FORAGING AND SPATIAL-DISPERSION IN PROTEIN SCAVENGING WORKERS OF VESPULA-GERMANICA AND V-MACULIFRONS (HYMENOPTERA, VESPIDAE)

A series of experiments on the discovery of meat bait by scavenging wo rkers of V. germanica and V. maculifrons showed that workers oriented to meats by visual cues and olfactory cues, Scavenging workers of V. g ermanica and V. maculifrons responded positively to the sight of consp ecifics at meat baits; i. e., meat with (confined) wasps received more visits than meat without wasps. This attraction to conspecific worker s on meat baits provides evidence of local enhancement, in that the pr esence of conspecifics at meat bait directs other wasps to a particula r spatial locality, Local enhancement by yellow jackets foraging for m eat may contribute to the clumped distribution of worker populations n oted in studies of workers captured in meat-baited traps. We hypothesi ze that local enhancement of foraging is a ubiquitous behavior in spec ies of the V. vulgaris species group and may be one attribute explaini ng their ecological success.