Field Performance of a New Formulation of the Screwworm Adult Suppression System

A new pelletized formulation of the Screwworm Adult Suppression System (SWASS) was evaluated in Jeff Davis Co., TX, for effectiveness under field conditions. In 2 separate field evaluations, SWASS pellets prepared from 30.5% sugar, 30.5% dried blood, 7.5% corn cob grits, 2% dichlorvos, and 29.5% of a hardened wax preparation of swormlure-2 (82% swormlure-2, 18% wax) were applied aerially twice weekly at the rate of 1 kg/5.7 km2. In the 1st test, the SWASS pellets reduced populations of native screwwonn, Cochliomyia hominivorax (Coquerel) ca. 84% and populations of secondary screwworm C. macellaria (F.), ca. 90%. In a 2nd test, the SWASS pellets reduced the native screwworm population ca. 72–95%. The new formulation of SWASS is compact and appears amenable to mass production.