Randolph John F, Young Julie K, Stoner David C, Garcelon David K
Department of Wildland Resources Utah State University Logan Utah USA.
Ecology Center Utah State University Logan Utah USA.
Ecol Evol. 2024 Aug 1;14(8):e70097. doi: 10.1002/ece3.70097. eCollection 2024 Aug.
Dispersal is a complex series of movements before an individual establishes a home range. Animals must travel and forage in unfamiliar landscapes that include anthropogenic risks such as road crossings, harvest, and urban landscapes. We compare dispersal behavior of juvenile mountain lions () from two geographically distinct populations in California and Nevada, USA. These two sites are ecologically similar but have different management practices; hunting is permitted in Nevada, whereas mountain lions are protected in California. We used GPS-collar data and net-squared displacement analysis to identify three dispersal states: exploratory, departure, and transient home range. We then compared each dispersal state of the two mountain lion populations using an integrated step selection analysis (iSSA). The model included explanatory variables hypothesized to influence one or more dispersal states, including distance to forest, shrub, water, hay and crop, developed lands, and four-wheel drive roads, as well as elevation and terrain ruggedness. Results revealed consistent habitat selection between sites across most landscape variables, with one notable exception: anthropogenic covariates, including distance to developed land, distance to hay and crop, and distance to four-wheeled drive roads, were only statistically significant on modeled habitat selection during dispersal in the population subject to hunting (i.e., Nevada). Results suggest that hunting (pursuit with hounds resulting in harvest) and non-lethal pursuit (pursuit with hounds but no harvest allowed) increase avoidance of anthropogenic landscapes during dispersal for juvenile mountain lions. By comparing populations, we provided valuable insights into the role of management in shaping dispersal behavior.
扩散是个体建立活动范围之前一系列复杂的移动过程。动物必须在陌生的景观中移动和觅食，这些景观包括诸如穿越道路、收获活动和城市景观等人为风险。我们比较了来自美国加利福尼亚州和内华达州两个地理上不同种群的幼年美洲狮（）的扩散行为。这两个地点在生态上相似，但管理方式不同；内华达州允许狩猎，而加利福尼亚州则保护美洲狮。我们使用GPS项圈数据和净平方位移分析来识别三种扩散状态：探索性、离开和临时活动范围。然后，我们使用综合步长选择分析（iSSA）比较了两个美洲狮种群的每种扩散状态。该模型包括假设会影响一种或多种扩散状态的解释变量，包括到森林、灌木、水源、干草和作物、已开发土地以及四轮驱动道路的距离，还有海拔和地形崎岖度。结果显示，在大多数景观变量方面，两个地点之间的栖息地选择是一致的，但有一个显著例外：人为协变量，包括到已开发土地的距离、到干草和作物的距离以及到四轮驱动道路的距离，仅在受狩猎影响的种群（即内华达州）扩散期间的模拟栖息地选择中具有统计学显著性。结果表明，狩猎（用猎犬追捕并导致捕杀）和非致命追捕（用猎犬追捕但不允许捕杀）会增加幼年美洲狮在扩散期间对人为景观的回避。通过比较不同种群，我们为管理在塑造扩散行为中的作用提供了有价值的见解。
