Data from: Integrating niche and occupancy models to infer the distribution of an endemic fossorial snake (Atractus lasallei)

Understanding species distribution and habitat preferences is crucial for effective conservation strategies. However, the lack of information about population responses to environmental change at different scales hinders effective conservation measures. In this study, we estimate the potential and realized distribution of Atractus lasallei, a semi-fossorial snake endemic to the northwestern region of Colombia. We modelled the potential distribution of A. lasallei based on ecological niche theory (using maxent), and habitat use was characterized while accounting for imperfect detection using a single-season occupancy model. Our results suggest that A. lasallei selects areas characterized by slopes below 10°, with high average annual precipitation (>2500mm/year) and herbaceous and shrubby vegetation. Its potential distribution encompasses the northern Central Cordillera and two smaller centers along the Western Cordillera, but its habitat is heavily fragmented within this potential distribution. When the two models are combined, the species' realized distribution sums up to 935 km2, highlighting its vulnerability. We recommend approaches that focus on variability at different spatio-temporal scales to better comprehend the variables that affect species' ranges and identify threats to vulnerable species. Prompt actions are needed to protect herbaceous and shrub vegetation in this region, highly demanded for agriculture and cattle grazing.明晰物种分布与栖息地偏好，对于制定高效的保护策略至关重要。然而，当前缺乏不同空间尺度下种群对环境变化响应的相关数据，这一短板制约了保护措施的落地实效。本研究旨在评估哥伦比亚西北部特有半穴居蛇类Atractus lasallei的潜在分布与实际分布范围。基于生态位理论，我们采用最大熵（MaxEnt）模型构建了A. lasallei的潜在分布预测模型；同时通过单季占用模型，在考虑检测不完全性的前提下对其栖息地利用特征进行了系统刻画。研究结果显示，该蛇类偏好坡度低于10°、年平均降水量超2500毫米、兼具草本与灌丛植被的区域。其潜在分布涵盖中科迪勒拉山脉北段，以及西科迪勒拉山脉沿线的两处小型分布核心区，但在该潜在分布范围内，其栖息地已遭到严重破碎化。将两类模型结合分析后，该物种的实际分布总面积仅为935平方千米，凸显了其生存脆弱性。我们建议未来研究应聚焦不同时空尺度下的环境变量变异，以更深入解析影响物种分布范围的驱动因子，并明确威胁脆弱物种生存的各类风险。该区域的草本与灌丛植被因农业与畜牧活动需求正面临高强度开发，亟需采取紧急措施加以保护。