Scott Willis of the Calascieu Parish Mosquito Control branch in Lake Charles, Louisiana wanted to see if the the BG-Counter could also be used to count mosquitoes trying to find an oviposition site. There is a fan-driven trap that collects just those: The CDC gravid trap, first published by Paul Reiter in 1983 (Mosquito News 43: 496-498). The trap is essentially a fan and a catch bag over a tray of water. Gravid female mosquitoes inspecting the water surface to lay eggs are vacuumed into the catch bag.
For more details, look at the talk Scott gave at the 2017 Annual Meeting of the Louisiana Mosquito Control Association in Covington, LA: “Use of the Biogents BG-Counter with gravid mosquitoes and the efficacy of aerial applications for nuisance mosquitoes“, given on December 6th, 2017.