Nonrandom Provisioning by the Digger Wasp, Palmodes laeviventris (Hymenoptera: Sphecidae)

Predation strategies of Palmodes laeviventris (Cresson), a predator of Mormon crickets, are described. Prey taken are compared with prey available. Although mean prey sizes are no larger than the population means, a positive correlation between wasp size and prey size indicates that females do take large prey but are limited by their own body size. Size selection by wasps may explain the strong bias toward female prey. An alternative hypothesis is that the sex bias is a result of female Mormon crickets being more vulnerable to predation because they are more exposed than males due to their reproductive behavior.