The distinct population segment (DPS) is conservation science jargon for a population that is unique and separate from the species as a whole. The term allows conservationists to propose putting part of a species on the Endangered Species List if the species as a whole is to not in danger of extinction. It is a way to preserve biodiversity within a species. The distinct population segment needs to be discrete and significant in order to merit inclusion on the Endangered Species List as an Endangered or Threatened Species. Individual critters or plants that make up a DPS need to be some how biologically unique from the rest of the species to be considered as such, maybe bigger or smaller, or they may eat different prey, or mate at a different time of year, or have genes that are totally distinct from the rest of the species.
Last Thursday, the Federal Government published what is called their 12-month findings - the decisions on whether to include a whole host of species on the Endangered Species List. When individuals or organizations think a species is in need of protection and inclusion on the list, they may submit a proposal outlining their reasons and the government has 12-months to respond, weighing the data and opinions presented to them. They must decide whether to list the species as in danger of extinct (Endangered), threatened with Endangerment (Threatened), or not in need of protection. Up for consideration was the Sierra Nevada red fox (Vulpes vulpes necator). This closest relative of the Cascade red fox inhabits the mountains of the Sierra Nevada and the Cascades in Oregon and California (Mount Lassen but not Mount Shasta). Based on what is known about this group of mountain foxes, the Federal Government decided that this subspecies occurs as two DPS's (one if California and one in Oregon), that the California DPS warrants listing but the Oregon DPS does not because several recent detections have occurred in the state. Unfortunately the California DPS listing is Warranted But Precluded. More jargon, to mean that the populations in California are in desperate need of protection under the ESA, as they occur as two tiny populations of less than 45 individuals each, but the federal government is not willing to provide support to fund the steps necessary to bring the fox back from the brink.
This is all interesting news for one like myself who has a strong interest in the preservation of the Cascade red fox in Washington. From what the genetic and photographic data that I have collected on the Cascade red fox suggests, these critters occurs as several small populations in southern Washington and are very limited in distribution in the North Cascades. So the decisions made by the U.S. Fish and Wildlife Service vis a vis the Sierra Nevada red fox are telling for decisions made on behalf of the Cascade red fox. If I have learned anything from this ESA listing process, it is that data is power. Without explicit, compelling information, the government and perhaps the citizenry as well, are unlikely to react. It gives me motivation to continue the research we do on these little studied carnivores.