Infestation of Flour by Tribolium castaneum:1 Rate of Adult Dispersal in Relationship to Sex, Mated Condition, and Other Factors

The average distance at which adult Tribolium castaneum (Herbst) were present below the surface of the flour increased by a mean 21% with each doubling of the time interval. The percentage of total beetles below the surface also increased with time. The number of beetles at a given depth decreased by a nearly constant percentage of the number of beetles at the previous depth with each 2.54 cm increase in depth. These percentages averaged 81, 55, 56, 39, 22, and 6% of the number of beetles at the previous depth in 3, 6, 12, 24, 72, and 144-hr tests, respectively. Rate of adult dispersal in flour generally did not vary significantly with differences in sex, mated condition and density. The rate of dispersal of mated females was similar in the presence and absence of males. Both sexes appeared to have a slight negative geotaxis.