Designing and Testing Sampling Protocols to Estimate Biodiversity in Tropical Ecosystems

TLDR: In this article, the authors proposed a set of methods that seek the optimal compromise between systematics and community ecology to estimate the species richness of a defined area (conservation unit, national park, field station, or community).

Abstract: Sampling methods to estimate total species richness of a defined area (conservation unit, national park, field station, "community") will play an important role in research on the global loss of biodiversity. Such methods should be fast, because time is of the essence. They should be reliable because diverse workers will need to apply them in diverse areas to generate comparable data. They should also be simple and cheap, because the problem of extinction is most severe in developing tropical countries where the scientific and museum infrastructure is often still rudimentary. In the past, two scientific fields have been mainly responsible for providing such data: systematics and community ecology. Simplistically summarized, samples collected by systematists better represent the species richness in an area but are intractable statistically, whereas the analysis of samples collected to answer ecological questions is usually straightforward but often poorly represents the total fauna. The two approaches are complementary and we propose a set of methods that seeks the optimal compromise. We applied these methods to sample and estimate species richness of Araneae in Bolivia, but we present criteria so that the methods can be modified for other broadly similar groups. We describe the methods used, present preliminary analyses of the effect of four variables (site, collecting method, collector, and time of day) on total number of adult individuals taken, and discuss analytical approaches that employ such data to estimate total species richness. We also present data from Peruvian canopy fogging samples to show that estimates of species richness of diverse tropical arthropod taxocenes are obtainable in principle.