What is a Gravid Trap?

• A. A trap that catches larvae.
• B. A trap that targets egg-laying (gravid) female mosquitoes.
• C. A pesticide for adults.
• D. A technique to measure landing rate.

Answer: (B)

Gravid traps are designed to lure and capture gravid female mosquitoes—those that are ready to lay eggs. They use an attractant that mimics a suitable oviposition site, such as a water-based infusion or other odors that gravid females find appealing when they’re ready to lay eggs. Once these females enter the trap, they’re collected for surveillance data, not killed on the spot. This helps programs monitor mosquito populations, species present, and potential disease risk, guiding control decisions.

This differs from traps that are meant to sample larvae, which target the immature aquatic stage rather than adults; from pesticides for adults, which are chemical controls rather than a trapping device; and from methods that measure landing rate, which count how often mosquitoes land on a person or surface rather than capturing them in a trap.