Aller directement au contenu.

Rendez-vous St. Lawrence 2021

Program and Hyperlink to the webinar

Webinar 1: 2019 Overview of the State of the St. Lawrence River and Major Issues

Hyperlink to the webinar (In French only)External link

The St. Lawrence is improving; should we celebrate or be cautious? – Nadine Kadri, ECCC

Updated every five years by the Monitoring the State of the St. Lawrence River working group, the Overview of the State of the St. Lawrence provides a diagnosis of the state of the river. Highlights of the 2019 edition will be presented.

State of the St. Lawrence Monitoring Program: The time challenge! – Caroline Anderson, MELCC

The St. Lawrence Rendez-vous is an opportunity to explore ways to improve the State of the St. Lawrence Monitoring Program (SSLMP). While the 2013 and 2016 editions focused on the challenge of integrating information and using synthetic indicators, the 2021 edition will centre on representing temporal trends, indicator measurements that change over time, and emerging indicators.

St. Lawrence issue: The contribution of river inputs of nutrients and organic matter to the acidification of the Estuary and Gulf of St. Lawrence – Michel Starr, MPO

Ocean acidification (OA) is a new threat to the health of aquatic ecosystems. Although OA is a global process associated with the increase in atmospheric CO2, this phenomenon is greatly amplified in the Estuary and Gulf of St. Lawrence. This presentation will take stock of the state of acidification in the Estuary and Gulf of St. Lawrence and its consequences on the ecosystem, as well as on the causes of the amplification of this phenomenon in our coastal waters, and notably on the contribution of river inputs of nutrients and organic matter.

St. Lawrence Challenge: microplastics/macroproblems – Cécilia Mélé, Stratégies Saint-Laurent

Stratégies Saint-Laurent presents the St. Lawrence Challenge, a program aimed at reducing plastic consumption. Program members are committed to taking simple awareness and engagement measures to lessen their environmental footprint. The St. Lawrence Challenge is intended for any organization wishing to take action to preserve the biodiversity of the St. Lawrence, which is affected by the issue of microplastics.

Webinar 2: Environmental Contamination

Hyperlink to the webinar (In French only)External link

Contamination of river water by toxic chemicals – Myriame Lafrance, ECCC

Over the past century, urbanization, industrial and agricultural activities have generated a significant load of toxic substances that have found their way into waterways. Metals, nutrients, pesticides as well as other emerging contaminants (e.g.,: PBDEs) are detected in water at concentrations that can be concerning. Four monitoring stations are used to assess the state of the St. Lawrence river water quality. The majority of contaminants are found at stable or low concentrations (only copper is of concern) and flame retardants (PBDEs) have been steadily decreasing since 2010.

Water quality in the Richelieu and Yamaska rivers – Contamination by toxic chemicals – Denis Laliberté, MELCC

Measurements of trace amounts of contaminants in raw water at two water treatment facilities are used to track temporal changes in concentrations of PCBs, PAHs, PCDD/Fs and PBDEs in the waters of the Richelieu River at Sorel-Tracy and the Yamaska River at St-Hyacinthe, for the period of 2001-2019.

Toxic chemicals in St. Lawrence River sediment – Magella Pelletier, ECCC

Toxic substances from industrial and urban effluents have greatly contaminated the sediments of the St. Lawrence since the early 1900s. Mercury, PCBs, PAHs, dioxins and furans are still present in the sediments of some areas of the river despite all the remediation measures taken by the various governments. Nowadays, new contaminants, mainly from urban effluents, are being added to the list of substances of concern for aquatic life. Sediment monitoring and surveillance are excellent screening tools to maintain the integrity of the St. Lawrence River.

Remediation 2.0, a staging area for improving the health of the St. Lawrence – Jean Paquin, Réseau Environnement

In 2020, Réseau Environnement and Stratégies Saint-Laurent launched the Remediation 2.0 initiative aimed at identifying issues of significance to improve our aquatic ecosystems, modernize our municipal wastewater treatment facilities, and reduce non-point-source agricultural pollution. Significant investments will have to be made in this area in the coming decade, and it is important to ensure that things are done properly. Task forces with specialists from all fields have been invited to take part in the discussions. The presentation will provide an overview of the findings and proposed orientations.

