Colonization of a temperate river by mobile fish following habitat reconnection
Colonization of a temperate river by mobile fish following habitat reconnection
复制标题
栖息地重新连接后，流动鱼类在温带河流中定居
DOI：
10.1002/ecs2.4336
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发表时间：
2023
期刊：
影响因子：
2.7
通讯作者：
T. Quinn
中科院分区：
文献类型：
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作者：
P. Kiffney;P. Lisi;M. Liermann;S. Naman;J. Anderson;M. Bond;G. Pess;M. Koehler;E. Buhle;T. Buehrens;R. Klett;J. Cram;T. Quinn
流动物种尤其受到人为障碍的影响，人为障碍需要大量投资才能恢复连接。然而，很少有大规模、长期的研究调查这些物种恢复连通性的生态后果。我们的研究跨越15-20 年，量化了三种本地鲑鱼在2003年华盛顿州锡达河兰茨堡大坝恢复鱼类通道后定居在20 公里受保护栖息地的响应轨迹，这些轨迹代表了干扰后的时间趋势。这座大坝建于1901年，在102年的 时间里，阻止了当地顺水而上的鳕鱼、奇努克鲑鱼和非顺水而上的山地白鱼的上游活动。还通过比较雪松河幼体Coho和Chinook鲑鱼在恢复到附近未筑坝的次流域后淡水生产力的时间趋势来评估恢复效果。我们还比较了夏季幼年Coho和Chinook鲑鱼的密度，以及大坝上方的山地白鱼在恢复到未筑坝的参考系统十年后测量的密度。恢复后，淡水型鲑鱼和非淡水型山地白鱼种群呈线性或非线性增长。成体奇努克鲑鱼数量所代表的积极、渐近的反应表明种群恢复速度放缓，在恢复十年后趋于平稳。相比之下，成年Coho鲑鱼的年丰度以恒定的速度增加，这表明恢复15 后的容量有所增加。鲑鱼的组成多样性在很大程度上是由幼鲑鱼推动的，也呈非线性增加，在十年内趋于平稳。我们观察到了时间响应的巨大空间变化，因为幼鱼Coho鲑鱼和山地白鱼种群的扩张随着距离恢复地点的上游距离线性放缓。有证据表明，夏季鲑鱼生物量的一些年变化是冬季和春季流量变化的结果，随着流量变化的增加，生物量下降。在恢复之前，物种的重新引入和建立对大坝上方的溪流养殖鲑鱼没有明显的影响，但增加了次流域尺度上的Coho淡水生产力。我们的研究结果表明，三个流动物种的再繁殖至少需要十年或更长时间，每个物种都有独特的生活史，这取决于物种和生命阶段、产卵种群的大小、离恢复地点的距离以及径流的年变化。
Mobile species are particularly affected by artificial barriers requiring large investments to restore connectivity. However, few large‐scale, long‐term studies have investigated the ecological outcomes of restoring connectivity for these species. Our study, spanning 15–20 years, quantified response trajectories, which represent temporal trends following disturbance, of three native salmonids colonizing 20 km of protected habitat following restoration of fish passage at Landsburg Dam, Cedar River, WA, in 2003. Built in 1901, the dam blocked the upriver movement of native anadromous coho and Chinook salmon and nonanadromous mountain whitefish for 102 years. Restoration effectiveness was also assessed by comparing temporal trends in freshwater productivity of juvenile coho and Chinook salmon in the Cedar River after restoration to a nearby undammed subbasin. We also compared summer densities of juvenile coho and Chinook salmon, and mountain whitefish above the dam measured a decade after restoration to undammed reference systems. Anadromous salmon and nonanadromous mountain whitefish populations increased linearly or nonlinearly following restoration. The positive, asymptotic response represented by adult Chinook salmon counts indicates a slowing in population recovery rate, plateauing a decade after restoration. In contrast, annual abundance of adult coho salmon increased at a constant rate, indicating additional capacity 15 years post‐restoration. Salmonid compositional diversity, driven largely by juvenile coho salmon, also increased nonlinearly, plateauing in a decade. We observed substantial spatial variation in the temporal response, as juvenile coho salmon and mountain whitefish population expansion slowed linearly with upstream distance from the restoration site. There was evidence that some of the annual variation in salmonid biomass in summer was a result of discharge variability in winter and spring, with biomass declining as flow variability increased. Species reintroduction and establishment had no discernible effect on stream‐rearing salmonids living above the dam before restoration, while increasing coho freshwater productivity at the subbasin scale. Results from our study showed recolonization by three mobile species, each with a unique life history, takes at least a decade or more and was dependent on species and life stage, size of the spawning population, distance from restoration site, and annual variability in streamflow.