Grondines swamp, freshwater estuary, St. Lawrence River (photo by Claude Duchaîne)

Grondines swamp, freshwater estuary, St. Lawrence River (photo by Claude Duchaîne)

The Grondines Swamp

Silver maple stands, Grondines (Photo by NCC)

Silver maple stands, Grondines (Photo by NCC)

A unique ecosystem

The Grondines swamp, which extends along seven kilometres of shoreline in the Saint Lawrence River’s freshwater estuary, is one of the last large-area treed swamps on the river.

It shelters several at-risk species, including plants that are endemic to the freshwater estuary, making it a rare biodiversity hot spot on a global scale, according to the Atlas de la biodiversité du Québec (Quebec biodiversity atlas). Indeed, preserving this intertidal zone helps protect numerous colonies of Victorin’s water-hemlock and Parker’s pipewort, two plants designated as threatened under the Quebec Act Respecting Threatened or Vulnerable Species (ARTVS) that are found exclusively in the Saint Lawrence River’s estuary and that contribute to making the Grondines swamp unique. The 90 acres (36.5 hectares) protected by NCC includes a large floodplain forest and an intertidal zone, a portion of which is officially designated as a Waterfowl Gathering Area (WGA). The diversity and number of birds that frequent the area’s agricultural, forest and coastal lands are impressive, with over 100 species recorded in the area.

The restoration project

NCC has been helping conserve this exceptional environment since 2008 and is currently conducting a restoration and enhancement project here. An area of fallow land within a protected property will be returned to a natural environment that respects the unique ecological integrity of the area. In two years, 2,500 trees have been planted on the edge of newly developed basins to promote biodiversity. Silver maple, butternut, red ash, common elderberry, balsam poplar, eastern cottonwood, dogwood and cranberry viburnum are some of the indigenous plants that have been used to reforest this exceptional natural environment. The project also aims to raise awareness among the local community about the richness of this environment and the variety of actions that can be implemented to protect it.


NCC has been able to protect the 90 acres (36.5 hectares) of the Grondines swamp thanks to the generous contributions of the Government of Canada, through the Natural Areas Conservation Program, the Fondation de la faune du Québec, the Quebec Ministère du Développement durable, de l’Environnement et des Parcs, the Earth Rangers program, the U. S. Fish and Wildlife Service and private donors.

The restoration work is made possible by financial support from the Fondation Hydro Québec pour l’environnement, with the participation of Environment and Climate Change Canada and the U. S. Fish and Wildlife Service, as well as the Alcoa Sustainable Communities Fund.

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