Recruitment dynamics of a fleshy-fruited plant (Olea europaea): connectingpatterns of seed dispersal to seedling establishment

1 Little is known about the consequences of seed-disperser activity for pla nt demography. We compared the spatial patterns of seed dispersal generated by frugivorous birds with those of seedling survival for the shrub Olea eu ropaea. We examined the relative importance of dispersal in determining pla nt recruitment and tested whether the initial dispersal pattern persisted t hroughout recruitment. 2 We quantified the processes affecting each stage of regeneration (seed wi thin a ripe fruit? dispersed seed, seedling and sapling) in different micro habitats, and evaluated transition probabilities between stages. We could t hen determine the overall probability of a seed in a ripe fruit becoming a sapling, and compare the probability of such an event occurring in differen t microhabitats. 3 Only 9.3% of the emerged seedlings reached the sapling stage, whereas 35. 3% of the seeds were dispersed; 27.0% of dispersed seeds produced seedlings and 62.9% of saplings survived for 2 years. Seedling survival was therefor e the critical link in regeneration. Water stress was responsible for more than 70% of seedling losses, which suggests that abiotic factors (mainly ra infall) may account for most of the fluctuation in recruitment in this spec ies. 4 Neither post-dispersal seed predation nor germination caused changes in t he initial spatial distribution of seeds, but differences in the requiremen ts of seeds and seedlings then caused spatial uncoupling. The most favourab le places for seeds were the worst for seedlings, and consequently frugivor e-generated dispersal patterns differed from the final spatial pattern of r ecruitment. 5 Recruitment under conspecifics was nearly zero and dispersers are therefo re crucial if recruitment is to occur. Their effect on the amount of recrui tment was, however, overwhelmed by processes acting on the seedling stage. 6 For Olea europaea, the pattern generated by short-term recruitment dynami cs persists in the long-term spatial distribution of saplings.