Biologist Pierre Dumont has lived in Montreal and worked in the waters surrounding the island for most of his career, yet much about the St. Lawrence Seaway is still shrouded in mystery for him. He specializes in marine wildlife in the St. Lawrence Lowlands, including the copper redhorse, an endangered fish that lives only in Quebec.

Its spawning grounds are the waters south of the Saint-Ours Dam, which it reaches via a route that starts at the mouth of the St. Lawrence, goes south into the Richelieu River and then through a fish ladder — a structure of step-like pools that helps fish bypass dams — built in 2001.

“We don’t know if they take this route every year or every two years, but let’s say I’m [a 10 or 12-year-old copper redhorse], I swim down the fleuve and get to Sorel. What makes me do that? I don’t know. I’d like to be a fish sometimes to figure it out,” Dumont said.

Another biologist, Alain Branchaud, describes the copper redhorse as a typical Québécois, wavering between national holidays. “It hesitates between June 24 and July 1 to reproduce. … If it’s warmer, it will spawn on Saint-Jean-Baptiste [Day]. If the water is a bit colder, it will wait until closer to Canada Day,” Branchaud, general manager of SNAP Québec, the province’s chapter of the Canadian Parks and Wilderness Society, said.

After spawning, the copper redhorse might hang around the Richelieu River or loop back to the St. Lawrence where grass beds act as food sources. The unique fish is equipped with molars that can break the shells of mollusks it feeds on in underwater beds of grass, located in areas with a gentle current.

The copper redhorse is endemic to Quebec and has been present in the area for centuries, serving as an important food source for Indigenous Peoples. Its natural habitat and feeding grounds along the St. Lawrence River are threatened by the proposed port expansion, adding it to a list of other at-risk species that could be harmed by the project. Photo: Supplied by SNAP Québec

This pantry, along with the habitats of other at-risk species such as the western chorus frog, would be damaged by the proposed expansion of the Port of Montreal in Contrecoeur, a town of just under 10,000 about 40 kilometres downriver from the city. For years, if not decades, the Montreal Port Authority has been advancing a plan to increase its capacity by 60 per cent. That proposal got a big boost on Sept. 11, when Prime Minister Mark Carney announced the port expansion could be one of five infrastructure projects fast-tracked via a referral to the Major Projects Office created in June, when the government passed the Building Canada Act through Bill C-5. This referral would position the project in the national interest, promising federal review within two years, with any environmental or other conditions coming only after approval.

Preliminary work on land for the new port is set to begin this month, as the port authority waits for a Fisheries and Oceans Canada permit to carry out work in the water. The authority received notice that its application was complete on Aug. 28, and should have an answer by Nov. 28.

The same day Carney unveiled his major project list, the Quebec Environmental Law Centre sued the federal government to challenge the validity of Bill C-5, saying the legislation gives the government excessive powers, which jeopardizes democracy and environmental protection. If the Fisheries and Oceans permit goes through, Branchaud said SNAP Québec also plans to sue the federal government, for violating the Species At Risk Act, since the project infringes on the copper redhorse’s critical habitat. The fish has been included in Quebec’s Loi sur les espèces menacées since 1999, and was listed as endangered under the federal Species At Risk Act in 2007. In 2022, a report from Fisheries and Oceans Canada showed that recovery was possible thanks to efforts including an artificial spawning program — though it hinged on avoiding or mitigating threats to its habitats.

The Port of Montreal is the largest port in Eastern Canada and the port authority has been planning to increase its capacity for years. Proponents argue that recent trade upheaval with the United States makes its expansion urgent. Photo: Christopher Katsarov Luna / The Canadian Press

For its part, the port authority said that, for the time being, given that it is expecting to be granted a Fisheries permit, it doesn’t intend to leverage the Building Canada Act to bypass environmental law. “There is no plan B, there is only a plan A, which is respecting process and the law,” a Montreal Port Authority spokesperson said at a press conference on Oct. 1.

The Contrecoeur expansion would allow for the coming and going of the equivalent of more than one million additional standard-sized shipping containers every year. It’s a $2.3-billion effort to which the federal and provincial governments have committed $150 million and $130 million respectively (sources for the remaining funding are unclear).

But environmental groups like SNAP and some business experts have questioned the need for the expansion altogether, as overflowing docks seen during the later part of the COVID-19 pandemic are a thing of the past and imports are currently dropping. In 2024, 4.8 per cent fewer containers were handled in the Port of Montreal, the largest in Eastern Canada, than in 2023. The argument from Quebec Premier François Legault and other proponents is that increased capacity is needed to diversify markets amid trade upheaval with the United States.

Copper redhorse has seen its habitat altered by humans for centuries, and it is hanging on by a thread

A Montreal scientist and fisherman first brought the copper redhorse to the federal government’s attention in 1942. But the fish was important to Indigenous people of the region long before that. “Since the 1950s, the community’s threshold for cumulative impacts to aboriginal fishing rights on the St. Lawrence River has been breached. Many of the impacts likely to flow from the Contrecoeur project will add to existing impacts on water quality, wetlands, fish and fish habitats,” the Mohawk Council of Kahnawà:ke stated in a letter about the port expansion proposal to the federal agency in charge of environmental assessments in 2019.

