To inform the conservation of the Regionally Critically Endangered West African lion, we studied lion population size and social structure in Niokolo Koba National Park (NKNP), Senegal. Calling station and camera trap surveys were conducted and opportunistic lion observations were documented from 2015 to 2020. The average lion density was calculated as 0.50 lion/100 km² and the population size was estimated as 28–56 individuals. Average lion group size was 2.1 ± 1.45 lions (range 1–8 lions). There were no significant differences between observations of single individuals (43%), groups of two (22%), three (19%), four (4%) and more than four (5%) individual lions (X² = 30.021, p-value = 0.06452). Sex ratio showed a ratio of male:female of 1:1.1 to 1:2.8. About 13.59% of the lion population was composed of cubs while, respectively, 81.22% and 5.17% were adults and subadults. Based on the analysis of activity patterns, lions in NKNP are mainly nocturno-crepuscular (18:00–01:00) and matutinal (06:00–08:00). Lion population size and density are still low in NKNP compared to earlier estimates from the same area, in the late 1990s. We therefore conclude that the conservation of lions in NKNP must be further improved to safeguard this population in the long term.

中文翻译：

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西非保护区狮子的种群规模和社会结构

为了为西非地区极度濒危狮子的保护提供信息，我们研究了塞内加尔尼奥科洛科巴国家公园 (NKNP) 的狮子种群规模和社会结构。进行了呼叫站和摄像机陷阱调查，并记录了 2015 年至 2020 年期间对狮子机会主义的观察。平均狮子密度计算为 0.50 只狮子/100 km ²，种群规模估计为 28-56 头。狮群的平均规模为 2.1 ± 1.45 头狮子（范围 1-8 头狮子）。对单个个体 (43%)、两个群体 (22%)、三个群体 (19%)、四个群体 (4%) 和四个以上 (5%) 个体狮子的观察结果之间没有显着差异 ( X ²  = 30.021，p值 = 0.06452)。性别比显示，男女之比为1：1.1至1：2.8。狮子种群中约 13.59% 是幼狮，而成年狮子和亚成年狮子分别占 81.22% 和 5.17%。从活动模式分析，NKNP狮子主要以夜间活动（18:00~01:00）和黎明活动（06:00~08:00）为主。与 20 世纪 90 年代末同一地区的早期估计相比，NKNP 的狮子种群规模和密度仍然较低。因此，我们得出的结论是，必须进一步改善 NKNP 中狮子的保护，以长期保护该种群。