Le concept d’approche écosystémique appliqué à l’estuaire maritime du Saint-Laurent (Canada)

Savenkoff, Claude; Gagné, Jacques; Gilbert, Michel; Castonguay, Martin; Chabot, Denis; Chassé, Joël; Comtois, Sophie; Dutil, Jean‐Denis; Galbraith, Peter S.; Gosselin, Jean‐François; Grégoire, François; Larocque, Richard; Larouche, Pierre; Lavoie, Diane; Lebeuf, Michel; Lesage, Véronique; Maps, Frédéric; McQuinn, Ian H.; Mosnier, Arnaud; Nozères, Claude; Ouellet, Patrick; Plourde, Stéphane; Sainte‐Marie, Bernard; Savard, Louise; Scarratt, Michael; Starr, Michel

doi:10.1139/er-2015-0083

Cited by 5 publications

(4 citation statements)

References 220 publications

(244 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Data on shrimp biomass were not included in the analyses. Although shrimps are considered as "benthic" organisms, they are not permanently located on the seabed, undertaking vertical migrations, and thus limiting their link to the benthic habitat (DFO, 2002;Savenkoff et al, 2017). Indeed, only 30% of shrimp diets come from the benthos with the remaining 70% originating from pelagic food webs (Bundy et al, 2000).…”

Section: Epibenthic Community Structurementioning

confidence: 99%

“…Indeed, only 30% of shrimp diets come from the benthos with the remaining 70% originating from pelagic food webs (Bundy et al, 2000). Moreover, northern shrimp Pandalus borealis represents 75% of the invertebrate catch of all EGSL surveys and its inclusion in the analyses could mask trends for other epibenthic taxa (Savenkoff et al, 2017). All data analyses were done using R version 3.5.1.…”

Section: Epibenthic Community Structurementioning

confidence: 99%

See 1 more Smart Citation

Detection of Ecological Thresholds and Selection of Indicator Taxa for Epibenthic Communities Exposed to Multiple Pressures

et al. 2021

View full text Add to dashboard Cite

The estuary and the Gulf of St. Lawrence (EGSL), eastern Canada form a vast inland sea that is subjected to numerous anthropogenic pressures. Management tools are needed to detect and quantify their effect on benthic communities. The aims of this study are to analyze the spatial distribution of epibenthic communities in the EGSL and quantify the impact of important pressures on them to identify indicator taxa. Epibenthic communities were sampled at 1314 EGSL sites between 2011 and 2018 by bottom trawling. Cluster analyses revealed the presence of six distinct epibenthic communities that seem to be strongly influenced by oxygen concentration. Threshold analyses confirm that oxygen is an important predictor of epibenthic community composition and distribution. A major oxygen threshold is observed around 50–100 μmol O2 L–1, resulting in a shift of community type. At these concentrations and below, opportunistic taxa dominate the community while sensitive taxa are absent or present at very low abundance. Biomass of the latter only starts to increase when oxygen concentrations reach 150 μmol O2 L–1. The species Actinostola callosa, Actinauge cristata, Ctenodiscus crispatus, and Brisaster fragilis were identified as good indicators for detecting this impact threshold forepibenthic communities. This study provides threshold-based indicator species that help to establish and monitor the ecological state of epibenthic communities in a marine ecosystem exposed to multiple pressures.

show abstract

Section: Epibenthic Community Structurementioning

confidence: 99%

Section: Epibenthic Community Structurementioning

confidence: 99%

Detection of Ecological Thresholds and Selection of Indicator Taxa for Epibenthic Communities Exposed to Multiple Pressures

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Moreover, the upstream transport within the Estuarine portion of the system undergoes a regime shift at the end of the summer (Lavoie et al ). This stratified temperature profile and circulation regime change has important consequences for the functioning of the EGSL planktonic ecosystem (Savenkoff et al ).…”

Section: Methodsmentioning

confidence: 99%

Individual‐based modeling explains the contrasted seasonality in size, growth, and reproduction of the sympatric Arctic (Thysanoessa raschii) and Nordic krill (Meganyctiphanes norvegica) in the St. Lawrence Estuary, eastern Canada

Benkort

Plourde

Winkler

et al. 2018

Limnology & Oceanography

View full text Add to dashboard Cite

The Nordic krill Meganyctiphanes norvegica and Arctic krill Thysanoessa raschii both dominate the krill community within the Estuary and Gulf of St. Lawrence system where they are central forage species for its pelagic ecosystem. We developed a species‐specific physiological individual based model that implements the critical physiological processes of growth, molting, and reproduction of female adults as responses to environmental forcing. Key innovations of our approach were the decoupling between the molting schedule and growth, as well as considering two distinct sources of prey (phytoplankton and mesozooplankton). Our simulation results revealed that the details of the feeding process were critical for an accurate representation of the production dynamics of adult individuals from both species. Their specific feeding preferences on phytoplankton and mesozooplankton resulted in distinct species‐specific phenological patterns that reproduced observations. The present study highlights the importance of detailed knowledge of diet and feeding behavior of krill species to improve our understanding of population responses in a rapidly changing environment.

show abstract

“…In the Northwestern Atlantic, fish populations of the Gulf of St Lawrence (hereafter GSL) are mostly threatened by overexploitation, climate change, and predation by expanding seal populations (Savenkoff et al 2017). Among the main fish species, mackerel (Scomber scombrus), herring (Clupea harengus) and cod (Gadus morhua) have a long history of fisheries , DFO 2016, 2017a.…”

Section: Introductionmentioning

confidence: 99%

Fish population growth in the Gulf of St Lawrence: effects of climate, fishing and predator abundance

Brosset¹,

Durant²,

Beveren³

et al. 2019

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Climate variability, fishing and predation are the main factors affecting fish population dynamics. In this study, the drivers of population growth variability were investigated for seven fish stocks (2 cod, 4 herring and 1 mackerel stock) in the Gulf of St. Lawrence (NW Atlantic). The annual population growth sensitivity to both recruitment and survival (how much population growth depends on recruitment and survival) was estimated through elasticity analyses before being linked to harvesting history as well as environmental conditions (climate and predation). Stock-specific generalized additive models showed that population growth was most sensitive to recruitment variability with decreasing fish generation time, increasing water temperature and, in some cases, with predation. The dependence of population growth on recruitment, however, was generally close to 0, albeit being higher for pelagic stocks than for demersal ones. This indicates that adult survival was more important than recruitment in shaping population growth and thus population size. As climate mainly acts on recruitment while fishing affects adult survival, management efforts seemed more important than climate variability in regulating population growth, especially for long-lived cod. Nevertheless, population growth may become increasingly dependent on recruitment variability with warming waters, hence, why more flexible management strategies should be developed to cope with these oscillations.

show abstract

Le concept d’approche écosystémique appliqué à l’estuaire maritime du Saint-Laurent (Canada)

Cited by 5 publications

References 220 publications

Detection of Ecological Thresholds and Selection of Indicator Taxa for Epibenthic Communities Exposed to Multiple Pressures

Detection of Ecological Thresholds and Selection of Indicator Taxa for Epibenthic Communities Exposed to Multiple Pressures

Individual‐based modeling explains the contrasted seasonality in size, growth, and reproduction of the sympatric Arctic (Thysanoessa raschii) and Nordic krill (Meganyctiphanes norvegica) in the St. Lawrence Estuary, eastern Canada

Fish population growth in the Gulf of St Lawrence: effects of climate, fishing and predator abundance

Contact Info

Product

Resources

About