A trap for assisting in controlling pest populations, in particular rodents, and especially rats and/or mice, including: a lower housing, and a false floor including a trapdoor, and a ramp, wherein the lower housing has a lower end that sits on the ground and an upper end. The false floor is attached to the upper end of the lower housing. The trapdoor is triggered to suddenly collapse when the rodent places a sufficient amount of its body weight onto the trapdoor. The ramp leads up from ground level to the false floor so that when in use, a suitable liquid or gas is contained within the lower housing, and a suitable bait is placed on the false floor to attract a rodent and maneuver it onto the trapdoor. The rodent is able to easily climb up to the false floor by way of the ramp, and when the rodent moves towards the bait, and places sufficient weight upon the trapdoor, the trapdoor suddenly collapses under it, thereby causing it to drop into the lower housing, wherein the rodent drowns in the liquid, or suffocates in the gas.