Effects of founder events on the genetic variation of translocated island populations: implications for conservation management of the northern quoll
Effects of founder events on the genetic variation of translocated island populations: implications for conservation management of the northern quoll
复制标题
DOI：
10.1007/s10592-008-9774-z
复制
发表时间：
2009-12-01
影响因子：
2.2
通讯作者：
Firestone, Karen B.
中科院分区：
文献类型：
--
作者：
Cardoso, Maria J.;Eldridge, Mark D. B.;Firestone, Karen B.
易位是一种常用于最大限度地延长受威胁物种持久性的策略，但有时可能会导致不良的遗传后果。北袋鼬（Dasyurus Hallucatus）是一种肉食性有袋动物，由于最近被外来甘蔗蟾蜍 Chaunus [Bufo] marinus 殖民的地区人口急剧下降，该动物在澳大利亚北领地处于极度濒危状态。 2003年，64只袋鼬被转移到两个近海岛屿，以建立保险种群并降低该物种灭绝的风险。在这项研究中，我们评估了易地种群、两个特有岛屿和三个大陆种群的五个微卫星位点的遗传多样性。在短期（三代）内，与大陆来源种群（A = 5.0-8.4；H（e）= 0.56-0.71）相比，易位种群的遗传多样性略有但不显着减少（A = 4.1-4.2；H（e）= 0.56-0.59）。相比之下，在地方性岛屿种群中观察到高度遗传侵蚀（A = 1.5-2.9；H (e) = 0.11-0.34）。在两个特有岛屿和一个大陆种群中都检测到了遗传瓶颈，表明最近种群规模有所减少。我们的结果与之前的研究一致，之前的研究描述了与大陆人口相比，岛屿上的遗传多样性损失更大。易位群体中与祖先等位基因频率的差异也表明了创始人事件的影响。这项研究虽然是短期的，但强调了持续监测以检测遗传多样性随时间变化的重要性，并为我们了解创始人事件对岛屿人口的影响做出了重大贡献。
Translocation is a strategy commonly used to maximize the persistence of threatened species, but it may sometimes lead to undesirable genetic consequences. The northern quoll (Dasyurus hallucatus) is a carnivorous marsupial that is critically endangered in Australia's Northern Territory due to rapid population declines in areas recently colonized by the exotic cane toad Chaunus [Bufo] marinus. In 2003, 64 quolls were translocated to two offshore islands to establish insurance populations and reduce the species' risk of extinction. In this study, we assessed genetic diversity at five microsatellite loci in the translocated populations, two endemic islands and three mainland populations. In the short-term (three generations), the translocated populations showed a slight but non-significant reduction in genetic diversity (A = 4.1-4.2; H (e) = 0.56-0.59) compared to the mainland source populations (A = 5.0-8.4; H (e) = 0.56-0.71). In comparison, high genetic erosion was observed in the endemic island populations (A = 1.5-2.9; H (e) = 0.11-0.34). Genetic bottlenecks were detected on both endemic islands and in one mainland population, indicating recent reductions in population size. Our results are consistent with previous studies describing greater losses of genetic diversity on islands compared to mainland populations. Divergence from ancestral allele frequencies in the translocated populations also suggests effects due to founder events. This study, although short-term, highlights the importance of continued monitoring for detecting changes in genetic diversity over time and makes a significant contribution to our understanding of the effects of founder events on island populations.