As briefly described in Appendix A, there are three qualifiers that may be appended to conservation status ranks: ? = imprecision, Q = questionable taxonomy, and C = captive or cultivated (for species only). These qualifiers are used either to indicate the degree of uncertainty associated with an assigned status rank, or to provide additional information about the ecosystem or taxon that has been assessed.
? – Inexact Numeric Rank. The addition of a ? qualifier to a 1-5 conservation status rank denotes that the assigned rank is imprecise. This qualifier is used only with the numeric status ranks, not with X, H, or U ranks, or range ranks. As described in previous sections, uncertainty about the exact status of a species or ecosystem is usually denoted by a range rank, with the range indicating the degree of uncertainty; however a #? may also be used. Figure 3 below illustrates the uncertainty associated with different status ranks.
Figure 3. Comparison of uncertainty associated with examples of an exact status rank, rank with ? qualifier, and range ranks.
Q – Questionable taxonomy, which may reduce conservation priority. Use of the Q qualifier denotes that the distinctiveness of the assessed entity as a taxon or ecosystem type at the current level is questionable. More importantly, use of the Q further indicates that resolution of this uncertainty may result in a change, either from a species to a subspecies or hybrid, or inclusion of the assessed taxon or ecosystem type in another taxon or type, such that the resulting taxon/type will have a lower-priority (numerically higher) conservation status rank than that originally assigned.
An example of an invalid use of the Q qualifier would be a G5Q, which is not appropriate since resolution of the uncertainty associated with the assessed taxon or ecosystem type could not result in a taxon or type with a conservation status that is lower priority (higher numerically) – the assigned status (5) is already the lowest priority. Similarly, a taxon or type that may be split into several new species or types would not qualify for a Q qualifier as the conservation statuses of the resulting entities would either stay the same or have higher priority (become numerically lower); for example, a G4 taxon or type is split into three G2 and G3 ranked (higher-priority) taxa/types. Note that the Q modifier is only used with global level conservation status ranks, and not at a national or subnational level. Note also that other data fields are available at a global level to specify taxonomic uncertainties, regardless of resolution of the taxonomic uncertainty on the conservation status.
C – Captive or Cultivated Only. The C qualifier is used to indicate that a taxon, at present, is extinct in the wild across its entire native range, but is extant in cultivation, in captivity, as a naturalized population (or populations) outside its historical native range, or as a reintroduced population not yet established. Note that the C modifier is only used for species status ranks at the global level, and not at a national or subnational level.
NatureServe Conservation Status Assessments: Factors for Evaluating Species and Ecosystem Risk