Genetic approaches to conservation of rare fishes: examples from North American desert species

Long‐term prospects for conservation of rare fishes depends, in part, on the availability of genetic variation within populations as the raw material to respond to natural selection and allow continued evolutionary change. It is thus important to obtain information on the extent and distribution of genetic variation in rare fishes. There are at least six applications of such genetic data in recovery efforts: description of the quantity and distribution of genetic variation in a species; estimation of historical levels of isolation and gene flow; identification of unique gene pools for special protection; contributions to taxonomic clarifications; information for choosing brood stocks; and monitoring of hatchery populations. It is only through such informed management and with an evolutionary perspective that we can maximize probabilities for conservation in perpetuity of rare fishes.