Reef fish abundance raw data

In 2013, reef fish community was accessed by visual census using lineal transects of 50 m. For the shallow depths (0-8 m, 9-15 m, 16-22 m, 24-30 m), the transects were extended in four directions (north, south, east and west) from the center of the sample area, for an area of 200 m². The data was registered at two meters of distance from each side of the transect, where all fish individuals were recorded. The deepest transects (34-40 m, 44-50 m, 54-60 m, 64-70 m) were extended in one direction with an area of 50 m², due to the geomorphology of the diapiric domes and restrictions of dive time. The shallow ranges of depth were made in 14 sites and the deep ranges in 3 of the 14 sites sampled. To avoid oversampling by the two observers, when an individual was crossing at the same time in the range of vision, only one of the observers counted the individual. Data was analyzed calculating the abundance per m² due to the differences in the total areas sampled between shallow and deepest zones (See main manuscript).

2013年，研究人员采用50米直线样带（lineal transects）法开展目视普查（visual census），对礁鱼群落进行调查。针对浅水深层（0~8 m、9~15 m、16~22 m、24~30 m），样带从样地中心向北、南、东、西四个方向延伸，单样地覆盖面积为200平方米。样带两侧各2米范围内的所有鱼类个体均被记录在册。由于底辟穹丘（diapiric domes）的地貌特征与潜水时长限制，最深层样带（34~40 m、44~50 m、54~60 m、64~70 m）仅沿单一方向布设，单样地覆盖面积为50平方米。本次采样共设置14个浅水深层样点，深层样点则为14个采样样点中的3个。为避免两名观测者出现重复计数的情况，当某一鱼类个体同时处于两名观测者的视野范围内时，仅由一名观测者记录该个体。鉴于浅水区与深水区的总采样面积存在差异，研究通过计算单位面积丰度（abundance per m²）对数据进行分析（详见主文稿）。