不同模拟情景下长江江豚种群生存力分析

Analysis of population viability analysis of Yangtze finless porpoise in different simulated scenarios

中文关键词: 长江江豚  种群生存力  旋涡模型  死亡率  生殖率

英文关键词: Yangtze finless porpoise  PVA  Vortex model  Mortality  Breeding

中文摘要:

      为了探讨长江江豚(Neophocaena asiaeorientalis asiaeorientalis)种群的生存动态和管护对策，本研究利用漩涡模型(Vortex 10.3.7.0)对长江江豚种群生存力进行了回顾和现状分析。结果发现，以1999年作为回顾分析起点，长江江豚的灭绝概率最可能为0.0754，且不高于0.5629。平均灭绝时间最可能为93.5年，且不少于87.9年。以2017年作为现状分析起点，长江江豚种群灭绝概率为0.3551~0.6985，平均灭绝时间为83.5~88.0年。在特定情景下，设定新生幼豚雄性所占比例分别为0.55、0.50和0.45，经模拟计算得出，雄性化让灭绝概率由0.6985增加到0.9157，雌性化使其下降到0.3664。同时，数据比较发现，新生幼豚雄性所占比例下降10%，成年雌豚生殖率提高10%，二者最终效果相当。上述研究结果表明，长江江豚种群生存风险较大，需重点保护，修复其生境，尤其是母子豚相关生境有利于长江江豚的保护。

英文摘要:

      To study the population dynamics and conservation strategies of the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis), Vortex (v.10.3.7.0) was used to analyze the population viability. Taking 1999 as the starting point, a retrospective analysis revealed that the extinction probability of finless porpoise was most likely to be 0.0754 and was not higher than 0.5629. The mean extinction time was most likely to be 93.5 years and not less than 87.9 years. Taking 2017 as the starting point, through the analysis of the current situation, it was found that the extinction probability of the Yangtze finless porpoise population was 0.3551~0.6985, and the average extinction time was 83.5~88.0 years. In certain situations, the proportion of newborn male Yangtze finless porpoise was 0.55, 0.50, and 0.45, respectively. The results showed that masculinization increased the probability of extinction from 0.6985 to 0.9157, and feminization brought it down to 0.3664. At the same time, comparison of the data found that a 10% decrease in the proportion of newborn males and a 10% increase in the breeding rate of adult females had the same effect. The above results suggested that the extinction risk of the finless porpoise population in the Yangtze River was relatively high. Focusing on the protection and restoration of high-quality habitats, especially those related to parents–children, is important for the protection of the Yangtze finless porpoise.