Selecting indicator taxa for the quantitative assessment of biodiversity

Seven criteria are presented that can be used to objectively test the claim that a given taxon is an ideal indicator: 1) well known and stable taxonmy; 2) well known natural history; 3) readily surveyed and manipulated; 4) higher taxa broadly distributed geographically and over a breadth of habitat types; 5) lower taxa specialized and sensitive to habitat changes; 6) patterns of biodiversity reflected in other related and unrelated taxa; and 7) potential economic importance. These criteria have different priorities depending on which of two general categories of biodiversity the indicator taxon is to be used. Monitoring places an emphasis on sensitivity to habitat change, and inventory places an emphasis on systematics. An index is suggested by which the results of selecting an indicator taxon can be more accurately communicated. -from Author