Article
Oceanography
Y. Li, H. Xie, M. G. Scarratt, E. Damm, P. S. Galbraith, N. Lambert, L. Geng, D. W. R. Wallace
Summary: This study presents the first data set of dissolved methane in the water column of the Estuary and Gulf of St. Lawrence. The Estuary and Gulf of St. Lawrence contribute a small proportion to global estuarine methane emissions, and complex physical-biogeochemical interactions control methane cycling and isotopic composition in this estuarine system.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Chemistry, Multidisciplinary
Duc Huy Dang, Dario Omanovic, Alfonso Mucci, Wei Wang, Allison Sikma, Anique Chatzis
Summary: This study reports the platinum concentrations in the Estuary and Gulf of St. Lawrence (EGSL) during winter, and compares its behavior with that of cadmium. The results show that the dissolved platinum concentrations in the EGSL during winter are higher than in most river systems and marine endmembers, likely due to the geology of the drainage basins and atmospheric deposition. In addition, the mixing behavior of platinum and cadmium in the surface waters of the EGSL during winter is near-conservative, while the concentrations increase in bottom waters, possibly due to various factors. This highlights the importance of considering winter and oxygen-depleted conditions in future platinum budget calculations.
Article
Multidisciplinary Sciences
Vang Y. Nguyen, Shannon M. Bayse, Paul D. Winger, Harold DeLouche, George Legge
Summary: This study developed a semi-pelagic trawl to target redfish in the Gulf of St. Lawrence and minimize bycatch and seabed impacts. The new trawl utilized an innovative technique to keep the trawl off the seabed and match the movement of redfish. The results suggest that redfish can be commercially targeted with this trawl, and the catch of bycatch species may be reduced.
Article
Environmental Sciences
Fella Moualek, Dominic Belanger, Mathieu Babin, Genevieve J. Parent, Dominic E. Ponton, Marc Amyot, Caroline Senay, Dominique Robert, Zhe Lu
Summary: Mercury pollution, particularly in the form of methylmercury, poses a significant threat to the environment. This study investigated the distribution of methylmercury and total mercury in the muscle of deep-sea redfish and assessed the associated health risks for humans consuming redfish. The study found that factors such as fish length, muscle moisture, and nitrogen levels influenced the concentrations of methylmercury in redfish muscle. However, the average fish consumption rate by the general population is not expected to have adverse effects.
ENVIRONMENTAL POLLUTION
(2023)
Article
Environmental Sciences
Anne Corminboeuf, Jean-Carlos Montero-Serrano, Richard St-Louis, Allyson Dalpe, Yves Gelinas
Summary: The study revealed varying concentrations of polycyclic aromatic hydrocarbons (PAHs) in sediments from the Estuary and Gulf of St. Lawrence, with higher levels in areas affected by anthropogenic activities. Source-diagnostic PAH ratios indicated a predominance of pyrogenic sources via atmospheric deposition. The PAH concentrations in the study areas suggest low ecological risks to organisms near the water-sediment interface.
MARINE POLLUTION BULLETIN
(2022)
Article
Biodiversity Conservation
Michael L. Zettler, Falk Pollehne
Summary: In 2015, we examined the macrozoobenthic community composition in the deep trough of the Gulf of St. Lawrence, Canada, along a dissolved oxygen gradient. Our findings showed that the dominant communities shifted from molluscs to polychaetes as oxygen saturation decreased. Surprisingly, the estuary stations with the lowest oxygen saturation levels had the highest species diversity, density, and biomass. Key genera in the hypoxic zone included bivalves, cumaceans, amphipods, and polychaetes. Our study suggests that the stability of environmental conditions and the constant supply of oxygen, even at low concentrations, play a crucial role in shaping community composition.
Article
Fisheries
Leopold Ghinter, Christophe Anderson, Dominique Robert, Gesche Winkler, Louis Bernatchez, Celine Audet
Summary: Knowledge of the larval ecology of winter-spawning fish from the Estuary and Gulf of St. Lawrence, Canada, remains scarce due to the seasonal ice cover. However, a recent investigation captured 10 halibut larvae, suggesting that the spawning grounds are located close to the capture sites. This effort is an important step in validating the putative spawning areas for the Atlantic halibut and Greenland halibut, which support the most important groundfish fisheries in the area.
