Density estimates of Spotted Handfish (Brachionichthys hirsutus) - GPS Underwater Visual Census. 2015-2016

Dive surveys were conducted in 2015 and 2016 to establish a baseline and monitor the status of the critically endangered spotted handfish (Brachionichthys hirsutus) population. This dataset contains track records of variable length, GPS tracked underwater visual census transects conducted within 11 sites across the Derwent Estuary (n=9) and D'Entrecasteaux Channel (n=2).

Records illustrated search effort (transect length, swathed area) and total fish sighted along each transect. Data were also presented in a standardised unit, with density estimates (fish per hectare [Ha]) extrapolated for each transect. In addition, this dataset also included information for each sighting of individual fish. This dataset contains size measurement (total length) and location (depth, latitude, longitude) records for each sighted fish.

本研究于2015年与2016年开展潜水调查，旨在建立基线数据并监测极危物种斑点手鱼（Brachionichthys hirsutus）的种群现状。
本数据集包含多条长度不等的轨迹记录，对应德文特河河口（n=9）与德恩特卡斯托海峡（n=2）共计11个调查点位内的GPS追踪式水下视觉普查样带数据。
每条记录涵盖了调查作业量（样带长度、扫查面积）以及每条样带沿途目击的总鱼类数量。
数据同时采用标准化单位进行呈现，并为每条样带推算得到种群密度估算值（单位：尾/公顷[Ha]）。
此外，本数据集还收录了每一次目击个体的相关信息。
具体包括每条目击鱼类的体长测量值（总长度）及其所处位置数据（水深、纬度与经度）。