Data from: Evaluation of acoustic telemetry grids for determining aquatic animal movement and survival

1. Acoustic telemetry studies have frequently prioritized linear configurations of hydrophone receivers, such as perpendicular from shorelines or across rivers, to detect the presence of tagged aquatic animals. This approach introduces unknown bias when receivers are stationed for convenience at geographic bottlenecks (e.g., at the mouth of an embayment or between islands) as opposed to deployments following a statistical sampling design. 2. We evaluated two-dimensional acoustic receiver arrays (grids: receivers spread uniformly across space) as an alternative approach to provide estimates of survival, movement, and habitat use. Performance of variably-spaced receiver grids (5–25 km spacing) was evaluated by simulating (1) animal tracks as correlated random walks (speed: 0.1–0.9 m/s; turning angle standard deviation: 5–30 degrees); (2) variable tag transmission intervals along each track (nominal delay: 15–300 seconds); and (3) probability of detection of each transmission based on logistic detection range curves (midpoint: 200–1500 m). From simulations, we quantified i) time between successive detections on any receiver (detection time), ii) time between successive detections on different receivers (transit time), and iii) distance between successive detections on different receivers (transit distance). 3. In the most restrictive detection range scenario (200 m), the 95th percentile of transit time was 3.2 days at 5 km grid spacing, 5.7 days at 7 km, and 15.2 days at 25 km; for the 1500 m detection range scenario, it was 0.1 days at 5 km, 0.5 days at 7 km, and 10.8 days at 25 km. These values represented upper bounds on the expected maximum time that an animal could go undetected. Comparison of the simulations with pilot studies on three fishes (walleye Sander vitreus, common carp Cyprinus carpio, and channel catfish Ictalurus punctatus) from two independent large lake ecosystems (lakes Erie and Winnipeg) revealed shorter detection and transit times than what simulations predicted. 4. By spreading effort uniformly across space, grids can improve understanding of fish migration over the commonly employed receiver line approach, but at increased time cost for maintaining grids.1. 声学遥测（acoustic telemetry）研究通常优先采用水听器接收机（hydrophone receivers）的线性布设方案，例如沿海岸线垂直布设或跨河布设，以检测携带标记的水生动物的活动。若为便利起见，将接收机部署在地理瓶颈区域（如海湾入口或岛屿间），而非遵循统计抽样设计进行布设，则该方法会引入未知偏差。 2. 本研究将二维声学接收机阵列（two-dimensional acoustic receiver arrays，即接收机在空间内均匀布设的网格）作为替代方案，用于估算水生动物的存活率、移动模式与栖息地利用情况。我们通过模拟场景对间距为5~25 km的可变间距接收机网格的性能进行评估：(1) 将动物运动轨迹建模为相关随机游走（correlated random walks，运动速度：0.1~0.9 m/s；转向角标准差：5~30度）；(2) 为每条轨迹设置可变的标记发射间隔（标称延迟：15~300秒）；(3) 基于逻辑斯蒂检测范围曲线（logistic detection range curves，中点值：200~1500 m）设定单次发射的检测概率。通过模拟实验，我们量化了三项指标：i) 任意接收机上连续两次检测的时间间隔（检测时间），ii) 不同接收机间连续两次检测的时间间隔（过境时间），以及iii) 不同接收机间连续两次检测的空间距离（过境距离）。 3. 在最严格的检测范围场景（200 m）下，当网格间距为5 km时，过境时间的95分位数为3.2天，7 km间距时为5.7天，25 km间距时为15.2天；而在1500 m检测范围场景下，对应值分别为0.1天（5 km）、0.5天（7 km）和10.8天（25 km）。上述数值代表了动物未被检测到的预期最长时间上限。将模拟结果与两项针对两大独立湖泊生态系统——伊利湖（Erie）与温尼伯湖（Winnipeg）——中三种鱼类：大眼梭鲈（Sander vitreus）、鲤（Cyprinus carpio）以及斑真鮰（Ictalurus punctatus）的预实验结果进行对比后发现，实际检测时间与过境时间均短于模拟预测值。 4. 相较于常规采用的接收机线性布设方案，空间均匀布设的网格阵列能够提升对鱼类洄游行为的认知，但同时也会增加网格维护的时间成本。