Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia.
PLoS One. 2011 Apr 21;6(4):e18965. doi: 10.1371/journal.pone.0018965.
Diver-based Underwater Visual Censuses (UVCs), particularly transect-based surveys, are key tools in the study of coral reef fish ecology. These techniques, however, have inherent problems that make it difficult to collect accurate numerical data. One of these problems is the diver effect (defined as the reaction of fish to a diver). Although widely recognised, its effects have yet to be quantified and the extent of taxonomic variation remains to be determined. We therefore examined relative diver effects on a reef fish assemblage on the Great Barrier Reef. Using common UVC methods, the recorded abundance of seven reef fish groups were significantly affected by the ongoing presence of SCUBA divers. Overall, the diver effect resulted in a 52% decrease in the mean number of individuals recorded, with declines of up to 70% in individual families. Although the diver effect appears to be a significant problem, UVCs remain a useful approach for quantifying spatial and temporal variation in relative fish abundances, especially if using methods that minimise the exposure of fishes to divers. Fixed distance transects using tapes or lines deployed by a second diver (or GPS-calibrated timed swims) would appear to maximise fish counts and minimise diver effects.
基于潜水员的水下目视普查（UVC），特别是基于横切的调查，是珊瑚礁鱼类生态学研究的重要工具。然而，这些技术存在固有的问题，使得难以收集准确的数值数据。其中一个问题是潜水员效应（定义为鱼类对潜水员的反应）。尽管这一效应已被广泛认可，但尚未对其进行量化，并且分类群的变异程度仍有待确定。因此，我们研究了大堡礁上一个珊瑚礁鱼类群落的相对潜水员效应。使用常见的 UVC 方法，记录到的七种珊瑚礁鱼类群体的丰度受到 SCUBA 潜水员持续存在的显著影响。总体而言，潜水员效应导致记录的个体数量平均减少了 52%，个别鱼类家族的降幅甚至高达 70%。尽管潜水员效应似乎是一个严重的问题，但 UVC 仍然是一种有用的方法，可以量化相对鱼类丰度的空间和时间变化，特别是如果使用最小化鱼类暴露于潜水员的方法。使用第二潜水员部署的胶带或线（或经过 GPS 校准的定时游泳）进行固定距离横切似乎可以最大限度地增加鱼类计数并最小化潜水员效应。
