Effects of Prey Availability on Longevity, Prey Consumption, and Egg Production of the Insect Predators Orius sauteri and O. tantillus (Hemiptera: Anthocoridae)

Abstract

We determined how prey [Thrips palmi (Thysanoptera: Thripidae)] availability differentially affects longevity, prey consumption rates, and egg production rates in 2 predacious insects, Orius sauteri (Poppius) and O. tantillus (Motschulsky), which are temperate and subtropical species, respectively. Orius sauteri had a stronger increase in prey consumption and egg production rates with prey availability than did O. tantillus. Orius sauteri females exposed to high prey availability lived less long than O. tantillus females, whereas there was little difference in female longevities when prey availability was low. The different effects of prey availability on egg production of O. sauteri and O. tantillus influenced reproductive costs in these 2 species. Differences in resource allocation to reproduction and survival between the 2 species is probably a result of their different climatic distributions. The importance of reproductive cost of insect predators in response to prey availability in interaction between predator and prey is discussed.