Dj. Rhodes et al., RETENTION OF EXTERNAL AND INTERNAL MARKERS BY SOUTHERN PINE BEETLES (COLEOPTERA, SCOLYTIDAE) DURING GALLERY CONSTRUCTION, Journal of entomological science, 33(2), 1998, pp. 221-232
If retained, markers used in mark-release-recapture studies of bark be
etle dispersal could provide valuable tools in the determination of po
st-dispersal fate. Retention of the internal marker rubidium (Rb) and
of the external marker fluorescent powder during egg gallery construct
ion, oviposition, and feeding were quantified at intervals from 0 to 9
6 h by allowing marked Southern pine beetles, Dendroctonus frontalis Z
immermann, to carry out these activities in untreated host material. S
ignificant differences in Rb concentrations were found between fed and
unfed Rb-marked beetles at all intervals after 12 h. Unfed Rb-marked
beetles were detectable at all intervals, whereas reliable detection o
f fed Rb-marked beetles declined with time. Over 90% of fed southern p
ine beetle marked with fluorescent powder were detectably marked after
96 h, while less than 50% of the Rb-marked beetles were detectable af
ter 72 h. Neither marking technique adversely affected the gallery len
gth or number of eggs produced by marked beetles compared to unmarked
beetles allowed to excavate for 96 h. Practical aspects of both techni
ques are considered.