Residue Levels of the Lampricides TFM and Niclosamide in Moribund Sea Lamprey Larvae Following Exposures to TFM and a TFM/1% Niclosamide Combination

Science Center Objects

Concerns regarding the exposure of wildlife to TFM and niclosamide that would result from the consumption of sea lamprey (Petromyzon marinus) larvae exposed to these chemicals has prompted a need to investigate uptake of these chemicals in larval lampreys. A study to address concerns regarding the exposure of the endangered common term during the treatment of the St. Marys River was completed in 1999. Ammocoetes exposed to a lethal concentration of niclosamide contained an average of approximately 3.53 g of niclosamide per gram of tissue. Complimentary data on TFM has not been generated. We propose to complete the data base by conducting a study to determine residues of TFM and niclosamide in ammocoetes following exposure to TFM and a TFM/1% niclosamide mixture. 

The results of this research may lead to a more conscientious use of the lampricides to control lamprey populations in the Great Lakes by implementing procedures to protect lampricide sensitive non target species after a treatment. Judicious use of lampricides to control lamprey populations in the Great Lakes is critical to sustaining the Great Lakes fishery industry.


Provide data that will facilitate assessments of the potential effects of TFM and niclosamide resulting from consumption of dead or moribund sea lamprey larvae by wildlife.


Aaron Cupp adding formalin to test aquaria
(Public domain.)