What is the most commonly used fish toxin in aquatic environments?

Rotenone is the most commonly used fish toxin in aquatic environments due to its targeted action against fish and its relative safety to other forms of aquatic life when applied correctly. It works by interfering with the respiratory metabolism of fish, effectively causing suffocation by preventing the fish from absorbing oxygen.

Rotenone is often utilized in fish management practices, such as the removal of undesirable fish species from a body of water or to restore native fish populations. Its application must be carefully managed to minimize impacts on non-target organisms, but it has been a go-to choice for many fisheries and aquatic managers for decades.

In contrast, while aluminum sulfate and copper sulfate can have some effects on fish populations, they are typically not classified as direct fish toxins. Aluminum sulfate is more commonly used as a coagulant in water treatment processes, while copper sulfate is often utilized as an algaecide or fungicide, with a broader range of impacts on aquatic ecosystems.

Endothall is mainly used as an herbicide to control aquatic weeds rather than directly targeting fish. Therefore, when considering effectiveness and common usage specifically as a fish toxin, rotenone stands out as the most prevalent choice in aquatic environments.