Although one would expect to see a goldfish as a pet in a bowl, some feral goldfish are also being found in retention ponds in Saskatoon.
Once goldfish are released, they become darker in colour, and they start to grow. According to Matt Tyree, fisheries unit manager with the Ministry of Environment, released goldfish have been found to grow up to three and a half pounds.
Tyree says goldfish, as well as other species of fish, can show up in city ponds in one of two ways: intentionally, by being released, or unintentionally, by flooding from a garden pond. Once in the city’s waterways, goldfish can become invasive.
“These species often can out-compete our native species,” he said. “They can occupy habitats that are required for our native species. They can consume their food. They can also carry disease with them as well.”
There’s also a provincial task force for preventing the spread of invasive species, which includes representation from both governmental and non-governmental organizations. The task force also partners with universities.
“We’ve drastically increased our provincial programming related to aquatic invasive species protection,” Tyree said. “We’ve done a lot over the last couple of years to strengthen our regulations related to aquatic invasive species.”
This summer, University of Regina researchers found a few goldfish in a pond in the Briarwood neighbourhood in Saskatoon. The research is currently still in its infancy, but will go more in depth in the summer of 2019.
