiation of lake sturgeon (Acipenser fulvescens) from the St. Lawrence River (Lacs Saint-Pierre and Saint-Louis and the river itself downstream from Lac Saint-Pierre) and from Lac des Deux Montagnes. Forty-one morphometric characters (traditional and truss network) and two meristic traits were used...

Determinants of variations in growth in length and body condition of take sturgeon (Acipenser fulvescens) were studied on 32 lake and river systems covering most of the distribution of the species. The average of mean total lengths at ages 23-27 years and the weight of a 1000-mm specimen were chosen as growth and condition indicators. A latitudinal...

Adult and juvenile mobility has a considerable influence on the functioning of marine protected areas. It is recognized that adult and juvenile movement reduces the core benefits of protected areas, namely protecting the full age-structure of marine populations, while at the same time perhaps improving fisheries yield over the no-reserve situation...

Catches per unit of effort (CPUE) with experimental gill nets, recruitment, growth, and condition were monitored between 1977 and 1992 to evaluate the impact of impoundment on the main fish species of La Grande 2, Opinaca, and Caniapiscau reservoirs and the Boyd–Sakami diversion. CPUE and recruitment of northern pike (Esox lucius) and lake whitefis...

Gascuel, D., Guénette, S., and Pauly, D. 2011. The trophic-level-based ecosystem modelling approach: theoretical overview and practical uses. – ICES Journal of Marine Science, 68: 1403–1416. A trophic-level (TL)-based ecosystem modelling approach is presented, where ecosystem functioning is modelled as a flow of biomass up the foodweb through preda...

Quantitative scenarios are coming of age as a tool for evaluating the impact of future socioeconomic development pathways on biodiversity and ecosystem services. We analyze global terrestrial, freshwater, and marine biodiversity scenarios using a range of measures including extinctions, changes in species abundance, habitat loss, and distribution s...

Quantitative scenarios are coming of age as a tool for evaluating the impact of future socioeconomic development pathways on biodiversity and ecosystem services. We analyze global terrestrial, freshwater, and marine biodiversity scenarios using a range of measures including extinctions, changes in species abundance, habitat loss, and distribution s...

La Parguera, Puerto Rico, a well-studied Caribbean reef system, is showing signs of overfishing and thus, is a good candidate to evaluate fishery policy scenarios using ecosystem modeling. The first steps taken to build a plausible ecosystem model of the La Parguera reef system using Ecopath with Ecosim software included synthesizing fisheries and...

In the 1980s, personnel from the Instituto del Mar del Peru collaborated with foreign experts to reconstruct time series of (1) catch and biomass of the Peruvian anchovy Engraulis ringens back to 1953, along with parallel time series of (2) abundance of anchovy predators and competitors, and (3) abiotic parameters indicative of the dynamics of the...

Mauritania is characterised by fast-growing fisheries that have developed over the past decades. Since 1982, scientific trawl surveys have been conducted regularly, allowing assessment of the impact of this increasing fishing pressure on exploited species as well as on demersal communities. Based on 55 bottom trawl surveys and using linear model te...

This is the first study on the emergent properties for empirical ecosystem models that have been validated by time series information. Ecosystem models of the western and central Aleutian Islands and Southeast Alaska were used to examine indices of ecosystem status generated from network analysis and incorporated into Ecopath with Ecosim. Dynamic s...

There is a wave of interest in Marine Protected Areas (MPA) and Integrated Management (IM) as tools for addressing declines in marine environments through ecosystem-based management. Lessons learned from seven MPA and two IM initiatives in Canada show how engaging stakeholders results in: building and maintaining momentum through social capital; us...

Steller sea lions (Eumetopias jubatus) increased in the eastern portion of their range while declining in the Gulf of Alaska and Aleutian Islands from the late 1970s to late 1990s. We constructed ecosystem models of the central and western Aleutians and of southeast Alaska to simultaneously evaluate four hypotheses explaining sea lion dynamics: kil...

Steller sea lions (Eumetopias jubatus) increased in the eastern portion of their range while declining in the Gulf of Alaska and Aleutian Islands from the late 1970s to late 1990s. We constructed ecosystem models of the central and western Aleutians and of southeast Alaska to simultaneously evaluate four hypotheses explaining sea lion dynam-ics: ki...

We compiled the abundance information for whales of the North Pacific for the 20th century, and compared it with their catch history and distributions. This information was necessary to complete the Gulf of Alaska models (this volume). We concentrated on the commercially important whales: fin, sei, gray, sperm and humpback. Examination of the catch...

We estimate the biomass of high-trophic level fishes in the North Atlantic at a spatial scale of 0.5° latitude by 0.5° longitude based on 23 spatialized ecosystem models, each constructed to represent a given year or short period from 1880 to 1998. We extract over 7800 data points that describe the abundance of high-trophic level fishes as a functi...

Fisheries have rarely been 'sustainable'. Rather, fishing has induced serial depletions, long masked by improved technology, geographic expansion and exploitation of previously spurned species lower in the food web. With global catches declining since the late 1980s, continuation of present trends will lead to supply shortfall, for which aquacultur...

Abstract To evaluate the impacts of ¢shing on marine ecosystems, the total extraction of ¢sh must be known. Putting a ¢gure on total extraction entails the di⁄cult task of estimat- ing, in addition to reported landings, discards, illegal and unmandated catches. Unre- ported catches cast various types of shadow, which may be tracked and estimated qu...

