Plant population size has been shown to affect insect visitation and reproductive
success. Small populations are at risk because individuals are more likely to be affected
by stochastic processes and inbreeding depression (Allee effect). Additionally, several
studies have found that plants in small populations also experience lower pollinator
visitation rates, which may further decrease reproduction. In this study, seed set,
pollinator visitation and pollen limitation of Thymus capitatus (L.) was
assessed in 32 patches in eight populations of various sizes on the island of Lesvos,
Greece. All populations except one were significantly pollen-limited. We found that
although free-pollinated flowers produced more seeds in larger populations this was not
due to higher pollinator visitation rates as flowers which received pollen supplements
also produced more seeds in larger populations. We hypothesize that the higher seed set is
due to a generally greater genetic variability or better habitat quality. We show that
honeybee visitation alone significantly decreases pollen limitation