Webinar 3: Environmental Contamination (cont’d)

Hyperlink to the webinar (In French only)External link

Freshwater fish contamination by toxic chemicals in the St. Lawrence River – Denis Laliberté, MELCC

Measurements of contaminants like mercury, PCBs, dioxins and furans, and PBDEs in fish, taken at intervals of three to five years, are used to track changes in contamination in the St. Lawrence River from 1995-2019.

Physicochemical and bacteriological freshwater quality in the St. Lawrence River: potential swimming spots and large bodies of water – Caroline Anderson, MELCC

Two indicators monitored by MELCC make it possible to assess the physicochemical and bacteriological quality of the river’s freshwater. Monitoring of potential swimming spots suggests that the water’s bacteriological quality is greatly influenced by discharges of undisinfected wastewater from the Montreal urban agglomeration. Testing of large bodies of water shows a similar picture: fecal coliforms frequently exceed criteria, particularly downstream from Montreal. Although some parameters, such as turbidity, have been deteriorating since the 1990s, others, like phosphorus, appear to be improving.

Oceanographic processes: temperature, dissolved oxygen, and acidification – Peter Galbraith, DFO

An indicator summarizes the physical and chemical conditions of the Gulf of St. Lawrence and Estuary. For the Gulf, it describes the temperature of the three layers: surface layer, cold intermediate layer, and deep layer, as well as the winter sea ice conditions. For the Estuary, the hypoxic conditions of the deep waters are described as well as its acidity.

Characterization of nearshore waters of the St. Lawrence River – Sophie Lacoursière, Les Deux Rives ZIP Committee

This project to characterize the nearshore waters of the St. Lawrence River is aimed at addressing the problem of a lack of available data on water quality along the river’s shorelines. The project’s objective is to identify the sources and dynamics of pollutants stemming from tributaries and shoreline cities in shallow waters, as well as the development of safe access to the river for recreational purposes.

Webinar 4: Freshwater Biological Resources

Hyperlink to the webinar (In French only)External link

Composition of freshwater wetlands – Guy Létourneau and Martin Jean, ECCC

The surface area of freshwater wetlands indicator was modified in 2014 to incorporate four components: direct anthropogenic pressure on the surface area; the internal dynamics of wetlands; the diversity of wetland habitats; and the protection of wetlands from external stresses. The Boucherville Islands and Lake Saint-Pierre sectors were studied from the 1970s to 2019. The most recent general state and trend of the wetlands in those sectors will be presented.

Benthic macroinvertebrate communities of the St. Lawrence River and the influence of agricultural pollutants – Andrée Gendron, ECCC

Benthic macroinvertebrates – insects, molluscs and worms inhabiting the bottom of lakes and rivers – can be used to determine whether environmental conditions are good or show signs of disturbance. According to biomonitoring studies conducted by Environment and Climate Change Canada scientists between 2004 and 2018, the status of the benthic macroinvertebrate communities in the St. Lawrence River ranged from moderate to poor, with an upstream-downstream gradient of increasing degradation between Lake St. François and Lake St. Pierre. In that latter lake, most riparian macroinvertebrate communities had the characteristics of communities exposed to pesticides.

Monitoring of exotic invasive plants in St. Lawrence wetlands – Yann Arlen-Pouliot, MELCC

The St. Lawrence wetlands EIP monitoring network aims to present a picture of the distribution and abundance of key EIP species and track their evolution over time. Carried out in conjunction with the communities (primarily ZIP committees), this monitoring network extends from the U.S. border to the marine estuary and involves the following EIPs: reed canary grass, flowering rush, water chestnut, European frog-bit, Eurasian milfoil, Japanese knotweed, common reed, and purple loosestrife. Data collected from 2008 to 2014 show medium invasion level for most sectors, except the Montreal sector, where the invasion level is high. During that period, the abundance index remained stable overall for each EIP and each sector. Only the common reed saw its abundance index rise sharply in the wetlands studied. Purple loosestrife is the most commonly observed EIP, while reed canary grass has the highest abundance index.

Habitat connectivity in Lac Saint-Pierre – Louise Corriveau, Lac Saint-Pierre ZIP Committee

Habitat connectivity is a significant issue. The shores of Lac Saint-Pierre flood annually, and hundreds of rivers empty into it. A number of obstacles impede the circulation of aquatic wildlife and prevent reproduction. It is possible for anthropogenic activities and wildlife to coexist—here are a few solutions.

