Assessing puma habitat suitability in Uruguay’s Grasslands: exploring source-sink dynamics and conservation implications

Pumas (<i>Puma concolor</i>) have a broad geographic range across the Americas and are globally listed as Least Concern. However, in Uruguay’s Pampas Grasslands, they are considered Data Deficient and regionally endangered in Argentina and Brazil. Understanding the distribution and population status of pumas is crucial for their conservation. This study examines puma occurrence in Uruguay’s Grasslands within a regional context, assessing habitat suitability and recent land use changes. Using a Species Distribution Model (SDM) in MaxEnt with 224 occurrence records (1999–2011) and bioclimatic and topographic predictors, we found intermediate habitat suitability in the Pampas Grasslands, indicating a naturally sparse puma population. The highest suitability was along riverbanks and riparian areas. Recent land use changes have transformed suitable habitats into areas less likely to support pumas, affecting a significant portion of Uruguay’s land. Our results suggest source-sink dynamics, where Uruguayan puma records likely represent dispersing individuals from established subpopulations in Eastern Argentina and Southern Brazil.

美洲狮（*Puma concolor*）的地理分布横跨整个美洲大陆，被全球列为无危（Least Concern）物种。但在乌拉圭的潘帕斯草原，美洲狮的保护等级被归类为数据缺乏（Data Deficient），而在阿根廷与巴西则属于区域濒危物种。了解美洲狮的分布与种群现状对其保护工作至关重要。本研究在区域尺度框架下针对乌拉圭草原境内的美洲狮出没情况展开调研，评估其栖息地适宜性并分析近期土地利用变化。本研究采用基于最大熵模型（MaxEnt）的物种分布模型（Species Distribution Model, SDM），使用1999年至2011年间的224条美洲狮观测记录，结合生物气候与地形预测变量开展分析，结果显示潘帕斯草原的栖息地适宜性处于中等水平，表明当地美洲狮种群天然较为稀疏。栖息地适宜性最高的区域集中在河岸与沿河地带。近期的土地利用变化已将大片适宜栖息地转变为难以支撑美洲狮生存的区域，波及乌拉圭境内相当比例的土地。本研究结果表明当地存在源汇动态（source-sink dynamics）：乌拉圭境内的美洲狮观测记录大概率代表了来自阿根廷东部与巴西南部已确立的亚种群的扩散个体。