ESTIMATION OF SPECIES RICHNESS: MIXTURE MODELS, THE ROLE OF RARE SPECIES, AND INFERENTIAL CHALLENGES

We examine the role of rare species in the problem of estimating within-habitat species richness based on sampling data. Richness estimation can be modeled realistically for abundance-based and incidence-based data using Poisson or binomial mixtures, respectively. The problem can be reduced to estimation of the odds of the probability of a species remaining undetected in the sample or sample set. Within this rigorous statistical framework, we...