Predation on Potato Moth, Phthorimaea Operculella (Lepidoptera: Gelechiidae), by the Western Silvereye, Zosterops Gouldi (Aves: Zosteropidae).

Abstract

The omnivorous bird, the western silvereye, eats the larvae of potato moth, preferring the larger third and final fourth instars. An examination of the gizzard contents shows that silvereyes eat proportionally fewer third-instar larvae when the density of the moth population is low, despite the equal abundance of third and fourth-instar larvae. With increasing moth density, the third- instar larvae become increasingly attractive. It is inferred that the level of crop infestation determines whether the smaller third-instar larvae are as profitable as energy sources as the fourth-instar larvae.