The Barro Colorado Island (BCI) Forest Dynamics Project (FDP) is the longest running large-scale study in the world of a species-rich tropical forest. The project was established to test competing theories at the whole tree community level for the maintenance of tree species diversity in tropical moist forests. The BCI FDP is the flagship project and model for a global network of similar plots established since 1980 throughout the New and Old World tropics. This is a proposal to conduct the sixth complete census of the 50 ha plot on BCI in the year 2005, extending the study to 25 years. The objectives of the sixth census are to update the data on recruitment, growth, and survival of all the non-liana woody plants whose stem diameter is >= 1 cm (about 240,000 plants) since the last census done 5 years ago and to analyze the population trends of each tree species. Most tropical tree species, including those on BCI, are quite rare, and this study is yielding fundamental insights about how tropical tree species manage to persist, despite being rare. The effort would provide training for a number of graduate and undergraduate students in several different countries, will utilize a group of Panamanian botanists, and pay them a "living" wage. The data will be broadly disseminated in both the scientific and lay literature and will be added to a massive and growing database publicly available through the Center for Tropical Forest Studies. These results are important for developing ecologically sound conservation and management strategies for species-rich tropical forests.
