Return of the Salmon: Restocking the Credit River

Forks of the Credit Provincial Park isn’t somewhere you’d expect to stumble across a press conference. Nevertheless, on a wet, cool day last May, several dozen dignitaries, media and students, trucked miles into the park by 4×4, found themselves huddled under umbrellas in the mud, celebrating the return of a long-lost resident.

The Atlantic salmon was home again.

In fact, 44,000 of them had just moved in, spread over a kilometre or two of near-pristine stream bed within the park boundaries.

Chris Robinson, a biologist with the Ontario Federation of Anglers and Hunters, and acknowledged Atlantic salmon guru, says, “Atlantic Salmon have been absent from this native habitat since the late 1800s, when over-fishing and other human environmental impacts resulted in their decline and eventual local extinction.”

A new $4-million-plus program is seeking to re-establish the species in not only the Credit River, but also Duffins Creek and Cobourg Creek to the east of Toronto.

Atlantic salmon (Salmo salar) are mostly silver, changing to bronze during spawning, and known for their amazing ability to leap upstream and over dams to get to their spawning grounds. The original population in Lake Ontario likely averaged about twenty to thirty-two inches and weighed eight to twelve pounds. Though there are catch records of fish up to forty-five pounds.

While most Atlantic salmon populations are sea-running, it is not uncommon for them to be landlocked, like those in Lake Ontario. The lake population adapted to life in freshwater conditions after arriving there from the sea about 10,000 years ago. After spending two or more years in rivers where they hatched, smolts would move on to spend adulthood in the lake.

Unlike many other salmon species, Atlantic salmon survive spawning and go back to the lake to do it all over again. Like other species, they always return to the same river in which they were born.

Lake Ontario Atlantic Salmon were a very important resource to the aboriginal peoples, both as part of their diet and as an object of worship. When European settlers first arrived here, salmon populations were so large that in 1839, one fisherman wrote “two persons in a canoe with a spear and a torch would sometimes kill eight to ten barrels of salmon in one night.” The commercial and recreational fishery that soon developed at one time supported thousands of workers.

The impact of this industry was only one factor that led to serious declines in the stock. Deforestation for agriculture meant not only a loss of cover for breeding sites, but also massive erosion and silt problems, damaging spawning beds. The salmon’s traditional prey in Lake Ontario was also affected, making food scarce.

By the mid-1800s Atlantic salmon had become one of the first species in Canada to be decimated by the actions of human beings. In 1850 there were eighty-seven dams on the Credit River watershed, including nineteen in Caledon and Erin. Even for the athletic salmon, these created an insurmountable barrier.

The first attempt to restore the population in 1866 met with some initial success, but by 1872, a spawning survey indicated that the fish were absent from the watershed. The species was officially declared extirpated in Lake Ontario in 1896.

During the 1940s the provincial government tried again, but after five years of stocking with little success, efforts were stopped. Other attempts were made, but in 1964 it was decided the entire ecosystem was too damaged for restoration to occur.

Stream stewardship and habitat maintenance, including significantly improved sewage management, have come a long way since the 1960s, and overall conditions have improved substantially. In Caledon, for instance, the forest cover has returned to about 25 per cent of the town’s total area.

By the late 1980s, the province had once more taken up the salmon’s plight. In 1995, it began a small-scale stocking program for research purposes. In 2003, armed with positive results, it was time to consider full-scale restoration. Action plans were developed to seek funding and partners, expand fish-rearing capabilities and create research and assessment tools, so that progress could be measured.

The result was the creation of the Lake Ontario Atlantic Salmon Restoration Program, also known as Bring Back the Salmon, an impressive public/private initiative that includes nine major partners and sponsors.

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There are three primary components to the program: fish production, habitat restoration and monitoring/assessment.

If a self-sustaining population is to be developed, a large number of salmon must be stocked. Chris Robinson anticipates that “only about one in a thousand spring fry will survive to reach adulthood and return to spawn. For those released in the fall, who are a few months older and bigger, the survival rate may be in the order of one in five hundred.”

Yearlings, to be released for the first time this year, are expected to have an even higher survival rate.

One of the challenges the program faces is simply producing enough fry. Mark Heaton, a fish and wildlife biologist with the Ontario Ministry of Natural Resources, explains the network that has been developed to rear fry. “There are four levels to the system” he says. “First, there are three large hatcheries in the province, two of which are operated by MNR. The Harwood Fish Culture Station has all the broodstock.”

