A method of ranking species and sites for conservation using presence-absence data and its application to native freshwater fish in new zealand

Abstract

Rareness or percent occurrence for species is derived from presence/absence matrices (sites X species) and used to calculate a set of indices for ranking sites and species. The indices are designed to weight for sites with greater species richness and presence of rare species. New Zealand native freshwater fish distributions are used as an example. Map quadrants and catchment areas with high index values are identified. The ranks are compared with selections made by experts and found to agree closely. The advantages and disadvantages of the method are discussed along with its place in reserve design. © The Royal Society of New Zealand 1993.