Reported annual fishing effort from Commonwealth fisheries logbooks

##Description\r\nWhile at sea, Commonwealth fishers must record all catch and effort in their AFMA daily fishing logbooks. This dataset shows the annual fishing effort by fishery and gear, that fishers have recorded in their logbooks for Commonwealth fisheries managed by the Australian Fisheries Management Authority (AFMA). Location of effort within a fishery is not included.\r\nThese data are sourced from AFMA daily fishing logbooks, which fishers complete while at sea. Location of effort within a fishery is not included.\r\nFishing effort is measured differently depending on the fishing method used. In this dataset we provide the most common measures that are used by scientists. \r\n\r\n##Appropriate use and limitations of the data\r\nThe effort data in logbooks are estimates only, which have been recorded by fishers while at sea. Effort data are used in combination with catch data, spatial data, and other relevant information (such as independent surveys) to inform stock assessments.\r\nThese data may differ from other summations over the same time-period (such as stock assessment reports) due to differences in data handling procedures. For example, scientists may standardise effort for assessments to account for issues such as changes in gear efficiency, catchability of fish and skipper expertise. They may also filter out effort from their assessments because of data quality issues.\r\nCare should be taken when interpreting trends in this data because there are many factors that can affect effort each year. Catch quantities can be impacted by management measures such as closures of fishing areas or reducing boat numbers. Similarly, changes in market demand can change fishing decisions and affect effort. \r\n\r\n##Disclaimer\r\nThe dataset provided by AFMA is comprised of raw (unprocessed) data as received from fishers, and may contain errors or be incomplete. AFMA makes no warranty or representation that the data is accurate or complete. Those who choose to use this data should make their own enquiries as to its accuracy and completeness and AFMA assumes no liability for any errors or omissions in the data provided, or for any decision by a person who chooses to rely on the data.\r\n

## 数据集说明
海上作业期间，英联邦辖区渔民须将所有渔获与捕捞努力量填报至澳大利亚渔业管理局（Australian Fisheries Management Authority, AFMA）每日捕捞日志簿中。本数据集收录了由AFMA管理的英联邦辖区渔业中，渔民在日志簿内记录的按渔业类型与渔具划分的年度捕捞努力量数据，渔业内部的作业点位信息未纳入本数据集。

本数据集数据源自渔民海上作业时填写的AFMA每日捕捞日志簿，渔业内部的作业点位信息未纳入其中。

捕捞努力量的统计方式因捕捞作业方式而异，本数据集采用科研人员通用的主流统计标准进行数据呈现。

## 数据合理使用与局限性
日志簿记录的捕捞努力量数据仅为估算值，由渔民在海上作业时填报。捕捞努力量数据需与渔获数据、空间数据及其他相关信息（如独立调查数据）结合使用，以支撑渔业资源评估工作。

由于数据处理流程存在差异，本数据集与同期其他汇总数据（如渔业资源评估报告）可能存在出入。例如，科研人员为开展资源评估，可能会针对渔具效率变化、鱼类可捕性变化以及船长作业经验差异等因素对捕捞努力量进行标准化处理；也可能因数据质量问题，在评估中剔除部分作业量数据。

解读本数据集的年度变化趋势时需谨慎，因为每年的捕捞努力量受多种因素影响。渔获量可能受渔业管理措施影响，例如禁渔区划定或渔船数量缩减；同理，市场需求变化也会改变捕捞决策，进而影响作业努力量。

## 免责声明
AFMA提供的本数据集为直接从渔民处获取的原始（未加工）数据，可能存在错误或不完整之处。AFMA不对数据的准确性与完整性作出任何保证或声明。使用本数据集的主体应自行核实数据的准确性与完整性，AFMA不对所提供数据中的任何错误、遗漏，或因依赖该数据作出决策而产生的任何后果承担责任。