基于种群生存力分析的陕西铜川朱鹮再引入种群的可持续性及保护对策

Sustainability and Conservation Strategies of Reintroduced Crested Ibis Population in Tongchuan,Shaanxi Based on Population Viability Analysis

种群生存力分析(population viability analysis,PVA)虽然已经在濒危物种的保护管理中得到广泛应用,但目前面临的严峻挑战是如何采用PVA分析影响濒危物种种群长期维持的内外因子。经过数十年的保护,朱鹮(Nipponia nippon)野生种群的数量已经从7只增长到约4 400只,若干再引入计划也分别在中国、日本和韩国相继实施。过去的研究表明,种群统计随机性、灾害和种群性比等因素是影响朱鹮野生种群稳定增长的主要因素,然而,对影响朱鹮再引入种群长期稳定维持的因素却知之甚少,这严重阻碍了在释放地开展具有针对性的优先保护计划。本研究在野外收集了2014—2023年铜川朱鹮再引入种群的生活史监测数据,利用基于个体的Vortex模型(Version 10.0),将朱鹮移动的适应模式与环境容纳量、死亡率、扩散、性比和灾害频率相结合,预测该种群的未来生存能力。结果发现,铜川朱鹮种群在未来100年内的存活概率为99.10%,种群规模估计值为508只,种群遗传多样性估计值为0.930 4。敏感性分析表明,种群大小和灭绝概率主要取决于环境容纳量、幼鸟死亡率和扩散存活率。因此,后续的保护措施应优先考虑如何提高与栖息地质量密切相关的环境容纳量、降低死亡率和提高扩散存活率。

Although population viability analysis(PVA) is widely used in the conservation management of endangered species,a daunting challenge of how to incorporate internal and external factors that affect the long-term maintenance of their populations still exists.After decades of conservation efforts,the wild population of the crested ibis(Nipponia nippon) has increased from seven to approximately 4,400 individuals.Several reintroduction programs have also been implemented in China,Japan and Korea,respectively.Previous study suggested that demographic stochasticity,catastrophes,and sex ratio were the main factors affecting the stable growth of the wild population of the crested ibis.However,assessing the longterm impacts from these variables on the reintroduced population is lacking,which adversely affects the implementation of conservation measures in the released areas.From 2014 to 2023,field data on the life history of the reintroduced crested ibis population in Tongchuan City was collected.An individual-based Vortex model(Version 10.0) was then used to predict the future viability of the population by incorporating adaptive patterns of ibis movement in relation to carrying capacity,mortality,dispersal,sex ratio and catastrophe frequency.Results showed that the survival probability of the reintroduced crested ibis population in Tongchuan City was 99.10% over the next 100 years.The population size was estimated to be 508,and the population genetic diversity was estimated to be 0.9304.Sensitivity analysis showed that population size and extinction probability were primarily dependent on carrying capacity,fledgling mortality and survival rate of dispersers.Therefore,subsequent conservation priorities should be the carrying capacity enhancement,increasing survival rate of dispersers and reducing mortality.