Harris Grant M, Stewart David R, Butler Matthew J, Rominger Eric M, Ruhl Caitlin Q, McDonald Daniel T, Schmidt Paige M
United States Fish and Wildlife Service, Albuquerque, NM, USA.
New Mexico Department of Game and Fish (Retired), Santa Fe, NM, USA.
Sci Rep. 2024 Dec 28;14(1):31421. doi: 10.1038/s41598-024-83011-4.
Abundance estimates inform ungulate management and recovery efforts. Yet effective and affordable estimation techniques remain absent for most ungulates lacking identifiable marks and inhabiting rugged or highly vegetated terrain. Methods using N-mixture models with camera trap imagery form an appealing solution but remain unvalidated. We assess this method using populations of desert bighorn sheep (DBS; Ovis canadensis) in New Mexico, USA, plus bison (Bison bison bison) and Texas longhorn cattle (Bos taurus taurus) in Oklahoma, USA, by calculating and comparing abundance estimates to censused values. We parsed data by 3 and 7-day intervals, using images filtered or unfiltered, and collected with motion detection or timed camera settings. We employed priors informed by subject matter experts (SME) and calculated using detection-nondetection methods. Abundance estimates from filtered images captured by motion detection in 3-day intervals included the censused value across all seasons for adult DBS, rams and ewes, indicating "best practices". This "best practices" method also captured censused values for population estimates of bison (detection-nondetection) and cattle with both priors. Our assessment validates the use of N-mixture with camera trap imagery, while presenting sampling approaches, data handling procedures and model calibration to estimate wildlife population sizes more appropriately and accurately.
数量估计为有蹄类动物的管理和恢复工作提供了依据。然而，对于大多数没有可识别标记且生活在崎岖或植被茂密地区的有蹄类动物来说，仍然缺乏有效且经济实惠的估计技术。使用带相机陷阱图像的N - 混合模型的方法是一个有吸引力的解决方案，但尚未得到验证。我们通过计算并将数量估计值与普查值进行比较，对美国新墨西哥州的沙漠大角羊（DBS；加拿大盘羊）种群，以及美国俄克拉荷马州的野牛（美洲野牛指名亚种）和德克萨斯长角牛（黄牛指名亚种），评估了这种方法。我们按3天和7天的间隔对数据进行解析，使用经过过滤或未过滤的图像，这些图像通过运动检测或定时相机设置收集。我们采用了由主题专家（SME）提供信息并使用检测 - 非检测方法计算得出的先验值。以3天为间隔通过运动检测捕获的过滤图像得出的数量估计值包括了所有季节成年DBS、公羊和母羊的普查值，这表明了“最佳实践”。这种“最佳实践”方法还通过两种先验值捕获了野牛（检测 - 非检测）和牛种群估计的普查值。我们的评估验证了N - 混合模型与相机陷阱图像的使用，同时展示了采样方法、数据处理程序和模型校准，以便更合适、准确地估计野生动物种群数量。
