West Mojave Plan FEIR/S - Desert Managers Group

of the other wilderness areas. Although sample sizes were relatively small, data that werecollected are given in Table 3-30, including the number of tortoises, number of higher densitytortoise areas, tortoise sign (TCS), and carcasses observed. The area of survey is importantrelative to each of the observations, so the numbers of tortoises, carcasses, etc. are shown inparenthesis as the percent of transects surveyed within the area of comparison.Table 3-30Sign Count Tortoises, Carcasses, and Total Corrected Sign (TCS)Observed within Each of the Eight Wilderness Areastortoise observationsWilderness Area(No. Transects)No.TortoisesNo. ofCarcassesNo./%w/out SignNo./%w/ SignRange(Sum)Averagew/ Sign 21 Mi 2 AboveAverageCleghorn Lakes (12) 3 (25%) 2 (17%) 4 (33%) 8/67% 0-20 (96) 12 8Black Mountain (21) 1 (5%) 2 (9%) 3 (14%) 18/86% 0-34 (158) 9 6Rodman Mountains (29) 4 (14%) 3 (10%) 8 (27%) 21/73% 0-14 (105) 5 5Newberry Mountains (15) 2 (13%) 3 (20%) 3 (20%) 12/80% 0-4 (23) 2 0Sheephole Valley (5) 0 (0%) 0 (0%) 2 (40%) 3/60% 0-14 (17) 6 0Golden Valley (14) 0 (0%) 1 (7%) 9 (64%) 5/36% 0-1 (5) 1 0Grass Valley (35) 0 (0%) 8 (23%) 23 (66%) 12/34% 0-3 (19) 2 0El Paso Mountains (10) 0 (0%) 0 (0%) 7/70% 3/30% 0-3 (6) 2 0Totals 10 19 59 82 0-34 (53.6) 4.9 19The numbers would be interpreted using, for example, the Cleghorn Lakes WildernessArea: 3 tortoises were found on the 12 transects (25%) surveyed; 2 carcasses (17%) were found;no sign was found on 4 (33%) transects; tortoise sign was found on 8 (67%) transects; a total of96 pieces of sign were found, ranging from 0 to 20/transect; there was an average of 12 signfound on the 8 transects with sign; and there were 8 mi 2 of higher sign count areas.These comparisons suggest that Cleghorn Lakes, Black Mountain, Rodman Mountains,and Newberry Mountains provide the most tortoise conservation value in terms of currenttortoise occurrence. There were too few transects surveyed in the Sheephole Valley to determinewhere it would fit into this order. Golden Valley, Grass Valley, and El Paso may providerelatively less conservation value, although this may be more reflective of recent tortoise die-offsthan lower conservation value. Note for example, that more carcasses were found in GrassValley relative to the survey effort than any other area; so this area may have outstanding tortoisevalue, but older die-offs have affected the number of tortoises currently present.The spatial distribution of the eight wilderness areas is an important factor regarding therelative value of these areas for tortoise conservation. Cleghorn Lakes and Black Mountainappear to be the two most valuable areas in terms of tortoise occurrence. The Cleghorn Lakesarea is bisected by the 29 Palms Marine Corps Base, and the northern portions of this wildernessarea on the base also support relatively higher tortoise concentrations (data were unavailablefrom 29 Palms for analysis, but show a concentration area immediately north of the oneoccurring on BLM-managed lands). It is very isolated from human uses, and not near any die-21The “Average with Sign” column reports the average number of tortoise sign on the transects where sign wasfound, so that transects with zero sign counts have been excluded.Chapter 3 3-140