Thirty Years of Pollen Rain Sampling in the Barro Colorado Island 50-ha Plot

Pollen production and dispersal is critical to plant reproduction yet remains poorly understood in tropical forests. To address this knowledge gap, we are conducting a long-term pollen trapping study in the Barro Colorado Island (BCI) 50-ha plot, a study that began in 1991 and continues to this day. Pollen samples from 20 traps on the forest floor are collected annually, processed, and identified to species, providing a 30-year record of pollen rain. The setting is ideal because location of the traps within a large-mapped plot provides information on the sizes and identities of all the trees surrounding the traps, and pollen morphologies of all BCI plant species are well known. Here we describe our methods, review published studies, and present new results on interannual variation in pollen rain in this dataset. We close with discussion of the many possibilities for future research enabled by these data.