Genetic diversity and dispersal in Northern Rocky Mountain wolves

Apologies for the many recent posts on Northern Rocky Mountain (NRM) wolves, but this fall has seen a number of new studies published that have relevance to management of other species as well. Bridgett vonHoldt and colleagues have a new paper in Molecular Ecology that follows up on their 2008 study of gene flow among wolf populations in the Northern Rocky Mountains. Using new genetic analysis techniques, the authors found that by at least 2004 (the ending date of the genetic data set), genetically effective dispersal had been established between the three wolf populations in the NRM. Measured rates of 5.4 migrants per generation, based on genetic samples from 30% of the NRM wolf population, suggest that total migration rate is at or above the 10 migrants per generation threshold thought to ensure genetic diversity. The authors caution, however, that although this level of dispersal can be expected given recent population numbers, it cannot be assumed if the regional wolf population is reduced to to levels much below current numbers, as has been proposed in state management plans. Using the new techniques developed in this study along with landscape genetics approaches, it may be possible to devise strategies such as wildlife corridors in key dispersal zones that will ensure continued genetic health of NRM wolves in the face of development of rural lands and future changes in wolf population levels. The NRM holds perhaps the best wolf habitat in the contiguous US, so the methods of vonHoldt and colleagues will be even more relevant in restoring wolves to more fragmented landscapes such as the southwest US and the Pacific states.

(full article)