Fish and crayfish density and count data for Peeks Creek, Macon County, NC, USA 2005-2014, 2019, and 2022 following a catastrophic debris flow, as well as six reference streams

We followed the process of recovery of the fish and crayfish assemblage in Peeks Creek, a high-gradient second order stream in the Little Tennessee River watershed of North Carolina, after a debris flow devastated the channel and its riparian zone. After 15 years, the fish assemblage had recovered, and the channel and riparian zone had stabilized. Of the three major components of the fish assemblage, Rainbow Trout (Oncorhynchus mykiss (Walbaum)), a strong swimmer, reappeared in year 1. Longnose Dace (Rhinichthys cataractae (Valenciennes in Cuvier and Valenciennes)) reappeared in year 3. Mottled Sculpin (Cottus bairdii Girard), a weak swimmer, did not become established until year 6 and only resumed expected abundance in year 9. Appalachian Brook Crayfish (Cambarus bartonii cavatus Hay) numbers recovered quickly, though only one individual was found the year following the debris flow. Unassisted natural recovery occurred after a costly engineered restoration project had been rejected and arguably represents the preferable solution. However, recovery of the fish assemblage may not have been achieved if the stream flowed directly into an impoundment or low gradient river that lacked the source of species for recolonization, or if the stream had been located above a barrier to upstream movement.

本研究追踪了北卡罗来纳州小田纳西河流域内一条高坡度二级溪流——皮克斯溪（Peeks Creek）——在泥石流摧毁河道与滨岸带后，其鱼类与螯虾类群的恢复过程。历经15年监测后，该溪流的鱼类类群已完成恢复，河道与滨岸带也趋于稳定。在鱼类类群的三大主要类群中，游泳能力较强的虹鳟（Rainbow Trout，*Oncorhynchus mykiss* (Walbaum)）于灾后第1年重新出现；长鼻鲦（Longnose Dace，*Rhinichthys cataractae* (Valenciennes in Cuvier and Valenciennes)）于灾后第3年重新出现；而游泳能力较弱的斑鳍杜父鱼（Mottled Sculpin，*Cottus bairdii* Girard）直到灾后第6年才得以定殖，并于第9年才恢复至预期种群丰度。阿巴拉契亚溪螯虾（Appalachian Brook Crayfish，*Cambarus bartonii cavatus* Hay）的种群数量恢复迅速，尽管泥石流发生后的次年仅记录到1只个体。在一项耗资巨大的工程化修复方案被否决后，无人工辅助的自然恢复过程得以实现，且该过程被普遍认为是更优的解决方案。但需注意，若该溪流直接汇入缺乏物种再定殖来源的蓄水水体或低坡度河流，或是其所处位置存在阻碍鱼类向上游移动的屏障，则鱼类类群的恢复可能无法实现。