Influence of water temperature and streambed stability on the abundance and distribution of slimy sculpin (Cottus cognatus)
Influence of water temperature and streambed stability on the abundance and distribution of slimy sculpin (Cottus cognatus)
复制标题
水温和河床稳定性对泥杜父鱼(Cottus cognatus)丰度和分布的影响
DOI：
--
复制
发表时间：
2007
影响因子：
1.4
通讯作者：
R. Cunjak
中科院分区：
文献类型：
--
作者：
Patricia A. Edwards;R. Cunjak
杜父鱼是体型较小的鱼类，活动能力有限。因此，这些鱼类可能是环境影响监测中哨兵物种的理想选择，因为它们比历史上用于监测项目的体型较大、分布范围更广的物种更能反映当地的环境条件。这项研究量化了新不伦瑞克省双体溪的粘杜父鱼（Cottus cognatus）种群的时空密度和分布模式，目的是更好地了解它们对自然环境变化的反应。我们预测杜父鱼密度将遵循从源头到河口的纵向温度梯度，并且对溪流波动和底质扰动高度敏感。 1991年至1998年每年进行两次的电捕鱼调查显示，杜父鱼密度在年份、河段和栖息地之间存在显着差异，但在季节之间没有显着差异。在夏季水温最凉爽的河段发现了最高的杜父父鱼密度。双体溪的中游每年支持最高的杜父鱼密度，其次是源头或上游，然后是两个最下游的河段：峡谷和下游。随机事件也影响人口动态。仲冬冰崩（1996年）及其相关的洪水和冰冲刷对杜父鱼种群造成了最大的干扰，导致密度显着下降和种群年龄结构的变化。为进一步评估杜父父鱼对基质稳定性的反应而进行的底质移动实验发现，河流上游和中游的底质稳定性高于下游。本研究中观察到的杜父父鱼分布模式与杜父父父鱼的分布和丰度受溪流温度影响显着，但也部分受河床稳定性影响的观点一致。
Sculpin are small-bodied fish that exhibit limited mobility. These fish may therefore be an ideal choice as sentinel species in environmental effects monitoring as they may be more reflective of ambient local conditions than are the large-bodied, more wide-ranging species historically used in monitoring programs. This study quantified the spatial and temporal density and distributional patterns of the slimy sculpin (Cottus cognatus) population in Catamaran Brook, New Brunswick, with the aim of gaining a better understanding of their response to natural environmental variability. We predicted that sculpin densities would follow a longitudinal temperature gradient from headwater to mouth and would be highly sensitive to fluctuations in stream flow and substrate disturbance. Electrofishing surveys conducted twice per year from 1991 to 1998 revealed significant differences in sculpin density between years, reaches, and habitats, but not between seasons. The highest sculpin densities were found in those reaches with the coolest summer water temperature. The Middle reach in Catamaran Brook annually supported the highest sculpin density, followed by the headwater or Upper reach and then by the two lowermost reaches: Gorge and Lower. Stochastic events also influenced population dynamics. A mid-winter ice break-up (1996) and its associated flood and ice scour caused the greatest disturbance of the sculpin population, resulting in a significant density decline and a shift in the population age structure. A bedload movement experiment conducted to further assess sculpins’ response to substrate stability identified greater bed stability in the Upper and Middle reaches of the brook than in the Lower reach. The pattern of sculpin distribution observed in this study is consistent with the idea that distribution and abundance of sculpin are significantly influenced by stream temperature but also, in part, by stream bed stability.