The Round Goby, an invasive fish species, was detected in the upper reaches of the WestCreditRiver, near the village of Hillsburgh. The discovery was made by CVC’s watershed monitoring crew in late August of 2013.

The Round Goby was introduced from Europe and has spread throughout the Great Lakes. It’s not known how long they’ve been in the West Credit or how they arrived, but it’s suspected that they’ve been in two ponds and connecting stream for at least a year. Their current range appears to be restricted to the Hillsburgh area, but there’s risk they can migrate downstream.

Round Goby by Jon Clayton

The West Credit River offers cold-water stream habitat, vital for sensitive Brook Trout populations. Round Gobies are another threat to this declining population. Should Round Gobies move downstream and into the Credit River, they may out-compete the native benthic species, impact the stream insect community, the restoration of Atlantic Salmon and the Rainbow (steelhead) Trout populations that offer important urban angling opportunities. The broadest concern is to the more diverse and productive warmwater fisheries of the Credit along the main river and other animals dependent on the benthic insects that form the base of our food web.

Previous monitoring in the Credit River watershed showed that the invasive fish was localized along the Lake Ontario shoreline and the lower reaches of the Credit River in Mississauga.

Round Goby by Eric Engbretson, US Fish and Wildlife Service,
Round Goby by Eric Engbretson, US Fish and Wildlife Service,

MNR and CVC have taken action to prevent the further spread of Round Goby by containing the areas where they were found. Containment measures provide time to plan long-term management actions that could include the goal of eradicating round goby from the WestCreditRiver. MNR and CVC, with input from landowners and local stakeholder groups, are working to determining further management approaches.

Anglers are reminded that the Ontario government has banned the possession of live Round Goby and their use as baitfish. It’s illegal to dump the contents of any bait container within 30 metres of any lake, pond, river or stream. You should always carefully dispose of unwanted bait in the trash and empty bait bucket water on dry land.

You can report observed invasive species, like Round Goby, to the Invading Species Hotline
at 1-800-563-7711.

For more information visit,

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