JOURNAL OF FISH BIOLOGY
(2023)
Article
Ecology
Mathilde Jutras, Alfonso Mucci, Gwenalle Chaillou, William A. Nesbitt, Douglas W. R. Wallace
Summary: Persistent hypoxic bottom waters have developed in the Lower St Lawrence Estuary, impacting fish and benthic species distributions. The minimum dissolved oxygen concentrations have decreased over time, while bottom-water temperatures have progressively increased. The change in circulation pattern in the western North Atlantic, specifically the decrease in well-oxygenated Labrador Current Waters, is the main driver of deoxygenation and warming in the bottom waters. The hypoxic zone has expanded in the LSLE and now extends into the western Gulf of St Lawrence.
Article
Environmental Sciences
Gwyneth A. MacMillan, Marc Amyot, Pierre-Yves Daoust, Melanie Lemire
Summary: In this study, we measured trace elements and mercury distribution in grey seals from the Gulf of St. Lawrence, Canada, and found a bioaccumulation pattern in different age groups. The concentrations of elements were lower in the muscles and livers of young-of-the-year seals compared to older ones feeding at sea. There were no significant sex-specific differences, but some elements showed higher concentrations in male seals.
Article
Acoustics
Romina A. S. Gehrmann, David R. Barclay, Hansen Johnson, Najeem Shajahan, Veronique Nolet, Kimberley T. A. Davies
Summary: This study conducted a two-month-long measurement of ambient sound level in the Gulf of St. Lawrence using a glider. The results showed the presence of a sound channel in the Honguedo Strait and provided valuable insights for passive acoustic monitoring and marine mammal detection.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2023)
Article
Environmental Sciences
Duc Huy Dang, Wei Wang, Gesche Winkler, Anique Chatzis
Summary: The study finds significant correlations between the accumulation of rare earth elements (REEs) and other elements in plankton, suggesting non-selective uptake of REEs into plankton. Furthermore, there are differences in the distribution of REEs between freshwater and marine environments, with freshwater plankton exhibiting enrichment of middle rare earth elements (MREEs) and marine plankton showing enrichment of light rare earth elements (LREEs). This study emphasizes the significant enrichment of REEs in freshwater primary producers and their accumulation pathway similar to other inorganic elements.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Diane Lavoie, Nicolas Lambert, Michel Starr, Joel Chasse, Olivier Riche, Yvonnick Le Clainche, Kumiko Azetsu-Scott, Bechir Bejaoui, James R. Christian, Denis Gilbert
Summary: This paper provides a detailed description and analysis of the coupled physical-biogeochemical model of the Gulf of St. Lawrence, with a focus on the microbial loop and riverine contributions. The model successfully reproduces key features of the system, such as phytoplankton bloom and hypoxic areas.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
David Levesque, Michel Lebeuf, Domynick Maltais, Caroline Anderson, Michel Starr
Summary: The role of organic matter inputs has been recognized as an important factor in understanding the issue of hypoxia, which is a worldwide expanding problem in estuaries and shelves due to eutrophication. This study investigated the transport and exchange of particulate and dissolved organic matter in the St. Lawrence Estuary, revealing the significance of organic matter in hypoxia.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Engineering, Environmental
Abigaelle Dalpe Castilloux, Magali Houde, Andree Gendron, Amila De Silva, Youssouf Djibril Soubaneh, Zhe Lu
Summary: The study on the St. Lawrence River showed that BHTQ was the dominant contaminant in dissolved water, and sediment had higher sorption capacities for most target contaminants compared to SPM. Different contamination profiles were found in lake sturgeon and northern pike, indicating that the accumulation of UVAs and IAs in fish depends on their feeding behavior.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Marine & Freshwater Biology
K. A. Sorochan, C. E. Brennan, S. Plourde, C. L. Johnson
Summary: The spatial distribution of zooplankton in the southern Gulf of St. Lawrence is influenced by complex interactions among population dynamics, vertical positioning, and advection. The study revealed distinct horizontal distributions of different copepod taxa, highlighting the importance of interspecific differences in life history strategy and interaction with ocean circulation. These findings have significant implications for understanding the ecosystem and food web dynamics of zooplankton.
JOURNAL OF PLANKTON RESEARCH
(2021)
