Patch size but not short‐term isolation influences occurrence of westslope cutthroat trout above human‐made barriers
Patch size but not short‐term isolation influences occurrence of westslope cutthroat trout above human‐made barriers
复制标题
斑块大小而非短期隔离影响西坡切喉鳟鱼在人造屏障上方的出现
DOI：
10.1111/eff.12108
复制
发表时间：
2014
影响因子：
1.8
通讯作者：
M. Young
中科院分区：
文献类型：
--
作者：
Douglas P. Peterson;B. Rieman;Dona L. Horan;M. Young
水生系统中的栖息地破碎化导致了溪流鱼类的广泛隔离。集合种群理论预测，持久性是直接相关的地方补丁大小和它的特点，但因为这些关系往往是分类特定的，经验数据是很重要的。我们收集了246个观察发生的westslope cutthroat鳟鱼（WCT），在美国西部和加拿大的关注分类，在流网络隔离长达100年（中位数40年）以上的人为障碍，主要是涵洞，在美国国家森林的道路交叉口。我们使用逻辑回归分析如何WCT发生与斑块大小，隔离时间和流级协变量的变化。发生率呈正相关的流长度和栖息地质量内孤立的河流网络和负相关的海拔和通道坡度。出乎意料的是，发生的概率是不相关的多久栖息地补丁已被隔离。在中位海拔（1354米）和通道梯度（14%），生境质量差，WCT很可能发生（概率>0.5），如果一个孤立的河流网络是至少1.7公里。如果栖息地质量高，约0.2公里的栖息地产生相同的概率。虽然有重要的限制，本分析提供了第一个经验估计补丁大小和补丁级特性如何影响持续性的WCT在孤立的流网络。
Habitat fragmentation in aquatic systems has led to widespread isolation of stream fishes. Metapopulation theory predicts that persistence is directly related to local patch size and its characteristics, but because these relationships tend to be taxon-specific, empirical data are important. We assembled 246 observations of occurrence of westslope cutthroat trout (WCT), a taxon of concern in the western U.S. and Canada, in stream networks isolated for up to 100 years (median 40 years) above human-made barriers, mostly culverts, at road crossings within U.S. National Forests. We used logistic regression to analyse how WCT occurrence varied with patch size, isolation time and stream-level covariates. Occurrence was positively related to stream length and habitat quality within the isolated stream network and negatively related to elevation and channel gradient. Unexpectedly, the probability of occurrence was not related to how long a habitat patch had been isolated. At the median elevation (1354 m) and channel gradient (14%), and where habitat quality was poor, WCT were likely to occur (probability >0.5) if an isolated stream network was at least 1.7 km. If habitat quality was high, about 0.2 km of habitat produced the same probability. Although there are important limitations, this analysis provides the first empirical estimate for how patch size and patch-level characteristics influence persistence of WCT in isolated stream networks.
DOI：
--
发表时间：
2015-10
期刊：
--
影响因子：
--
作者：
Douglas M. Bates;M. Maechler;Ben Bolker;Steven C. Walker
通讯作者：
Douglas M. Bates;M. Maechler;Ben Bolker;Steven C. Walker
影响因子：
56.9
作者：
LANDE, R
通讯作者：
LANDE, R