CE20013 Celtic Explorer Irish Groundfish Survey 2020 Legs 1-3 North East Atlantic Ocean

This survey was conducted on board the RV Celtic Explorer in 2020 by the Marine Institute (MI) as part of the annual groundfish survey to determine the distribution and abundance of commercial fish around Ireland. The Irish Groundfish Survey (IGFS) forms part of the International Bottom Trawl Survey (IBTS) programme, an international survey effort coordinated by the International Council of the Exploration of the Sea (ICES). Each year the survey, taking place in Autumn/Winter, collects demersal trawl and ancillary data in Irish waters to produce relative abundance indices for fisheries management. In particular the survey provides an index of the share of young fish in the stock, which in turn gives an indication of its spawning success. The IGFS contributes to Ireland's international obligation to supply scientific data that support the implementation of the Common Fisheries Policy (CFP). This survey is a series of demersal sampling trawls at pre-defined stations. The 2020 survey took place over 3 legs. Not all stations were surveyed due to weather downtime or no CTDs were carried out. The primary goal of the Irish Groundfish Survey is to develop estimates of juvenile abundances for important commercial fish species. Measurements of the abundance of juvenile fish are a critical measure of the health of a stock, serving as an annual indication of recruitment (the number of newly spawned fish which enter the population each year) success or failure. Most importantly, they allow forecasting of future commercial abundance. In addition, the Irish Groundfish Survey provides data on the distribution and biology of commercial and non-commercial species of ecological interest, as well as hydrographic and environmental observations.本调查于2020年由爱尔兰海洋研究所（Marine Institute, MI）在“凯尔特探险家号”（RV Celtic Explorer）研究船上开展，作为年度底栖鱼类调查的一部分，旨在探明爱尔兰周边海域商业鱼类的分布与资源丰度。爱尔兰底栖鱼类调查（Irish Groundfish Survey, IGFS）是国际底拖网调查（International Bottom Trawl Survey, IBTS）计划的组成部分，该计划是由国际海洋考察理事会（International Council for the Exploration of the Sea, ICES）协调推进的国际性调查工作。该调查于每年秋冬两季开展，在爱尔兰海域采集底拖网采样及配套辅助数据，以生成渔业管理所需的相对资源丰度指数。尤为关键的是，本调查可生成种群中幼鱼占比的相关指数，进而反映该种群的产卵繁育成效。爱尔兰底栖鱼类调查有助于爱尔兰履行其国际义务，为支持《共同渔业政策》（Common Fisheries Policy, CFP）的实施提供科学数据支撑。本次调查通过在预设站位开展底拖网采样的方式进行。2020年本次调查共分为3个航次开展，但受天气延误影响，或因未开展温盐深（CTD）测量，部分预设站位未能完成调查采样。爱尔兰底栖鱼类调查的核心目标是对重点商业鱼类的幼鱼资源丰度进行估算。幼鱼资源丰度的测量数据是评估种群健康状况的关键指标，可作为年度补充量（即每年新孵化并加入种群的幼鱼数量）成败的直观体现。更为重要的是，此类数据可用于预测鱼类种群未来的商业资源丰度。此外，爱尔兰底栖鱼类调查还可采集具有生态价值的商业及非商业物种的分布与生物学数据，同时开展水文与环境观测工作。