Which pest control method is designed to eliminate fish pests?

The correct choice, piscicides, refers specifically to substances designed to target and eliminate fish pests. These compounds can be used to manage populations of invasive or harmful fish species in aquatic environments, effectively protecting native species and ecosystems. Piscicides can be particularly useful in fisheries management, where controlling certain fish populations is necessary to maintain ecological balance or improve the success of fishery operations.

Understanding the specificity of piscicides helps clarify why the other options are not suitable. Rodenticides are formulated to control rodent populations, not fish. Fungicides target fungal species in plants and do not affect aquatic pests. Herbicides are used to manage unwanted plant growth and would not be effective or appropriate for controlling fish. Therefore, piscicides are the established method for directly addressing challenges posed by fish pests.