West Desert Recovery Unit

This is the boundary for the West Desert Recovery Unit for the Utah prairie dog. The West Desert Recovery Unit is primarily in Iron County, but extends into southern Beaver County and northern Washington County. There are 16,841 ac (6,815 ha) of mapped habitat in the West Desert RU (UDWR 2010a). Approximately 39% of the mapped habitat occurs on Federal lands. The West Desert RU contains over 70% of all adult Utah prairie dogs (Table 3). In any given year, 10-20% of the individual adults occur on public lands (Table 6). The West Desert population has fluctuated between less than 1,000 and 4,778 adult Utah prairie dogs (Table 3). Peaks of greater than 4,000 animals occurred in 1989, 2000, and 2005-2010. Between 2000 and 2003, the West Desert RU spring counts showed a decrease from 4,521-2,523 prairie dogs; however, the population rebounded to over 4,000 adult prairie dogs counted each year from 2005 through 2010 (Table 3). Average prairie dog density in the West Desert RU was 0.78 prairie dogs per acre from 2000-2007 (USFWS 2007). See the 2012 Revised Recovery Plan (https://ecos.fws.gov/docs/recovery_plan/1203012_UTPD_RevisedRecoveryPlan_Final.pdf) for more details.本文件为犹他州土拨鼠（Utah prairie dog）西荒漠恢复单元（West Desert Recovery Unit）的边界范围。该恢复单元主体位于艾恩县，同时延伸至比弗县南部与华盛顿县北部区域。西荒漠恢复单元内已完成测绘的栖息地总面积达16,841英亩（6,815公顷），数据引自UDWR 2010年a版报告（UDWR 2010a）。其中约39%的已测绘栖息地位于联邦公有土地范围内。该单元栖息着全美超过70%的成年犹他州土拨鼠，相关统计详见表3。任意单一年份中，仅有10%-20%的成年个体活动于公有土地之上，具体数据详见表6。西荒漠种群的成年犹他州土拨鼠数量一直在不足1000只至4778只的区间内波动，相关数据详见表3。种群数量峰值超过4000只的年份分别为1989年、2000年以及2005年至2010年。2000年至2003年间，西荒漠恢复单元的春季种群普查数据显示种群数量从4521只下降至2523只；但在2005年至2010年期间，种群数量回升至每年成年个体数超过4000只，相关统计详见表3。2000年至2007年间，西荒漠恢复单元内土拨鼠的平均种群密度为0.78只/英亩，数据引自美国鱼类及野生动物管理局（USFWS）2007年报告（USFWS 2007）。如需了解更多细节，请参阅《2012年修订版恢复计划》（https://ecos.fws.gov/docs/recovery_plan/1203012_UTPD_RevisedRecoveryPlan_Final.pdf）。