When do gravid traps catch the greatest number of mosquitoes

Gravid traps are most effective at catching mosquitoes during the peak activity times for the target species—typically dawn, dusk, and nighttime for Culex mosquitoes.

• Mosquito activity window: Most disease-carrying gravid female mosquitoes (such as Culex spp., often targeted by gravid traps) are most active at dawn, dusk, and nighttime.
• Trap deployment best practice: Set gravid traps in late afternoon or early evening (typically 2–4 p.m.), leave them out overnight, and collect contents in the early morning (8–9 a.m.). This timing matches the high activity and oviposition period of the target species.

Summary:
Gravid traps will catch the most mosquitoes if deployed during the peak activity period of the species. For most species (especially Culex), this means overnight trapping—covering dusk, night, and dawn—is optimal.

If you target a mosquito species with a different peak activity time, adjust the trap schedule accordingly for maximum catch rates.