Predation on Spider Mite Eggs by the Western Flower Thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), an Opportunist in a Cotton Agroecosystem

Abstract

Larvae and adult females of the western flower thrips, Frankliniella occidentalis (Pergande), showed a functional predatory response to increases in density of spider mite eggs. Female flower thrips showed a faster rate of egg discovery than did larvae, but larval thrips had a higher upper limit for predation than did adult females, which was exhibited by a shorter egg handling time for larvae. Spider mite webbing on the eggs and leaf surface significantly inhibited predation by thrips larvae. Flower thrips are omnivorous opportunists, because they can resort to herbivory when mite eggs are absent or scarce. Thrips are important as herbivores, predators, and prey for other predators. Information on predation by flower thrips will lead to a better understanding of their impact on spider mite populations in the field.