边缘效应和保护区内的种群的灭绝
1R. Woodroffe, Department of Zoology, Downing Street, Cambridge CB2 3EJ, UK. J. R. Ginsberg, Wildlife Conservation Society, Bronx, NY 10460-1099, USA.
Science (New York, N.Y.)
|June 26, 1998
概括
小型食肉动物种群面临灭绝的危险不是来自随机的遗传漂移,而是来自保护区边界的人类冲突. 广泛的物种是最脆弱的,无论种群规模如何,突出了需要更广泛的保护战略.
科学领域:
- 生态生态学 生态生态学
- 保护生物学 保护生物学
- 野生动物管理 野生动物管理
背景情况:
- 理论模型预测,由于人口随机性和遗传漂移,小种群很容易灭绝.
- 然而,经验证据表明,种群规模是保护区内大型食肉动物灭绝风险的不充分预测因素.
研究的目的:
- 调查居住在保护区的大型食肉动物种群中灭绝风险的主要驱动因素.
- 为了确定人口数量或其他因素,如人类与野生动物冲突,是灭绝的更重要的预测因素.
主要方法:
- 分析保护区内大型食肉动物种群的死亡原因.
- 评估物种息地大小,暴露在保护区边界和灭绝风险之间的关系.
- 对保护策略有效性的评估仅集中在缓解随机过程上.
主要成果:
- 在保护区边界的人类与野生动物之间的冲突被确定为死亡的主要原因,导致人口下降.
- 拥有更广泛的家园范围的物种不成比例地暴露于边境威胁,并且无论其种群规模如何,都会呈现出更高的灭绝风险.
- 没有解决人类冲突等外部威胁的保护战略不太可能防止灭绝.
结论:
- 大型食肉动物的灭绝风险主要是由外部人为因素驱动的,特别是人类与野生动物之间的冲突,而不是内部的随机过程.
- 保护计划必须优先考虑保护区边界的威胁管理,并考虑物种的空间生态 (家庭范围大小) 以有效保护物种.
- 目前仅关注种群规模和遗传多样性的保护方法可能不足以保护大型食肉动物种群.
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