The indirect impacts of Shorea siamensis-logging on the reproductive ecology of Dipterocarpus obtusifolius, a selfincompatible
butterfly-, moth-, and bird-pollinated tree, were studied in tropical dry forest in Thailand. Pollinator
activity at D. obtusifoiius trees and subsequent seed production were recorded in three forest areas subject to differing
intensities of S. siamensis extraction. The pollinator and plant understory communities in these areas were also noted.
Forest areas subject to high S. siamensis extraction intensities had very high understory flowering plant cover, dominated
by the exotic invader Chromokzena odorata. Activity of butterfly pollinators at D. obtusifoiius trees decreased in these
disturbed areas, although their abundance remained comparable to other forest areas subject to only moderate or no
extraction. For sphingid moth pollinators, there was no difference across differentially disturbed forest areas in either
abundance or in the proportion bearing pollen. Pollinator activity by birds increased at highly disturbed locations but
was not sufficient to offset a decline in overall pollinator activity at D. obtusifolius canopies in areas of heavy S.
siamensis extraction. Thus, extraction of S. siamensis indirectly affected the pollination of D. obtusifoliw, primarily by
causing changes in the foraging behavior of butterfly pollinators rather than their abundance. A shift in the relative
abundance of floral nectar resources from the canopy to the understory, a consequence of S. siamensis extraction and
invasion by C. odorata, led to a parallel shift in foraging location of the principal diurnal pollinators, the butterflies,
toward the understory. Despite reduced pollination at disturbed sites, behavioral changes did not translate into a D.
obtusifoiius seed set effect, possibly because pollination by birds (or moths) at the disturbed site compensated for
reduced butterfly pollination.