A multivariate approach was used to analyze spring zooplankton abundance in Shelikof Strait, western Gulf of Alaska. abundance of individual zooplankton taxa was related to environmental variables using generalized additive models. The most important variables that correlated with zooplankton abundance were water temperature, salinity and ordinal day (day of year when sample was collected). A long-term increase in abundance was found for the calanoid copepod Calanus pacificus, copepodite stage 5 (C5). A dynamic factor analysis (DFA) indicated one underlying trend in the multivariate environmental data that related to phases of the Pacific Decadal Oscillation. DFA of zooplankton time series also indicated one underlying trend where the positive phase was characterized by increases in the abundance of C. marshallae C5, C. pacificus C5, Eucalanus bungii C4, Pseudocalanus spp. C5 and Limacina helicina and declines in the abundance of Neocalanus cristatus C4 and Neocalanus spp. C4. The environmental and zooplankton DFA trends were not correlated over the length of the entire time period; however, the two time series were correlated post-2004. The strong relationship between environmental conditions, zooplankton abundance and time of sampling suggests that continued warming in the region may lead to changes in zooplankton community composition and timing of life history events during spring.

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1990年至2017年，美国阿拉斯加西部谢里科夫海峡浮游动物的丰度趋势和格局

多变量方法用于分析阿拉斯加西部谢里科夫海峡春季浮游动物的数量。使用广义加性模型，单个浮游生物类群的丰度与环境变量相关。与浮游动物的丰度相关的最重要的变量是水温，盐度和序数日（一年中采集样品的日期）。发现the足类co足类动物Calanus pacificus，co足类动物第5阶段（C5）的长期丰度增加。动态因素分析（DFA）显示了与太平洋年代际振荡各阶段有关的多元环境数据的一种潜在趋势。浮游动物时间序列的DFA还表明了一种潜在趋势，其中正相的特征是鱼的丰度增加C. marshallae C5，C. pacificus C5，Eucalanus天牛C4，Pseudocalanus属。C5和螺旋藻（Limacina helicina），以及新cal（Neocalanus cristatus） C4和新cal（Neocalanus spp）的丰度下降。C4。在整个时间段内，环境和浮游动物的DFA趋势均不相关；但是，这两个时间序列在2004年之后是相关的。环境条件，浮游动物丰度与采样时间之间的密切关系表明，该地区持续变暖可能导致浮游动物群落组成的变化以及春季生活史事件的发生时间。