The second edition of this ecological statistics textbook adds two chapters on distinctive statistical methods used for ecological questions. One new chapter covers estimating species richness and other diversity metrics; this chapter focuses on rarefaction curves, although there is a short discussion of Chao’s estimators of assemblage richness. The second new chapter focuses on occupancy modeling with short discussions of mark-recapture models for closed and open populations. Combined with the chapter on ordination that was in the first edition, this volume now provides an introduction to the major areas of ecological statistics.