Escaped farmed Atlantic salmon Salmo salar interbreeding with wild conspecifics represents a threat to the genetic integrity and viability of wild populations. Therefore, it is necessary to accurately quantify escapees in riverine systems to monitor and mitigate interactions with wild conspecifics. Drift diving surveys are presently used in Norway to quantify the number of wild and escaped farmed salmon in rivers. However, limited information is available on the validity of the method for distinguishing escapees from wild conspecifics. Comparing the proportion of escapees calculated from drift diving (mean = 8.5%) and net captures (mean = 8.6%), we found that drift diving was well correlated with net captures (adj. r2 = 0.79). Furthermore, scale analysis from an independent data set demonstrated a 98% true positive rate when identifying and capturing farmed escapees during drift diving. The results of this study indicate that drift diving is an accurate and robust method for quantifying escaped farmed salmon, at least in rivers where observation conditions are adequate for snorkeling. In general, drift diving can be a valuable tool for stakeholders to quickly assess broad spatial extents with limited time and resources.

中文翻译：

---

与鱼一起游泳：验证漂流潜水以识别野外养殖的大西洋鲑鱼逃逸者

逃逸的养殖大西洋鲑鱼与野生同种杂交对野生种群的遗传完整性和生存能力构成威胁。因此，有必要准确量化河流系统中的逃逸者，以监测和减轻与野生同种动物的相互作用。挪威目前使用漂流潜水调查来量化河流中野生和逃逸的养殖鲑鱼的数量。然而，关于区分逃逸者和野生同种物种的方法有效性的信息有限。比较从漂流潜水（平均值 = 8.5%）和净捕获（平均值 = 8.6%）计算的逃逸者比例，我们发现漂流潜水与净捕获（调整 r2 = 0.79）密切相关。此外，来自独立数据集的规模分析表明，在漂流潜水期间识别和捕获养殖逃生者时，真阳性率为 98%。这项研究的结果表明，漂流潜水是一种准确而可靠的方法，可以量化逃逸的养殖鲑鱼，至少在观测条件适合浮潜的河流中是这样。一般来说，漂流潜水可以成为利益相关者以有限的时间和资源快速评估广阔空间范围的宝贵工具。