Washington ground squirrels (Spermophilus washingtoni) are small, gray-brown sciurids with light spots on the back. Originally abundant in the bunchgrass and sagebrush habitats throughout the Columbia Plateau east and south of the Columbia River in Washington and Oregon (Bailey 1936; Howell 1938), their range has greatly reduced in recent years, due mostly to loss and fragmentation of habitat (Betts 1990). The species is currently listed by the Oregon Department of Fish and Wildlife as criticalJ meaning that its listing as threatened or endangered is either pending or may be necessary if appropriate conservation measures are not undertaken (Marshall and others 1992). In Washington, S. washingtoni is listed by the Washington Department of Fish and Wildlife as a protected species, meaning that it cannot be hunted, killed, injured, or harassed (Washington Administrative Code 232-12011). In a survey conducted from 1987 to 1989t I found that S. washingtonz had disappeared from 48 (73.8%) of 65 and from 20 (76.9%) of 26 previously reported sites in Washington arld Oregon, respectively. I found evidence of squirrels at 87 new and previously reported sites (Betts 1990). Since that survey I have noted the absence of squirrels during irregular checks of a few of the Oregon sites. In April 1998, I received reports that squirrels were absent from 7 additional sites and were present in low numbers at 5 other sites in Oregon (Eric Yensen, Albertson College of Idaho, Caldwell, ID, pers. comm.; Paul W. Sherman, Cornell University, Ithaca, NY, pers. comm.). Because of these observations and the official concern for this species by wildlife managers in both states, I again surveyed most of the 87 confirmed and probable sites that I identified previously. I visited sites on 1J 2, 3, and 12 May 1998. At each site I seardhed for active burrows and listened and watched for squirrels. I also interviewed residents, other researchers, and wildlife managers. The results for Oregon are bleak. There was clear evidence of squirrels at only 9 (25%) of 36 sites. At 4 of these sites, I found several active burrows. I did not personally 07isit the other 5 sites, which are on the southern half of the Boardman Naval Weapons Systems Training Facility (hereafter, bombing range), but squirrel presence there has been confirmed by other researchers (Quade 1994; Eric Greene, Oregon State Universityf Corvallis, OR, pers. comm.; E. Yensen, pers. comm.; P. Sherman, pers. comm.). Also, all 7 of the sites added to the Oregon Natural Heritage Program data base since 1990 are on the bombing range. Squirrels may also have been present at 2 other sites where I found only 1 or 2 burrows that I had difficulty classifying as active. At the other 25 sites I found no burrows that appeared active and neither saw nor heard squirrels. Residents near many of these sites typically stated that they had not seen any squirrels for 3 to 4 years. Disappearance of S. washingtoni from these 25 sites represents a 69% decrease in active sites from those I found in 1987 to 1989. The situation is even worse when considering the locations of the remaining sites. All but 1 of the confirmed sites are on the bombing range or just south of it. The other site/ south of Arlington, is the northwesternmost previously surveyed site. One of the 2 possible sites is near Ione southwest of the bombing range and the other is just south of Nolin on the eastern edge of the Oregon range of the species. Thus/ my survey suggests that squirrels exist outside the bombing range only in a limited number of isolated sites. The results for Washington are somewhat more promising. I visited 47 of 51 previously identified sites (Betts 1990) and found erridence of squirrels at 37 (73%). But again, the distribution of the sites where I no longer found squirrels suggests the potential for further range reduction. Squirrels were gone from 5,