Northern Pelagic Shark Tagging Data 1983-1985 (releases), 1983-1997 (recaptures)

Between February 1983 and May 1985, some 10 500 sharks of 23 species were fin-tagged off northern Australia. Tagging concentrated on the commercially important Carcharhinus tilstoni and C. sorrah. Most recaptures were made in 1984 and 1985, but returns continued until May 1997. In all 579 tags (5.5%) were recovered. Tag shedding was estimated to be low (0.025 year1 for C. tilstoni) and tagging mortality was significantly lower for sharks caught by handline than by gillnet. Australian gillnetters, Taiwanese gillnetters (fishing in the Australian Fishing Zone) and Australian prawn trawlers accounted for most of the returns. The maximum distance between the release and recapture positions was over 1100 km, but most returns were made within 50 km of the tagging site. Nearly all of the releases were in inshore waters fished by Australian vessels. Although substantial numbers of recaptures were made by the offshore Taiwanese fishery, when fishing effort was considered, relatively few sharks appeared to move from inshore to offshore waters. This dataset contains the release and recapture information for all tag events and was collected as part of the CSIRO Northern Pelagic Fish Stock Research Project.

1983年2月至1985年5月期间，研究人员在澳大利亚北部海域为23个物种的约10500条鲨鱼安装了鳍标（fin tag）。本次标记工作重点针对具有商业开发价值的蒂氏真鲨（Carcharhinus tilstoni）与直齿真鲨（C. sorrah）。绝大多数重捕事件发生于1984年和1985年，但标记回收工作持续至1997年5月。累计回收标记579个，回收率达5.5%。经估算，标记脱落率较低，其中蒂氏真鲨的年脱落率为0.025；手钓捕获的鲨鱼的标记死亡率显著低于刺网捕获个体。澳大利亚刺网渔船、在澳大利亚捕捞区内作业的中国台湾刺网渔船以及澳大利亚对虾拖网渔船贡献了绝大多数回收标记。放流位点与重捕位点间的最大直线距离超过1100公里，但绝大多数重捕个体均在距标记位点50公里以内的海域被捕获。几乎所有放流操作均开展于澳大利亚渔船作业的近岸海域。尽管近海台湾捕捞船队完成了相当数量的重捕操作，但结合捕捞努力量进行分析后可见，从近岸向远海移动的鲨鱼数量相对较少。本数据集涵盖所有标记事件的放流与重捕信息，其采集工作是澳大利亚联邦科学与工业研究组织（Commonwealth Scientific and Industrial Research Organisation, CSIRO）北部中上层鱼类种群研究项目的组成部分。