We analyzed spatial distributions of 10 euphausiid species in the southern California Current System across seven El Niño events (1951–2018) and the 2014–15 Warm Anomaly to determine variations in habitat utilization and reproduction during Eastern Pacific (EP) and Central Pacific (CP) Niños. Our goal was to characterize the main forcing mechanisms by which El Niño events influence these dominant species. Our findings suggest cool-water euphausiids respond predominantly to changing in situ habitat conditions during El Niño, while subtropical species require initial advection to increase in the southern CCS. Cool-water coastally-associated species (Euphausia pacifica, Thysanoessa spinifera) compress shoreward and retract poleward to upwelling waters during EP Niños, likely in response to offshore warming. A subtropical coastal species (Nyctiphanes simplex) extends poleward nearshore during EP Niños, suggesting anomalous advection, but increases only moderately and variably off southern California during CP Niños. A Tropical Pacific-Baja California species (Euphausia eximia) only appears off southern California in spring during El Niño years (EP, some CP), suggesting direct advection and low tolerance for cooler, fresher conditions. Subtropical offshore species (Euphausia gibboides, Euphausia recurva, Stylocheiron affine, Euphausia hemigibba) expand shoreward during most Niños (strongest during 2014–15 Warm Anomaly) and show moderate in situ post-event persistence, suggesting combined influence of advection and temporarily favorable habitat nearshore. Regionwide temperate species (Nematoscelis difficilis, Thysanoessa gregaria) contract only moderately shoreward during some Niños. Predictions of Year 2100 distributions using generalized additive models suggest future non-Niño conditions and CP Niños will produce regionwide in situ increases in subtropical species and moderate poleward and onshore expansions, while EP Niños will produce continued nearshore habitat compression and reduced abundance of coastal species. Understanding zooplankton spatial responses to El Niño can help predict community compositional shifts under other ocean changes (e.g., long-term trends, basin-wide warm anomalies).

我们分析了南加州当前系统中的10个金黄色葡萄球菌物种在7个厄尔尼诺事件（1951-2018）和2014-15暖异常中的空间分布，以确定东太平洋（EP）和中太平洋（CP）的栖息地利用和繁殖变化）尼诺斯。我们的目标是表征厄尔尼诺事件影响这些优势物种的主要强迫机制。我们的发现表明，在厄尔尼诺期间，冷水沼虾主要对原地栖息地条件的变化做出反应，而亚热带物种则需要初步平流以增加CCS南部的面积。沿海与冷水有关的物种（Euphausia pacifica，Thysanoessa spinifera）在EPNiños期间向岸压缩并向极点撤回，这可能是由于近海变暖所致。亚热带沿海物种（Nyctiphanes simplex）在EPNiños期间向近海极地延伸，表明对流异常，但在CPNiños期间仅在南加利福尼亚以外地区适度增加。热带太平洋-下加利福尼亚州的一个物种（Euphausia eximia）仅在厄尔尼诺年（EP，某些CP）的春季出现在加利福尼亚南部附近，表明直接对流并且对较冷，较新鲜条件的耐受性较低。亚热带近海物种（Euphausia gibboides，Euphausia recurva，Stylocheiron affine，Euphausia hemigibba）在大多数尼诺斯岛（2014-15暖异常期间最强）向岸扩张，并显示适度原位后事件的持久性，这表明相结合平流影响，暂时有利的栖息地近岸。整个区域的温带物种（Nematoscelis difficilis，Thysanoessa gregaria）在某些尼诺斯时期仅适度向岸收缩。使用广义加性模型对2100年分布的预测表明，未来的非尼诺河条件和CPNiños将导致亚热带物种在全区域范围内就地增加以及适度的极地和陆上扩张，而EPNiños将产生持续的近岸生境压缩并减少沿海物种的丰度。了解厄尔尼诺现象对浮游动物的空间响应，可以帮助预测其他海洋变化（例如长期趋势，全流域暖异常）下的群落组成变化。