In the present work, a series of tests were performed to examine the effect of previously captured adults in floor traps, on the captures of Trogoderma granarium Everts and T. variabile Ballion, in single species releases. In a first series of tests, a single trap with kairomone oil and dead adults of single or both species was placed in a plastic container, which was used as the release arena. Subsequently, adults of both species were separately released in the arena, and the adult capture was recorded 24 h later. In a second series of trials, two traps were placed in the same arena, containing different numbers of prior seeded adults, and adult capture was similarly recorded. For T. granarium, in all cases, more adults were found inside the trap than under the trap or on the trap walls. In contrast, for T. variabile, most adults were recorded on the trap walls. In general, T. variabile had a stronger response to the traps than T. granarium.This work illustrates that previous captures of either species do not negatively affect captures of new live adults and may tend to enhance captures in some cases. This has important implications for the use of traps for the biosureveillance of these two important dermestid species.