Science Response 2019/040

Review of elements of proponent application to use rotenone for the purpose of eradicating Smallmouth Bass (Micropterus dolomieu) from Miramichi Lake, New Brunswick

Context

Smallmouth Bass (Micropterus dolomieu), a non-native fish species to New Brunswick, was confirmed in 2008 as introduced and established in Miramichi Lake, a headwater lake of the Southwest Miramichi River, of the southern Gulf of St. Lawrence (DFO 2009). A risk assessment concluded that there is a high likelihood of widespread establishment of Smallmouth Bass in the Southwest Miramichi River and in the Gulf Region rivers in general (DFO 2009). Physical barriers were considered to be the most effective immediate measure for containing the spread of Smallmouth Bass out of Miramichi Lake and this was actioned beginning in 2009 (Biron 2018). Control measures included intensive fishing in Miramichi Lake to remove adult and juvenile stages of Smallmouth Bass, which reduced the abundance of Smallmouth Bass but did not eradicate it from the lake (Biron 2018).

A non-government organization has submitted a request to the Minister of Fisheries and Oceans and the Canadian Coast Guard to authorize the deposit of a deleterious substance (rotenone) to eradicate an aquatic invasive species (Smallmouth Bass) in Miramichi Lake, New Brunswick. Pursuant to s. 19(3) of the Aquatic Invasive Species Regulations SOR / 2015-121 (AISR), fish toxicants could be authorized in New Brunswick by the Minister of Fisheries and Oceans to eradicate Smallmouth Bass because it is not an indigenous fish species to the Maritime provinces.

The Aquatic Invasive Species Regulations state that alternative measures and the impact on fish and fish habitat or use of fish must be taken into consideration before authorizing the deposit of a deleterious substance. To support the decision making process, the Fisheries and Oceans Canada (DFO) Gulf Region Aquatic Invasive Species National Core Program asked DFO Science to review specific elements of the proponent’s application and advise on the adequacy of the information provided, the interpretation of the literature, and to identify gaps. This Science Response Report results from the Science Response Process of  September 11, 2019 on the review of elements of proponent application to use rotenone for the purpose of eradicating Smallmouth Bass (Micropterus dolomieu) from Miramichi Lake, New Brunswick.