Genetic rescue, the greater prairie chicken and the problem of conservation reliance in the Anthropocene

A central question in conservation is how best to manage biodiversity, despite human domination of global processes (= Anthropocene). Common responses (i.e. translocations, genetic rescue) forestall potential extirpations, yet have an uncertain duration. A textbook example is the greater prairie chicken (GRPC: Tympanuchus cupido pinnatus), where translocations (1992–1998) seemingly rescued genetically depauperate Illinois populations. We re-evaluated this situation after two decades by genotyping 21 microsatellite loci from 1831 shed feathers across six leks in two counties over 4 years (2010–2013). Low migration rates (less than 1%) established each county as demographically independent, but with declining-population estimates (4 year average N = 79). Leks were genetically similar and significantly bottlenecked, with low effective population sizes (average Ne = 13.1; 4 year Ne/N = 0.166). Genetic structure was defined by 12 significantly different family groups, with relatedness r = 0....

保护生物学领域的核心议题之一，是在人类主导全球生态进程（即**人类世（Anthropocene）**）的背景下，如何最优地管理生物多样性。当前常用的干预手段（即种群迁地移植、遗传拯救）虽能延缓潜在的局部种群绝灭，但干预效果的持续时长尚不明确。大草原榛鸡（greater prairie chicken, GRPC：*Tympanuchus cupido pinnatus*）便是经典教科案例：1992至1998年间的迁地移植操作，似乎挽救了遗传多样性匮乏的伊利诺伊州种群。
时隔二十年后，我们重新评估了这一案例：在2010至2013年的四年间，我们采集了两个县域内6处求偶场（lek）的1831枚脱落羽毛，对其中21个微卫星位点（microsatellite loci）进行基因分型。研究显示，种群间迁移率极低（不足1%），证明两个县域的种群在动态上彼此独立，但种群数量估算结果显示其呈下降趋势——四年间平均种群规模（N）为79。各求偶场的遗传背景相似，但均显著经历了遗传瓶颈，有效种群规模（effective population size, Ne）普遍偏低：四年间平均Ne为13.1，Ne与N的平均比值为0.166。种群遗传结构可分为12个存在显著遗传分化的家族类群，其平均亲缘系数（r）为0……