We present a summary of the historical French cod fishery off the coast of Newfoundland, based mainly on landings and vessel data from a study by Hersart de la Villemarqué published by IFREMER in 1995. Cod landings and the number of boats increased periodically from 1550-1914. The onset of the First World War resulted in a dramatic reduction in the...

Catch statistics are presented for the Azores Islands (Portugal) by type of fishery. These data were compared with the official ICES statistics (STATLANT) for the years 1982-1999. This represents the time period for which detailed catch statistics have been collected in the Azores. For each fishery, the proportion of under-reported catch is estimat...

Estimation of total harvests of marine organisms is es- sential if true impacts of fisheries are to be evaluated. Such estimates are difficult to obtain because, for many of the world's fisheries, an unknown proportion of the catch is not reported. Components of the unreported catch may include discards, deliberately misreported catch and unmandate...

ABSTRACT The Azores Archipelago ,consists of a small shelf surrounded,by a large component,of deep oceanic waters dotted with seamounts.,The present model is structured,by depth,and constitutes a first step inapplying,the Ecopath ,modeling ,approach ,to Atlantic,seamounts. ,It is the ,result ,of a collaborative effort with several researchers,of th...

This paper documents the construction of the model of the Atlantic coast of Morocco including the coast of Western Sahara (Tangier to Cape Blanc). The model includes 37 functional groups of which 23 are fishes, grouped by size and commercial importance. The balancing process is described and highlights knowledge gaps. Recommendations for improvemen...

This article is a synthesis of the current literature on the potential of marine protected areas (MPAs) a useful management tool for limiting the ecosystem effects of fishing, including biological and socio-economic aspects. There is sufficient evidence that fishing may negatively affect ecosystems. Modelling and case studies show that the establis...

Marine reserves (areas closed to exploitation of marine life) should allow better resilience to management errors such as overestimation of stocks, inadequate control of fishing effort, and inaccurate catch statistics. We employed a detailed population model to explore the use of marine reserves to protect cod populations from overexploitation. The...

The South China Sea has been devastated by human fishing. This paper reports an initiative to restore Hong Kong's marine ecosystems and fisheries through the deployment of artificial reefs (ARs) within marine protected areas (MPAs). Current catch and biomass data by species and fishery sector were available. Quasi-spatial ecosystem simulations, usi...

Marine reserves (areas closed to exploitation of marine life) should allow better resilience to management errors such as overestimation of stocks, inadequate control of fishing effort, and inaccurate catch statistics. We employed a detailed population model to explore the use of marine reserves to protect cod populations from overexploitation. The...

Interpretation of the behavioural dynamics and distribution of herring requires explicit consideration of spatial and temporal scales since no single mechanism can explain the pattern on all scales. High resolution sonar and echosounders were used as our observation tools. The cluster ratio, mean Nearest Neighbour Distance (mean ISD): mean of the a...

Previous modelling of areas closed to fishing (marine reserves) has generally employed non-dynamic models and has not included biological factors such as stock–recruitment and weight–fecundity relations. These models predicted that a marine reserve would result in a decrease in fishery yield, an increase in spawning biomass and that movements of fi...

This paper provides a synthesis of the current literature on the potential of marine protected areas (MPAs) as a management tool to limit the ecosystem effects of fishing, including biological and socio-economic perspectives. There is sufficient evidence to show that fishing can indeed negatively impact ecosystems. Modelling and case studies show t...

The idea of using marine reserves, where all fishing is banned is not new to fisheries management. It was first formally considered by Beverton and Holt but rejected in favour of approaches such as fleet and gear control. Since that analysis, many fisheries have collapsed worldwide, illustrating the vulnerability of fishery resources and the ineffe...

Catches per unit of effort (CPUE) with experimental gill nets, recruitment. growth. and condition were monitored between 1977 and 1992 to evaluate the impact of impoundment on the main fish species of La Grande 2, Opinaca, and Caniapiscau reservoirs and the Boyd-Sakami diversion. CPUE and recruitment of northern pike (Esox lucius) and lake whitefis...

Sainte Anne River tomcod spawn in a rapids sector, located approximately 7 km upstream from the confluence with the Saint Lawrence River, and probably also in a sector of accumulation of frasil ice generated in the rapids. The interannual variations in the drift of tomcod eggs and larvae, at different stations in the Sainte Anne River, were related...

Because of the geographical proximity between Spain and Africa, and the poor resources around the Canary Islands, the fishers from the southern region of the Spanish mainland (Andalusia) and from the Canary Islands have been fishing along the African coast very early in history. Boats operating from the Canaries exploited resources on the Saharan c...

We constructed ecosystem models using the Ecopath with Ecosim software to evaluate whether predation by killer whales might explain the decline of Steller sea lions since the late 1970s in the central and western Aleutian Islands. We also sought to understand why sea lions increased in the presence of killer whales in Southeast Alaska. Modelling re...

Coral reef ecosystems, such as the well-studied La Parguera reef system (SW Puerto Rico), exhibit complex interactions with consequences difficult to predict with conventional fisheries management models. A newly-developed trophic model, based on Ecopath with Ecosim, offers an alternative means to evaluate fishing policies that might achieve desira...