在森林干扰后,在连续的时间尺度上,鹿资源选择的密度取决于变化
Joel Ruprecht1, Michael J Wisdom2, Darren A Clark3
1Department of Fisheries, Wildlife, and Conservation Sciences, Oregon State University, Corvallis, Oregon, USA.
概括
鹿在夜间使用伐木区域寻找食物,但在白天避开它们,这表明息地扰乱的好处因人口密度和时间而异. 这凸显了需要多样化的森林结构来支持大型食草动物的需要.
科学领域:
- 生态生态学 生态生态学
- 野生动物管理 野生动物管理
- 林业林业 林业 林业 林业
背景情况:
- 像伐木这样的景观干扰改变了息地结构和草食动物的料供应.
- 草食动物对息地变化的反应可能是复杂的,受料,覆盖面和人口密度的影响.
- 了解干扰的长期生态影响需要研究在相继的时间尺度上的反应.
研究的目的:
- 量化鹿 (Cervus canadensis) 空间使用在木材采伐后在每日,每月和连续时间尺度上的变化.
- 调查人口密度对鹿对伐木息地的反应的影响.
- 评估息地修改对大型草食动物行为影响的持续性.
主要方法:
- 利用30年的远程测量数据从鹿种群在两个不同的密度.
- 分析了白天 (diel) 的不同时间,几个月的空间使用模式,以及记录后的连续时期.
- 采伐与未采伐森林面积的比较选择和避免.
主要成果:
- 鹿在夜间选择了砍伐的区域,收获后14年使用的峰值,持续超过26年,表明利用了改进的料.
- 低密度鹿种群的选择幅度高出73%,与理想的自由分布预测保持一致.
- 鹿在白天避免了长达28年的伐木地区,更喜欢完整的森林,这表明需要掩护其他生命历史要求.
结论:
- 景观干扰可以在连续的时间尺度上增强大型食草动物的食机会,但好处取决于密度.
- 持续的白天避开伐木区域强调了森林覆盖面对的关键作用.
- 森林斑块的马赛克具有不同的连续阶段和结构完整性,可能是大型食草动物的最佳选择.
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