What is Biological Control?

• A. Use of natural predators or pathogens (e.g., mosquitofish, Bti) to control mosquitoes.
• B. A trap aimed at gravid mosquitoes.
• C. A surveillance method counting landings.
• D. A pesticide that kills adults.

Answer: (A)

Biological control means using living organisms or their products to reduce mosquito populations. In practice, that includes introducing or encouraging natural enemies of mosquitoes or substances produced by microbes that specifically target mosquito larvae. For example, mosquitofish can be used in standing water to feed on larvae, directly lowering the number that reach adulthood. Another common approach is Bacillus thuringiensis israelensis (Bti), a bacterium that produces toxins when ingested by larvae, killing them while being relatively safe for other wildlife and humans when used as directed. These strategies rely on natural biological relationships to suppress pests rather than broad chemical sprays. In contrast, a trap aimed at gravid mosquitoes is a monitoring or capture tool, a surveillance method counts landings is just tracking activity, and a pesticide that kills adults is chemical control, not biological.