string 54 includes a stop 55 to prevent the string 54 from passing completely through opening 53 while the upper end of string 54 includes a hanger 56 which is used to hang apparatus 1 in a location known to be frequented by wasps which are the preferred target insects the dome shape of cover 5 aids in keeping environmental elements such as rain from contacting absorbent pad 16 and its snap fit with ring 13 aids in minimizing evaporation of liquid from pad 16 referring now to fig5 there is illustrated a second reservoir generally designated by the numeral 57 containing a liquid formulated with an active substance toxic to the insect sometimes referred to herein as the u201c liquid active u201d the preferred active or toxicant is an effective concentration of a hemisalt preparation of perfluoroalkane sulfonic acid a sufficient amount of the active is used so that a concentration of 0 001 to 1 5 by weight preferably 0 02 to 0 03 by weight of the active is supplied when the active is admixed with the liquid bait as will hereinafter be described the hemisalt preparation being a partially neutralized preparation of perfluoroalkane sulfonic acid is not very acidic has sufficient water solubility and produces a toxicant attractant formulation that is very attractive to wasps the hemisalt preparation is also stable in carbohydrate solutions the preferred insect attracting ingredient for such insects the hemisalt of perfluoroalkane sulfonic acids can be made by mixing an aqueous solution.