Genetic Analysis of Columbian Sharp-Tailed Grouse: A Preliminary Study - Final Report

The historical range of the Columbian Sharp-tailed Grouse (Tympanuchus phasianellus columbianus) extended from the steppe- and shrub-dominated habitats in the inter-mountain regions from British Columbia south to California, Nevada, and Utah, and east to western Montana, Wyoming and Colorado. The subspecies has been extirpated from most of its range and exists now as remnant and isolated populations. The core of Columbian Sharp-tailed Grouse distribution occurs as scattered populations in southeast Idaho and northern Utah where 50-70% of the subspecies’ total abundance currently resides (USFWS, 1999). The decline of Sharptailed Grouse in Washington has been precipitous and extreme, and it now exist in only six to eight small and fragmented populations in Douglas, Lincoln, and Okanogan Counties (Hays et al., 1998).

As part of Washington Department of Fish and Wildlife’s continuing assessment of the status of and recovery efforts for Sharp-tailed Grouse in the state, we have initiated a project to evaluate this subspecies’ geographic structure and population genetics in Washington and neighboring states. One of the primary objectives of this study is to determine the genetic relationships of the existing Columbian Sharp-tailed Grouse populations. The purpose of this activity is to determine if cross-transplanting birds from neighboring populations within Washington or moving birds from viable population in Idaho and Utah into Washington is feasible and appropriate. In addition, a genetic analysis of Columbian Sharp-tailed Grouse populations would also permit us to evaluate the degree to which the small and isolated populations in Washington have experienced a loss of genetic diversity either through genetic drift or inbreeding. A loss in genetic diversity may be associated with or foretell a decrease in overall population fitness, similar to that which occurred in the congeneric Greater Prairie Chicken (Tympanuchus cupido; Bouzat et al., 1998a,b).

The purpose of this document is to report the results of a preliminary analysis of the population genetics of Columbian Sharp-tailed Grouse, primarily from two general localities in Washington and Idaho. The activities associated with the report were funded by US Department of Interior, Bureau of Land Management (BLM; Contract # HWP000025). The intent of this initial project was to develop laboratory protocols for the amplification and scoring of microsatellite loci, and to provide a preliminary assessment of genetic diversity and geographic structure of Columbian Sharp-tailed Grouse.