The use of stereo camera systems to measure fish body size has gained attention in aquaculture systems management. However, the different correlations between swimming depth and size according to fish species can lead to measurement bias depending on camera range and position. This study accordingly applied a fish behavior model based on the Boid model to simulate the relationship among camera position, viewing range, and measurement results considering swimming depth behavior. A total of 722 simulated fish (yellowtail Seriola quinqueradiata) were placed into a rectangular aquaculture net pen model. Virtual cameras were located at different depths along the side, above, and below the pen to measure the total length of individual fish within view. Horizontally oriented cameras closer to the surface captured significantly larger/smaller individuals when the behavior model assumed that larger individuals swim at shallower/deeper depths; vertically oriented cameras facing down from the water surface or up from the bottom net provided mean total length measurements might close to the actual mean total length of the population when a wide viewing range was provided. The proposed simulation method can be applied to preliminarily evaluate the measurement biases inherent to fish behavior and thereby minimize their influence on camera measurements.

使用立体摄像系统测量鱼类体型已在水产养殖系统管理中引起关注。然而，根据鱼类种类，游泳深度和大小之间的不同相关性可能会导致测量偏差，具体取决于相机范围和位置。因此，本研究应用基于Boid模型的鱼类行为模型来模拟考虑游泳深度行为的相机位置、观看范围和测量结果之间的关系。将722条模拟鱼（鰤鱼Seriola quinqueradiata）放入矩形水产养殖网围栏模型中。虚拟摄像机位于围栏侧面、上方和下方的不同深度，以测量视野内单条鱼的总长度。当行为模型假设体型较大的个体在较浅/较深的深度游泳时，靠近水面的水平方向摄像机会捕获明显较大/较小的个体；当提供较宽的观看范围时，垂直方向的摄像机从水面向下或从底部网向上，提供的平均总长度测量结果可能接近人群的实际平均总长度。该仿真方法可用于初步评估鱼类行为固有的测量偏差，从而最大限度地减少其对相机测量的影响。