The other two main hatcheries receive eggs and develop them to various life stages for release. In 2006, the ministry produced 400,000 fry for the overall program, though there are plans to upgrade facilities and expand beyond that.

“The second level,” Heaton continues, “would be the medium-sized hatchery run by Sir Sanford Fleming College as part of its co-op program. Then there are several smaller satellites, often run by community groups or volunteers.”

One of those small hatcheries is in Belfountain where Heaton lives. In addition to his MNR duties, he is an active volunteer at the village’s hatchery.

The final level is “micro-hatcheries,” located in elementary schools. The program, initiated about five years ago, currently operates in twenty-one schools provincially, eight of which are in Peel, including Alton and Belfountain. The Belfountain school hatchery is one component of its extensive outdoor education program, supported in part by the Town of Caledon’s Community Green Fund.

The micro-hatcheries include incubation equipment and 100 eggs for each classroom. “Students collect data on survival rates to hatch, first-feed and stocking date,” says Heaton. “They’re also invited when the fish are released in Forks of the Credit Park.” Later, they participate in stream studies designed to measure the density of salmon in the river, comparing specific sites to determine which are better.

The salmon restoration program is also exploring alternative methods for producing fry and yearlings, including in-stream or streamside incubators. Says Robinson, “We will continue to aggressively stock for five years until the first ones begin to return, and then monitor their natural performance.”

Though this is the first time in recent years that such a large-scale restoration effort has been attempted, some Atlantic salmon restocking has been underway in the Credit River for nearly a decade. Local residents came together to establish the Belfountain Hatchery in 1997.

Located along the banks of the West Credit on private property belonging to one of the members, the community hatchery has gradually evolved. Initially a simple up-welling box used to raise salmon fry, it has grown into a carefully designed and regulated system. Though it has received some outside financial assistance, the hatchery is mostly supported by local fundraising, including a community music festival.

Water is collected from springs as it emerges from the stream bank. “Collecting it right at the spring limits the potential for contamination,” Heaton says. From there, it is pumped 120 metres across the river to a large reservoir, which supplies the hatchery itself, located in a small, heated shed.

Inside, thousands of tiny fry huddle together in plastic bins. Thousands more eggs, many with black dots where their eyes are developing, are stacked in trays. Water can be heard trickling through the system, and regulating its temperature also regulates the rate of growth for the fish, allowing a measure of control.

Bigger fish, some as long as eight inches, occupy large blue plastic tanks. Because of the salmon’s ability to leap, Heaton says, “We have to keep nets on the top of the big tanks, or they’d all be on the floor by morning.”

While overall ecosystem quality has improved in recent years, habitat restoration will nonetheless be a critical component of the provincial program. Over the first five years, trees are being planted and other bank stabilization measures taken to minimize sedimentation of spawning areas and help control water temperature. Debris is being removed from the riverbeds to restore natural flows, and steps taken to ensure a high quality and quantity of water through wetland protection. Cattle fencing and alteration to dams and ponds to permit fish passage are other examples of habitat restoration projects.

Concerns that salmon restocking might displace rainbow, brook and brown trout are offset by research indicating that if habitat is available, both species can thrive. In addition, upper reaches and areas with large trout populations have been avoided.

The final component of the program, research and assessment, will provide critical information about survival rates and reproductive success of fish stocked at various life stages, as well as information about ecosystem health. This will allow the program to adapt as it moves forward. Information collected through the school program is a valuable element of the database.

Now entering its second year of operation, the Bring Back the Salmon program counts its first year a success. “Between stocking and habitat work, 237 volunteers contributed over 1,100 hours of time,” Robinson says. In addition to the initial 44,000 spring fry, “50,000 fall fingerlings went into the Credit from October 31 to November 2. About 25,000 yearlings will go in this April, and then we start another round of fry stocking in May.”

Fall fish surveys found high and very high densities of Atlantics in the spring stocking sites along the Credit. Says Robinson, “Their growth rates were also impressive. The wild fingerlings were on average larger than their siblings still in the hatchery. The Credit River in particular had very high growth rates, an indication of the productivity of the system.”

Heaton notes that provincial legislation that protects the Greenbelt, the Oak Ridges Moraine and the Niagara Escarpment contributes to positive long-term prospects for the salmon.

Broodstock can now be adopted through the “Adopt an Atlantic” fundraising program. For ten dollars, participants receive a certificate and the opportunity to name a fish. You and your fish are listed on an Adoption Registry on the program web site, at www.bringbackthesalmon.ca.