Abstract
Behaviour of adult pine bark weevils (Shirahoshizo spp.; including three species) in selecting habitat for oviposition was determined by their responses to pine bait logs. Movements of adults were monitored using capture-recapture data. Logs having larger surface area and more thick bark were colonized by more adults. By partial correlation coefficients, the effect of bark thickness was found stronger than that of surface area. The main part of tramping (i.e. intra-plot movements) consisted of mutual interchanges among logs having many immigrants, but there was no tendency for adults to congregate upon any particular log. The constancy of the tramp ratio for a wide range of immigration density indicated that about one half of the immigrants on each log emigrated from the plot without any intra-plot movements. The duration time of staying on a log did not change significantly with log size. Emergence of progeny was restricted to logs having bark more than about 1.5mm thick.
