What are chemical substances poisonous to fish called?

Piscicides are chemicals used to kill fish. They can be used in a variety of aquatic environments including lakes and rivers. There are four chemical piscicides registered for use in the United States: antimycin A, rotenone, niclosamide and TFM.

Originally, piscicides were mainly used to control out-of-balance or undesirable fish populations so that sport fish could be stocked for recreational purposes. Today, antimycin A and rotenone are used to control fish populations for a variety of purposes.

Although physical removal methods (e.g., nets, traps, seines, electro-fishing, dewatering, and combinations of physical control techniques) are available for reducing or controlling fish communities, they are generally incapable of eradicating situations with out-of-control or undesirable fish populations.

Please note that all piscicides and users must comply with U.S. Environmental Protection Agency (USEPA) laws and regulations. Piscicides are restricted use items and as such all users are required to be certified. Users should not handle any piscicides if they are not authorized to do so.