(60) Importance of Seedling Establishment to Population Persistence in a Clonal Tropical Tree Species

     Population maintenance in tropical rainforest tree species is typically dependent on the regular production of sexually produced offspring over time. Clonal tree species, however, do not necessarily depend on the... [ view full abstract ]

     Population maintenance in tropical rainforest tree species is typically dependent on the regular production of sexually produced offspring over time. Clonal tree species, however, do not necessarily depend on the regular establishment of seedlings for continued population maintenance. In the Belizean rainforest, Coccoloba belizensis is an unusual tree species in that it is characterized by populations consisting of long-lived clones that produce a thick layer of leaf litter. We hypothesized that seedlings in Coccoloba populations would be rare and would not present where there was a high percentage of leaf litter under adult trees.  Our study took place in the Chiquibul rainforest at the Las Cuevas Research Station in western Belize and consisted of two parts 1) population mapping in two 2500 m² plots and 2) a seedling status assessment. The majority of all Coccoloba seedlings examined in the study were located more than 20 meters away from the nearest parent tree and were present outside the influence of adult leaf litter. Within the two mapped populations, we found only 9 seedlings. The size class distribution of individuals in the mapped populations suggested that recruitment of new adults from seedlings was extremely rare.  However, in a population where clonal individuals can live hundreds of years through continued stem replacement, rare recruitment events involving sexually produced offspring may be sufficient for population maintenance over time. Our study represents one of the few assessments of the importance of clonality in the population dynamics of tropical tree species.