Effects of fishing and predation in a heavily exploited ecosystem: Comparing periods before and after the collapse of groundfish in the southern Gulf of St. Lawrence (Canada)

Savenkoff, Claude; Swain, Douglas P.; Hanson, John Mark; Castonguay, Martin; Hammill, Mike O.; Bourdages, Hugo; Morissette, Lyne; Chabot, Denis

doi:10.1016/j.ecolmodel.2006.12.029

Cited by 70 publications

(60 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This phenomenon has been observed in a large number of studies that use mass balance trophic models as analytical tools (e.g. Albouy et al, 2010;Barausse et al, 2009;Coll et al, 2008aColl et al, , 2008bColl et al, , 2009aColl et al, , 2009bHinke et al, 2004;Jones et al, 2009;Savenkoff et al, 2007aSavenkoff et al, , 2007b.…”

Section: Structural Simplificationmentioning

confidence: 99%

“…However, these are not the only possible or documented changes in alternate stable states or phase shifts in an ecosystem (Scheffer, 2010). For example, Savenkoff et al (2007aSavenkoff et al ( , 2007b identified, in addition to a change in network dominance, a change in predator structure because the reduction in large pelagic fish abundance allowed for marine mammals to be the only top predators in the system. Along the same lines, a decrease in mean size of the catch has been found in different ecosystems as well as a reduction in mean weight of species and www.intechopen.com specimens caught (Zwanenburg, 2000).…”

Section: Structural Changes and Phase Shiftsmentioning

confidence: 99%

“…More specifically, generalized effects are reductions in biomass of top predators and an increase in the proportion of species at intermediate trophic levels and basal species, suggesting that fishing is shifting ecosystem structure from large species with low abundance and slow developmental cycles to small species with high abundance and faster developmental cycles (Albouy et al, 2010;AriasGonzález et al, 2004;Barausse et al, 2009;Chen et al, 2008;Coll et al, 2007Coll et al, , 2008aColl et al, , 2009aColl et al, , 2009bColl et al, , 2010Duan et al, 2009;Lotze et al, 2011;Savenkoff et al, 2007aSavenkoff et al, , 2007b. This generalized effect is reducing the naturally occurring competition among the original species in the network and facilitating the onset of indirect effects that generate competition among species that did not strongly interact before.…”

Section: Ecopath With Ecosim As a Tool To Detect The Effect Of Fishinmentioning

confidence: 99%

See 2 more Smart Citations

Changes to Marine Trophic Networks Caused by Fishing

Navia¹,

Cortés²,

Jordán³

et al. 2012

Diversity of Ecosystems

View full text Add to dashboard Cite

Section: Structural Simplificationmentioning

confidence: 99%

Section: Structural Changes and Phase Shiftsmentioning

confidence: 99%

Section: Ecopath With Ecosim As a Tool To Detect The Effect Of Fishinmentioning

confidence: 99%

See 1 more Smart Citation

Changes to Marine Trophic Networks Caused by Fishing

Navia¹,

Cortés²,

Jordán³

et al. 2012

Diversity of Ecosystems

View full text Add to dashboard Cite

“…This boreal subarctic region experiences both 'top-down' structuring of community dynamics (e.g. Savenkoff et al 2007b), where a predominant predator is Atlantic cod Gadus morhua, and 'bottomup' forcing, which is more tightly linked to environmental change (e.g. Greene et al 2008).…”

Section: Introductionmentioning

confidence: 99%

Environmental mediation of Atlantic cod on fish community composition: an application of multivariate regression tree analysis to exploited marine ecosystems

Ruppert¹,

Fortin²,

Rose³

et al. 2010

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Changes in species abundances caused by climatic variability have long been linked to alterations in community composition, species interactions and maintenance of biodiversity in marine ecosystems. Here we use multivariate regression tree (MRT) analyses to quantify how changes in species abundances and environmental variability contributed to observed patterns of community composition in the Gulf of St. Lawrence during 2 contrasting periods (the cooler and less saline period 1991 to 1995 and the warmer and more saline period 1997 to 2003). Broad-scale patterns of community composition in both periods were consistently explained by the depth and salinity of the benthic environment, but biological factors differed. In the cold period, the previous year's catches of snow crab Chionoecetes opilio and northern shrimp (mainly Pandalus borealis) were most important, while in the warm period the previous year's catch of Atlantic cod Gadus morhua dominated. MRT models further identified spatially discrete areas where communities are characterized by relatively high abundances of these species. These results indicate that environmental variability leads to dynamic and spatially explicit responses not only of single species, but of marine communities. Applications of ecosystem management in the face of climate change must take this into account.

show abstract

“…These studies have demonstrated the importance of northern shrimp in the diet of cod, but have also noted that the contribution by northern shrimp to the cod diet can vary greatly with area (Rose & O'Driscoll 2002), time of year (Pálsson & Björnsson 2011) and size of cod (Albers & Anderson 1985, Berenboim et al 2000. The consumption of northern shrimp by cod can also be quite variable over years (Mehl 1989, Pálsson & Björnsson 2011, and sometimes it may represent a greater source of mortality than commercial fishing pressure (Savenkoff et al 2007).…”

Section: Introductionmentioning

confidence: 99%

Predation by Atlantic cod Gadus morhua on northern shrimp Pandalus borealis in inshore and offshore areas of Iceland

Jónsdóttir¹,

Björnsson²,

Skúladóttir³

2012

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Northern shrimp Pandalus borealis is found in both inshore and offshore areas around Iceland, where it has supported an important commercial fishery. However, in the past 15 yr the northern shrimp population has decreased in size and collapsed in most of the inshore areas. In this study, the importance of Atlantic cod Gadus morhua on northern shrimp stock dynamics was studied by comparing stomach contents of cod between 2 different habitats, inshore and offshore northern shrimp fishery areas. Many prey items were observed in cod stomachs, but only a few dominated. The most important prey types, in decreasing order of importance, included northern shrimp, fish and euphausiids in the inshore area, as opposed to capelin Mallotus villosus, other fish species, northern ambereye Hymenodora glacialis and northern shrimp in the offshore area. Low northern shrimp biomass was observed during periods of high cod density, suggesting that predation by cod affected northern shrimp biomass in both areas. KEY WORDS: Northern shrimp · Cod · Predation · Species interaction · Temperature Resale or republication not permitted without written consent of the publisher Contribution to the Theme Section 'Effects of climate and predation on subarctic crustacean populations'OPEN PEN

show abstract

Effects of fishing and predation in a heavily exploited ecosystem: Comparing periods before and after the collapse of groundfish in the southern Gulf of St. Lawrence (Canada)

Cited by 70 publications

References 32 publications

Changes to Marine Trophic Networks Caused by Fishing

Changes to Marine Trophic Networks Caused by Fishing

Environmental mediation of Atlantic cod on fish community composition: an application of multivariate regression tree analysis to exploited marine ecosystems

Predation by Atlantic cod Gadus morhua on northern shrimp Pandalus borealis in inshore and offshore areas of Iceland

Contact Info

Product

Resources

About