1. Floods can directly affect riverine organisms by displacing them, and population‐level responses to floods can vary depending on flood magnitude and organism mobility. Benthic organisms can resist displacement until substrates become unstable, whereas mobile organisms are generally more resilient. Freshwater mussels are benthic organisms with low mobility, and there is limited research on their population‐level responses to floods. This study provides novel insights to population‐level responses of mussels to large floods (>500 m³/s).
2. Population dynamics (i.e. abundance, survival, and site fidelity) and sampling efficiency (i.e. detection probability) were estimated in a robust design framework for four freshwater mussel species (Cyclonaias petrina, Cyclonaias pustulosa, Amblema plicata, and Tritogonia verrucosa) from 2017 to 2019 at two sites (upper and lower sites) within riffle habitats in the Colorado River, Texas, U.S.A. Individuals of each species were affixed with shellfish tags, with C. petrina and C. pustulosa individuals also being affixed with passive integrated transponder tags. Changes in population dynamics related to the flood event at each site were directly tested. During sampling, a major flood occurred at each of the two study sites; the floods differed in magnitude but were in the 99th percentile of historical flows at their respective gages.
3. There were site‐ and species‐specific differences in estimated abundances, survival, and site fidelity during periods with the floods. Estimated abundances of C. petrina, C. pustulosa, and T. verrucosa were reduced 40–78% by the lesser flood magnitude (1,283 m³/s) at the upper site. Estimated abundances of C. petrina, C. pustulosa, and A. plicata were reduced 93–95% by the greater flood magnitude (4,332 m³/s) at the lower site. There was a reduction in survival of C. petrina at the upper site, while initially high survival at the lower site was reduced during the interval with the flood for all species. Finally, there was a reduction in site fidelity of C. pustulosa at the lower site.
4. Floods reduced the abundance of all species within riffle habitats at the two sites. Large floods, therefore, affect population dynamics of mussels, but the fate of the displaced mussels is unknown, and with limited inference, reach‐scale effects are unknown. This study adds to the growing body of knowledge about responses of aquatic organisms to large floods, although quantification of recolonisation and fate of displaced mussels are needed to fully understand long‐term effects of large floods on mussel communities.

中文翻译：

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美国淡水贻贝对美国西南部河流洪水的短期响应（使用标记捕获采样估计）

1. 洪水可以通过驱除它们来直接影响河流生物，人口对洪水的反应可能会根据洪水的规模和生物的流动性而变化。底栖生物可以抵抗置换，直到底物变得不稳定为止，而活动生物通常更具弹性。淡水贻贝是底栖生物，流动性低，关于其种群对洪灾的反应研究还很有限。这项研究为贻贝对大洪水（> 500 m ³ / s）的种群水平响应提供了新颖的见解。
2. 在一个稳健的设计框架中，估算了2017年至2019年间四种淡水贻贝物种（Cyclonaias petrina，Cyclonaias pustulosa，Amblema plicata和Tritogonia verrucosa）的种群动态（即丰度，存活率和部位保真度）和采样效率（即检测概率）在美国德克萨斯州科罗拉多河的浅滩栖息地的两个地点（上部和下部地点）上，每个物种的个体都贴有贝类标签，并带有比氏梭菌和脓疱藻个人还贴有无源集成应答器标签。直接测试了与每个站点的洪水事件有关的人口动态变化。在抽样过程中，两个研究地点均发生了大水灾。洪水的规模有所不同，但分别在其历史流量的第99个百分位处。
3. 在洪水期间，估计的丰度，存活率和地点保真度存在特定地点和物种的差异。的估计丰度C. petrina，C.脓疱，和T.疣状是由较小的洪水量级（1283米减少40-78％³在上端站点/秒）。的估计丰度C. petrina，C.脓疱，和A.冠蚌是由更大的洪水量级（4332米减少93-95％³在较低的位点/秒）。梭状芽胞杆菌的生存减少在上游，在整个洪水期间，下游物种的高生存率降低了。最后，较低部位的脓疱假单胞菌的部位保真度降低。
4. 洪水减少了两个地点浅滩栖息地中所有物种的丰度。因此，大洪水会影响贻贝的种群动态，但是流离失所的贻贝的命运尚不得而知，并且通过有限的推断，影响范围的影响是未知的。这项研究增加了有关水生生物对大洪水的反应的知识，尽管要充分了解大洪水对贻贝群落的长期影响，还需要量化重新定殖和贻贝的命运。