Data from: Assessing the sustainability of African lion trophy hunting, with recommendations for policy

While trophy hunting provides revenue for conservation, it must be carefully managed to avoid negative population impacts, particularly for long-lived species with low natural mortality rates. Trophy hunting has had negative effects on lion populations throughout Africa, and the species serves as an important case study to consider the balance of costs and benefits, and to consider the effectiveness of alternative strategies to conserve exploited species. Age-restricted harvesting is widely recommended to mitigate negative effects of lion hunting, but this recommendation was based on a population model parameterized with data from a well-protected and growing lion population. Here, we used demographic data from lions subject to more typical conditions, including source-sink dynamics between a protected National Park and adjacent hunting areas in Zambia’s Luangwa Valley, to develop a stochastic population projection model and evaluate alternative harvest scenarios. Hunting resulted in population declines over a 25-year period for all continuous harvest strategies, with large declines for quotas greater than 1 lion/concession (~0.5 lion/1000 km2) and hunting of males younger than 7 years. A strategy that combined periods of recovery, an age limit of ≥ 7 years and a maximum quota of ~0.5 lions shot per 1000 km2 yielded a risk of extirpation < 10%. Our analysis incorporated the effects of human encroachment, poaching and prey depletion on survival, but assumed that these problems will not increase, which is unlikely. These results suggest conservative management of lion trophy hunting with a combination of regulations. To implement sustainable trophy hunting while maintaining revenue for conservation of hunting areas, our results suggest that hunting fees must increase as a consequence of diminished supply. These findings are broadly applicable to hunted lion populations throughout Africa, and to inform global efforts to conserve exploited carnivore populations.

尽管战利品狩猎（Trophy Hunting）能为物种保护带来收入，但必须对其进行严格管控，以避免对种群产生负面影响，这一点对于自然死亡率较低的长寿物种尤为关键。战利品狩猎已对非洲全境的狮子种群造成负面影响，而狮子也成为了权衡保护成本与收益、评估受猎捕物种保护替代策略有效性的重要研究案例。目前学界广泛建议通过限龄狩猎（Age-restricted Harvesting）来缓解狮子狩猎带来的负面影响，但该建议的提出基于一个受保护程度高且种群处于增长状态的狮子种群数据所构建的种群模型。本研究采用来自更具典型性环境下的狮子种群人口统计数据——包括赞比亚卢安瓜谷某受保护国家公园与周边狩猎区域之间的源-汇动态（Source-sink Dynamics）——构建了随机种群预测模型，并对多种替代狩猎方案进行了评估。所有持续性狩猎方案在25年周期内均导致种群数量下降，当狩猎配额超过1头狮子/特许狩猎区（约0.5头狮子/1000平方千米），或狩猎对象为7岁以下雄性狮子时，种群下降幅度尤为显著。若采用包含种群恢复期、7岁及以上年龄限制，且最大配额为每1000平方千米狩猎0.5头狮子的方案，则种群局部灭绝（Extirpation）风险低于10%。本研究的分析纳入了人类侵占、偷猎以及猎物枯竭对狮子存活率的影响，但研究假设上述问题不会加剧——而这一假设在现实中并不成立。上述结果表明，需通过多项监管措施对狮子战利品狩猎实施保守化管理。若要在维持狩猎区域保护收入的同时实现战利品狩猎的可持续性，研究结果显示，由于狩猎配额供给减少，狩猎费用必须相应上调。本研究结果可广泛应用于非洲全境受狩猎影响的狮子种群，也可为全球受开发食肉动物的保护工作提供参考。