Webinar 5: Freshwater and Marine Biological Resources

Hyperlink to the webinar (In French only)External link

Monitoring of invasive freshwater animal species – Olivier Morissette, MFFP

The presence of exotic invasive species is a major threat to the biodiversity and biotic integrity of ecosystems. Recent decades have been marked by a global acceleration in the rate of introduction of invasive aquatic species, and Quebec has been no exception. This presentation will provide a historic and current picture of the situation of invasive aquatic species in Quebec, particularly in the St. Lawrence, and will address perspectives in combatting invasive aquatic species.

Monitoring of the St. Lawrence River striped bass population – Éliane Valiquette, MFFP

Nearly 20 years after its reintroduction into the St. Lawrence River, the striped bass is gradually recolonizing the St. Lawrence ecosystem. To date, the species has proven to be resilient, and the latest monitoring results are encouraging. There are now two known spawning areas, and various indicators suggest that the population is on the road to recovery.

Status of fish communities in the fresh and brackish waters of the St. Lawrence – Yves Paradis, MFFP

More than 80 species of fish frequent the fresh and brackish waters of the St. Lawrence River, and assessing the status of these fish stocks is a complex undertaking. This presentation provides a current picture of the state of knowledge of fish communities and aquatic habitats in the St. Lawrence in order to assess changes in these components over the past 25 years. Analyses of the various indicators yield sometimes divergent findings among the different species and sectors.

Status of the great blue heron population – SLAP issues and next steps – Philippe Thomas, ECCC

The study of great blue heron populations at two sites in the St-Lawrence has provided evidence that many of the monitored contaminant classes have been declining in their eggs since 1991. In order to increase both spatial and temporal coverage of this biomonitoring program, a new inclusive approach with many Innu Nations of Quebec is proposed. A new indicator, the herring gull, is suggested so that links can be established between the state of the St Lawrence, the state of the Great Lakes, and the state of human health in those Indigenous communities that so closely depend on healthy ecosystems.

Webinar 6: Biological resources in marine waters

Hyperlink to the webinar (In French only)External link

Monitoring of the St. Lawrence Estuary and Gulf phytoplankton, toxic algae and zooplankton communities – Marjolaine Blais and Michel Starr, DFO

Twenty-year monitoring of the St. Lawrence Estuary and Gulf phytoplankton and zooplankton communities shows that their overall state was stable over the 2013-2017 period. Phytoplankton biomass and composition were highly variable but they did not show any strong anomalies over this period. However, zooplankton biomass has diminished over the same period and zooplankton community composition is changing, with possible impact on the food web. The frequency of toxic algal bloom has been lower over the period 2014-2017 than during the previous 5-year period. This presentation will also provide an update of these index based on the most recent data available (2018-2019).

Marine birds as indicators of the ecosystem of the Gulf of St. Lawrence – Jean-François Rail, ECCC

The population dynamics of seabirds are the reflection of the integrity and health of the St. Lawrence marine ecosystem. Both the assessment of the population trends in five seabird species breeding along the North Shore of the Gulf of St. Lawrence, and the analysis of the situation of the Northern Gannet in Quebec, lead to conclude that the status of these indicators is actually “moderate”. In the first case the situation remains unchanged, in the latter this represents a slight improvement since the last quinquennial assessment.

Status of the beluga population – Véronique Lesage, DFO/PCA

The St. Lawrence Estuary beluga is a population considered endangered in Canada, and which has been declining over the past 20 years. Multiple climatic and/or anthropogenic threats have been identified and could be at play. These threats will be presented.

Targeted action to combat the establishment and spread of an invasive tunicate, the vase tunicate – Aglaé Poirier, ZIP des Îles-de-la-Madeleine

The vase tunicate first appeared in the Magdalen Islands in 2006. Through annual monitoring, the DFO observed in 2013 that the numbers had become particularly worrisome. These observations were confirmed during exploratory dives. A number of local stakeholders, such as the Comité ZIP des Îles, undertook a project to clean the Cap-aux-Meules wharves and prevent the vase tunicate from spreading through the archipelago. The presentation focuses on the various techniques used during these interventions and on the project’s results. An update on the status of vase tunicate populations in the Magdalen Islands and an overview of current and future efforts by Comité ZIP des Îles to combat this invasive aquatic species will also be presented.