Interactions between biology, environmental and anthropogenic factors on the exploitation of pelagic species by the Scottish fleet

鲱鱼和鲭鱼是洄游鱼种，在产卵和/或觅食集群期间是季节性目标。这些鱼种占苏格兰中上层渔业的80%（按重量计），占整个苏格兰渔业部门的55%（按重量计）和40%（按价值计）。苏格兰船队是21艘大型（>40- 85米）现代拖网渔船，位于设得兰群岛、彼得黑德和弗拉瑟堡。捕捞效率，加上限制配额和物种的洄游行为，导致相对较短的季节性渔业，主要是：鲱鱼7月至8月和鲭鱼1月/2月和10月/11月。作为其中的一部分，自2018年以来，该行业通过SPFA与UHI和MSS合作，制定了渔民自我采样和渔民/科学联合采样计划，这些计划已被苏格兰政府采用作为收集浮游生物数据的途径。这些方案收集关于逐批分辨率的数据，并提供关于以前无法获得的分辨率的生物数据。数据集继续增长，已经成熟，可以分析生物因素和与环境变量的相互关系。除了渔获量数据中明显的季节性和年际变化外，还有一系列外部因素影响船长在何时捕鱼、他们在鱼的大小、成熟度和状况方面的目标以及在哪里卸货（苏格兰加工商或国外）等方面作出的捕鱼选择。这些受市场力量影响，近年来受到俄罗斯制裁（自2019年以来）和2022年乌克兰战争的重大影响。从1945年到2000年，中上层渔业的发展已有文献记载[2]，但自2000年以来，船队全面更新，技术进步显著，提高了捕捞效率。此外，通过AIS和VMS引入船舶可见度，使船长能够跟踪船队所在位置，消除了捕鱼地点的秘密-文化的巨大变化，减少了船舶搜索浅滩的时间，改变了渔民的行为将进一步提高捕捞效率，并可能通过燃料消耗减少碳足迹。学生将与学术界和远洋产业合作。这项研究将包括跨学科数据收集的一个要素，通过社会科学方法收集和分析渔民的知识，同时分析经验数据集。

Herring and mackerel are migratory species and targeted seasonally during spawning and/or feeding aggregations. These species comprise 80% by weight of the Scottish pelagic fisheries, and account for >55% by weight, and >40% by value of the entire Scottish fishing sector. The Scottish fleet is 21 large (>40-85m) modern trawlers based in Shetland, Peterhead and Fraserburgh. The fishing efficiency, combined with both restricted quotas and the migratory behaviour of the species result in relatively short seasonal fisheries that are mainly: herring July-Aug and mackerel Jan/Feb and Oct/Nov. Large fluctuations in annual fishing quota together with a mis-match between fisher observations and assessment output led to industry calls for improved science on these stocks. As part of this, the industry through the SPFA, have worked in partnership with UHI and MSS since 2018 to develop fisher self-sampling and fisher/science co-sampling programmes that have been adopted as the route through which the Scottish Government collects pelagic data [1]. These programmes collect data on a haul-by-haul resolution and are providing biological data on previously unobtainable resolution. The data-set continues to grow and is ripe for the analysis of biological factors and for correlation to environmental variables. In addition to immediately apparent seasonal and inter-annual variations within the catch data, there are a range of external factors that affect the fishing choices that skippers make in relation to when to fish, what they are targeting regarding fish size, maturity and condition, and where to land their catches (Scottish processors or abroad). These are influenced by market forces and have in recent years been significantly affected by Russian sanctions (since 2019) and in 2022 by the Ukraine war. The development of the pelagic fisheries from 1945 until 2000 has been documented [2] but since 2000 there has been a complete fleet renewal and significant technological advances that have improved fishing efficiency. Additionally, the introduction of vessel visibility through AIS and VMS has resulted in skippers being able to track where the fleet are, has eliminated fishing location secrecy - a huge change in culture, has cut the amount of time vessels spend searching for shoals and the altered fisher behaviour will have further increased catching efficiency and may have reduced carbon footprint through fuel consumption. The student will work collaboratively with both academia and the pelagic industry. The research will include an element of cross-disciplinary data collection from the incorporation of the collection and analysis of fisher knowledge, through social science-based methodologies, alongside the analysis of empirical datasets.