在干旱的草食群落中,自下而上的空间使用与自上而下的时间风险缓冲
John Heydinger1,2, Uakendisa Muzuma3,4, Tammy Hoth-Hanssen5
1Savannah River Ecology Laboratory University of Georgia Aiken South Carolina USA.
Ecology and evolution
|January 6, 2026
概括
在干旱的系统中,大型食草动物平衡了资源需求与避免捕食者的需求. 他们最大限度地减少了与夜间捕食者的活动重叠,对捕食风险表现出特征依赖的空间反应.
科学领域:
- 生态生态学 生态生态学
- 行为生态学 行为生态学
- 保护生物学 保护生物学
背景情况:
- 恐惧景观 (LOF) 框架解释了猎物的行为,以应对掠食风险.
- 它在资源有限,没有围的干旱生态系统中的应用,具有多种捕食者和猎物物种,并未得到充分理解.
- 大型食草动物面临环境约束和掠食压力之间的复杂相互作用.
研究的目的:
- 为了研究一个没有围的干旱系统中的大型食草动物如何应对环境限制和掠食风险.
- 测试关于自下而上 (资源) 和自上而下 (掠食者) 因素对草食动物空间使用和时间活动的相对影响的假设.
- 为干旱,多掠食者环境完善LOF框架.
主要方法:
- 利用了纳米比亚西北部的摄像头陷数据.
- 检查了七种大型食草动物物种 (金牛,长鹿,库杜,斑马,春,黑犀牛,大象) 的空间使用和迪尔活动模式.
- 评估了来自狮子和斑点的掠食风险,并纳入了干旱季节的进展和息地结构等环境变量.
主要成果:
- "自下而上的环境约束是草食动物利用空间的主要驱动因素,而不是捕食者的存在.
- 草食动物主要减少了与夜间捕食者的时间重叠,保持了白天活动模式 (Δ ≈0.06-0.26).
- 对捕食者的空间反应取决于背景,并受到环境因素的调节,这表明时间空间的可塑性.
结论:
- 在干旱,没有围的系统中,草食动物的行为是分层结构的,资源管理空间使用,捕食者影响时间活动.
- 在这些景观中,猎物种优先考虑时间分区,而不是空间避开捕食者.
- 该研究建议对LOF框架进行修改,以更好地考虑到干旱生态系统中的资源限制和多种掠食者.
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