Resting Places, Dispersal and Survival of Co60-Tagged Adult Rhodnius Prolixus1

Abstract

A test with wild R. prolixus was programmed to observe dispersal, resting place preferences and survival of CO60-tagged adult specimens released on palm trees and houses. Tagging consisted of internally placed, gold covered CO60 wires of approximately 75 microcuries. Results indicate that dispersal by the insects' own means of locomotion is motivated mainly by starvation and that emigration from palm trees to houses was greater than between palms and between houses; no specimen went from house to palm. Dispersal, during 40 days, did not exceed 15 m outdoors or 4 m indoors. Resting place preferences were leaf bases on palms, thatched roofs, household articles, and wall crevices indoors. R. prolixus tends to concentrate in the immediate vicinity of food sources. Average survival was about 20 days. The main cause of death is predation by fowl, and to a lesser extent by other vertebrates and arthropods. The observed rate of migration from palm to house suggests that direct house infestation by palm-inhabiting R. prolixus is probable only when highly infested habitats are in the vicinity.