Channel Islands OPC: Subtidal: Community Surveys: Fish Survey

This metadata record documents the fish surveys for PISCO subtidal community surveys. Fish sampling consists of recording the number and size of all non-cryptic fishes on "transects". At each sampling location "bottom," "mid-water," and "canopy" transects are surveyed. Dimensions for all transects are 2m x 2m x 30m. Subtidal community structure surveys are conducted annually at all sites during the summer or early fall, and quantify substrate type and relief, benthic cover, abundance of major groups of macroalgae and invertebrates, and abundance and size of fishes. Spatial allocation of sampling is designed to measure year-to-year site-wide variability in community structure and the spatial scales at which such variation occurs. A site is defined as a fixed stretch of coastline, occupying approximately 500m. Originally, each site was divided into 2 halves (sides), each comprised of 12 transects startified across the four zones described above. Starting in 2007, many new sites were added for monitoring MPAs established by the MLPA along the coast of central California. These MLPA sites are equivalent of one "side" of the orignal PISCO sites (i.e. 12 transects).

本元数据记录针对PISCO潮下带群落调查的鱼类调查工作进行说明。鱼类采样通过在样带（transect）上记录所有非隐蔽性鱼类的数量与体型完成。在每个采样点位，需对底栖样带、中层水体样带和冠层样带开展调查。所有样带的规格均为2米×2米×30米。
潮下带群落结构调查于每年夏季或初秋在全部调查点位开展，调查内容涵盖底质类型与地形起伏度、底栖覆盖度、大型藻类及无脊椎动物主要类群的丰度，以及鱼类的丰度与体型。采样的空间布设方案旨在量化群落结构在点位尺度上的年际变化，以及此类变化发生的空间尺度。
调查点位被定义为一段固定的海岸线，长度约为500米。最初，每个调查点位被划分为2个半区（侧区），每个半区包含12条按前述四个分区进行分层布设的样带。自2007年起，为监测加利福尼亚州中部沿海由MLPA设立的海洋保护区（Marine Protected Area，MPA），新增了大量调查点位。此类MLPA调查点位与原始PISCO点位的单个半区规模相当，即包含12条样带。