Invasive Grass Carp Found on Toronto’s Waterfront

Two Asian Grass Carp have been found within a contained pond in Tommy Thompson Park along Toronto’s Waterfront. Toronto and Region Conservation (TRCA) staff discovered the first live Grass Carp Monday, July 27 while relocating fish from the pond as part of the construction of a nine hectare wetland.

The second Grass Carp was found in an isolated section of the same pond Tuesday, July 28 as part of a collaborative search effort by TRCA, Ontario Ministry of Natural Resources and Forestry, and Fisheries and Oceans Canada. As with the first discovery, the second Grass Carp was immediately sent to a Fisheries and Oceans Canada laboratory in Burlington for further investigation.

Grass Carp is one of several species in a group of fish known as Asian Carp. They are native to Eastern Asia and have been used in North America, primarily as a food source and also as a means for managing aquatic vegetation. Where they have proliferated in parts of the United States, Grass Carp have had a negative effect on the ecosystem, as well as on the commercial and recreational fishery. Grass Carp feed extensively on aquatic vegetation, often uprooting large areas of vegetation, thus depleting other native fish species. Grass Carp differ from the Common Carp found in Lake Ontario which were introduced to Ontario in the 1800’s.

In recent decades, TRCA has worked to monitor and restore fish habitats along Toronto’s waterfront and the watersheds that feed into it, restoring significant populations of native fish species that were decimated as the Toronto urban region grew. With the expansion of wetlands, improvements to shorelines, including the installation of fish habitats along the waterfront, pike, walleye and bass populations have flourished. Last year, TRCA worked on 175 restoration projects – Tommy Thompson Park, where the Grass Carp was found is one of the most significant.

The only other live Grass Carp in a Toronto waterway was found by TRCA staff in 2003 at the mouth of the Don River. TRCA continues to work in the field and on the water in cooperation with Fisheries and Oceans Canada, the Ontario Ministry of Natural Resources and Forestry, and other agencies engaged in the protection of the Toronto region waterways from damaging invasive species.

See also 2 Asian carp found in ponds near Toronto waterfront, Notoriously invasive Asian carp found in Toronto and 2 Asian carp, considered highly invasive, found in Toronto pond.