Polar cod (Boreogadus saida) is a key forage fish in the Arctic marine ecosystem and provides an energetic link between lower and upper trophic levels. Despite its ecological importance, spatially explicit studies synthesizing polar cod distributions across research efforts have not previously been conducted in its Pacific range. We used spatial generalized additive models to map the distribution of polar cod by size class and relative to environmental variables. We compiled demersal trawl data from 21 cruises conducted during 2004–2017 in the Chukchi and Beaufort seas, and investigated size-specific patterns in distribution to infer movement ecology of polar cod as it develops from juvenile to adult life stages. High abundances of juvenile polar cod (≤ 70 mm) in the northeastern Chukchi Sea and western Beaufort Sea were separated from another region of high abundance in the eastern Beaufort Sea, near the US and Canadian border, suggesting possible population structure in the Pacific Arctic. Relating environmental correlates to polar cod abundance demonstrated that temperature and salinity were related to juvenile distribution patterns, while depth was the primary correlate of adult distribution. A comparison of seasonal 2017 abundances of polar cod in the southern Chukchi Sea found low demersal abundance in the spring when compared to the summer. Seasonal differences in polar cod abundance suggest that polar cod migration may follow a classical ‘migration triangle’ route between nursery grounds as juveniles, feeding grounds as subadults, and spawning grounds as adults, in relation to ice cover and seasonal production in the Chukchi Sea.

中文翻译：

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楚科奇海和波弗特海极地鳕鱼（Boreogadus Saida）分布的空间模式、环境相关性和潜在的季节性迁移三角形

极地鳕鱼 (Boreogadus saida) 是北极海洋生态系统中的一种重要饲料鱼，在低营养级和高营养级之间提供了能量联系。尽管具有生态重要性，但此前尚未在其太平洋范围内进行跨研究工作综合极地鳕鱼分布的空间明确研究。我们使用空间广义加性模型按大小类别和相对于环境变量来绘制极地鳕鱼的分布图。我们汇编了 2004 年至 2017 年在楚科奇海和波弗特海进行的 21 次航行的底层拖网数据，并调查了特定大小的分布模式，以推断极地鳕鱼从幼年到成年生活阶段的运动生态。楚科奇海东北部和波弗特海西部的高丰度幼年极地鳕鱼（≤ 70 毫米）与波弗特海东部靠近美国和加拿大边境的另一个高丰度地区分开，这表明太平洋北极可能存在种群结构。环境与极地鳕鱼丰度的相关性表明，温度和盐度与幼鱼分布模式有关，而深度是成鱼分布的主要相关因素。对楚科奇海南部 2017 年季节性极地鳕鱼丰度的比较发现，与夏季相比，春季底层丰度较低。极地鳕鱼丰度的季节性差异表明，极地鳕鱼的迁徙可能遵循经典的“迁徙三角”路线，在幼鱼的育苗场、亚成鱼的觅食地、