Lampricide Treatment on the Credit River

Credit Valley Conservation (CVC) would like to advise that today, Fisheries and Oceans Canada (DFO) began treating approximately 61 km of the Credit River between Cheltenham and Lake Ontario with lampricide TFM (3-Trifluoromethyl-4-nitrophenol) to reduce the resident larval Sea lamprey population.

Lampricide will be applied for approximately 14 hours from Norval to Port Credit. It will take several days to reach Lake Ontario. The river may appear yellowy-green during treatment.

Lampricide selectively kills Sea lamprey larvae but may also result in the death of other fish that are weakened by disease, spawning or other environmental factors. Although lampricide is not harmful to humans or other animals at the areas during treatment, any use of stream water for irrigation and drinking is not recommended for a 24-hour period during the treatment.

The Sea lamprey is an invasive species in the Great Lakes. Since the 1950’s, DFO’s Sea Lamprey Control Centre has worked under an international agreement with the Great Lakes Fishery Commission toward the delivery of effective Sea lamprey control in the Great Lakes.

For more information, contact Theresa Nichols, Fisheries and Oceans Canada, at 204-983-0600 or [email protected].

Last lampricide treatment in 2011

Conservation Authorities are a provincial/municipal partnership. CVC was established by an Act of the Province of Ontario in 1954 with a mandate to protect all natural resources, other than minerals, in the area drained by the CreditRiver. We have been working for 60 years with our partner municipalities and stakeholders to protect and enhance the natural environment of the CreditRiver watershed for present and future generations. CVC is a member of Conservation Ontario.


Media Contact:
Baljit Sharma
Marketing & Communications Specialist
Credit Valley Conservation
905-670-1615 ext. 224
[email protected] 

Information Contact:
Theresa Nichols
Fisheries and Oceans Canada
[email protected]

Jon Clayton
Aquatic Biologist
Credit Valley Conservation
905-670-1615 ext. 502
[email protected]

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