The letter said that the Kaniatarowanenne, or St. Lawrence River, has been important to Mohawk “since time immemorial.” Copper redhorse is just one of the foods the river used to provide, the letter said, along with waterfowl, eels, sturgeon, walleye and mussels. Centuries of environmental degradation and development have polluted the St. Lawrence and its tributaries, it said, making fishing and harvesting unsafe and infringing on the constitutional rights of Mohawk people including the residents of Kahnawà:ke, just south of Montreal.

An illustration by artist Ghislain Caron for the label of Rescousse, a beer launched in 1998 to raise funds to protect and support the copper redhorse. Environmental degradation and development in the St. Lawrence River and Montreal area have contributed to the dwindling numbers of copper redhorse. Photo: Supplied by SNAP Québec

None of the three First Nations consulted on the proposal agreed to be interviewed by The Narwhal, but in its letter, the council noted dredging damage to the grass beds that copper redhorse feed from was just one of many concerns Kahnawà:ke had about the project. In June, Kahnawà:ke Grand Chief Cody Diabo went to Ottawa to protest C-5, telling APTN Carney declined his request for a meeting.

Scientists say a confluence of factors likely explain the dwindling numbers of copper redhorse: agriculture that leaks herbicides and pesticides into the water, increased recreational sports in breeding grounds and development. Montreal’s preparations for the Expo 67 world fair saw massive alterations to the landscape, including digging, in-filling and the use of DDT, a pesticide that has since been banned in Canada. Archaeological digs have uncovered remains of the copper redhorse at Indigenous food preparation sites and at an Old Montreal inn, adding fishing to possible stressors.

Branchaud likens this list to being dealt individual blows: one hit might just make you angry, but a second smack might destabilize you and a third could knock you out. “The copper redhorse has received about 123 blows and we can’t afford to give it another,” he said.

In 2021, Fisheries and Oceans Canada gave the Montreal Port Authority a list of 330 conditions required for the expansion to move forward. One was that the port authority compensate for grass beds lost to the project, which the authority plans to double in size. Dredging work that will damage critical copper redhorse habitat is set to begin in 2027, though the port authority says the successful establishment of compensatory grass beds at l’Île aux Boeufs, about 25 kilometres upriver, will come first.

“Over a period of a year and a half to two years, we will be able to develop all the compensatory work to link the copper redhorse to the new grass beds. … We will be keeping an eye on two things: performance and propagation [of the grasses],” Paul Bird, the port authority’s chief commercial officer, said at a press conference in early October.

In a 2021 SNAP Québec report on the impacts of the project on the copper redhorse, four scientists opposing the proposed Contrecoeur expansion said they feared extinction of the fish. They described the project’s negative effects as underestimated and the benefits of compensatory measures as hypothetical at best. The value of replacement fish habitat is questioned elsewhere in Canada, too: in B.C., scientists found a lack of upkeep hinders success.

Construction and dredging of the St. Lawrence would also create sedimentation and disturb contaminants buried deep, including butyltin compounds — endocrine disruptors that could harm the fish’s already difficult reproduction cycle. There are only a few hundred known individuals of the species of redhorse unique to this busy stretch of the St. Lawrence and a few of its tributaries, which Branchaud has been at the forefront of defending. In 1998, he was part of a successful effort to rename the fish from copper sucker to copper redhorse — a rebrand that paid off in increased media attention and fundraising campaigns, like the launch of a beer called Rescousse, or rescue, with the fish on its label.

Branchaud sees the port expansion arriving at a time when the copper redhorse is already on life support. He thinks the proposition to relocate part of its critical habitat is so large it could harm other species while not doing much to protect the endangered fish. At the press conference, a Montreal Port Authority spokesperson said, “We plan on taking action on 0.9 hectares of grass beds, equivalent to a soccer field. The copper redhorse’s habitat is many thousands of hectares.”

Branchaud doesn’t agree with that sentiment. “Imagine that the copper redhorse is a person, and parts of its essential habitat are the heart and brain. Would you accept having a small piece of your heart removed? But don’t worry, we’re going to graft another piece to your back,” he said. … “[The spokesperson] is not a scientist and does not understand these concepts.”

Copper redhorse are rarely encountered in the wild anymore, due to their dwindling numbers. On the left, a researcher holds a fish being studied; on the right, a fisherman shows a wild fish that will be released back into the river. Photos: Supplied by SNAP Québec (left) and Darian Savage (right)

Contrecoeur residents have other concerns about the port expansion, creating the Vigie Citoyenne Port de Contrecoeur/Montérégie group and website. Their quality-of-life worries include the estimated 1,200 heavy trucks that would roll through town on a daily basis, as well as the loss of 20,000 trees and 675 metres of shoreline.

The municipal government has said it wants the project to work out, citing the economic boost. “However, the most important thing at the moment is for the project to be carried out in compliance with rules, without compromising the natural environment and quality of life of Contrecoeur’s residents. We take our role seriously and want to reassure our citizens that the municipality is vigilant,” it told The Narwhal in an email.

Along with protecting the endemic fish to which he has devoted a considerable part of his career, top of mind for Branchaud is how the fast-tracking of this project and others through Bill C-5 could circumvent environmental law, even if the port authority says that option isn’t currently on the table. For the biologist, that would go against the values concretized into law in 2002 with the Species At Risk Act.

“We arrived at this new law that gives us the option to bypass the country’s entire environmental legislative framework that was built over 150 years,” Branchaud said. “The law to build Canada could eventually become the law that destroyed Canada, not only in the literal sense of destroying our natural heritage, but also the democracy we built.”

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