Few of the hundreds of thousands of Chinook salmon introduced into Lake Ontario each year survive to maturity, but the Ministry of Natural Resources is still betting on them to help to improve the health of the Great Lakes.
THERE WAS A GENERAL SENSE of anticipation when the Ministry of Natural Resources truck backed in next to the Snug Harbour marina in Port Credit in Mississauga, Ontario. Everyone there at the water’s edge knew how important the truck’s cargo was to the overall health of the silty Credit River flowing brown into the lake.
Roughly 100 people gathered on a sunny Saturday in early April, through the efforts of the Port Credit Salmon and Trout Association and the Ministry of Natural Resources, to help introduce 10,000 Chinook salmon fingerlings into a nine-by-four foot pen tucked between boat slips.
Brian Lambie, president of the Port Credit Salmon and Trout Association, showed me around the floating docks at Snug Harbour before crowds of children and adults would begin carrying buckets of fish in a fire-brigade fashion along the docks to the pen.
City Councillor Jim Tovey and Ontario Finance Minister Charles Sousa, the MPP for Mississauga South, emptied the first ceremonial bucket of fish into the pen as crowded onlookers jostled for photos and a better view while making sure no one fell off the narrow docks and had to be fished out.
For the next month, the fingerlings will remain here as they go through a kind of puberty called “imprinting,” Lambie said, and begin to associate the Credit River as their home.
Until the fish are released, they’ll be wards of the City of Mississauga with municipal staff checking in and feeding them. After their time in Snug Harbour is up and an indelible imprint of the Credit River etched in their brains, the fish will head out into the lake where it’s hoped they’ll grow to upwards of 30 pounds before returning to this river in four years to spawn.
It’s a victory-through-sheer-volume approach. The Ministry of Natural Resources and organizations like Lambie’s help introduce over 700,000 Chinook salmon every year to Lake Ontario with more than 100,000 released into the Credit River alone in 2013. This is on top of other fish species MNR helps re-stock in the Great Lakes like once-native Atlantic salmon.
Snug Harbour is just one of eight net pens located on the shores of Lake Ontario: Port Dalhousie, Bluffers Park in Scarborough, Whitby, Oshawa, Darlington, Brighton and Wellington house the others.
But before anyone thinks Lake Ontario is swarming with salmon, the survival rate of these tiny fingerlings, no more than two inches long when interred in the pen, hovers around one per cent. Three per cent in a good year. It’s sobering to think if only 100 of these 10,000 fish survive to maturity conservationists and government biologists will be pleased. If 300 make it they’ll pop champagne.
Stocking Lake Ontario via regional pens doesn’t always work out as planned, however. In 2013, a fierce cold snap hit southern Ontario weeks after the ministry released their hatchlings for the year. The entire stock was lost right across the province.
But MNR carries on. Between the weather, native predators like birds and larger fish, human impairments to settlement like dams and pollution, the odds are stacked against the overwhelming majority of fingerlings released this month, and the ministry knows it, Lambie said.