Two reported oviposition attractants for Aedes triseriatus, fish oil emulsion and water of high optical density, were evaluated in ovitraps in the field. Solutions of fish oil emulsion at 1% repelled ovipositing mosquitoes, whereas water containing vegetable dye increased oviposition up to 4-fold over control traps. Laboratory bioassays with fish oil emulsion at both 1 and 5% confirmed the field results.