揭示主要生产者与顶级掠食者之间的杂食和社区互动
Ashlee J Mikkelsen1, Andreas Zedrosser1,2, Agnieszka Sergiel3
1Department of Natural Sciences and Environmental Health University of South-Eastern Norway Borre Vestfold-Telemark Norway.
Ecology and evolution
|April 8, 2025
概括
在瑞典,棕熊的饮食受果的可用性影响,而不仅仅是猎物. 了解植物性食物来源对于预测捕食者对气候变化的反应至关重要.
科学领域:
- 生态生态学 生态生态学
- 气候变化生物学 气候变化生物学
- 野生动物生态生态学
背景情况:
- 气候和植物现象学的变化会影响草食动物的饮食,但捕食者的反应,特别是对植物成分的反应,研究较少.
- 捕食者的饮食往往过于简单化,只专注于猎物,忽视了植物等其他食物来源.
- 杂食物种在生态系统中扮演着复杂的角色,不仅仅是掠食.
研究的目的:
- 为了研究棕熊 (Ursus arctos) 的长期饮食模式.
- 为了确定影响棕熊饮食组成年度变化的因素.
- 评估粮食可用性的影响,包括植物和猎物资源,对棕熊的食行为.
主要方法:
- 利用瑞典棕熊的长期,基于个人的数据集.
- 使用碳和稳定同位素分析头发样本以确定饮食.
- 应用贝叶斯混合模型和线性混合模型来分析饮食成分并将其与食品可用性指数联系起来.
主要成果:
- 棕熊的饮食变化在很大程度上是由蓝 (Vaccinium myrtillus) 的生产力解释的.
- 尽管鹿数量增加,但鹿在熊的饮食中所占的比例并没有增加.
- 饮食中蓝的比例呈现出越来越多的变化,而鹿的比例随着时间的推移略有下降.
结论:
- 在瑞典,棕熊的饮食成分是响应植物性食物可用性的变化 (白),不管猎物是否可用.
- 植物性饮食成分对于理解捕食者生态和对环境变化的反应至关重要.
- 未来的气候变化影响评估必须强调各种食物来源在捕食者饮食中的作用,以准确地进行生态预测.
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