Understanding patterns of change in the distribution of species among their critical habitats is important for analyzing population dynamics and adaptive responses to environmental shifts. We investigated spatio-temporal changes in small yellow croaker (Larimichthys polyactis) using eight alternative models fitted to data from bottom trawl surveys conducted in the Bohai Sea each spring (spawning period) and summer during 1982–2018. These models included different combinations of local sea temperature, fishing pressure, and individual climate index (i.e., North Pacific index, NPI, and West Pacific index, WPI) as explanatory variables. Selection of the most parsimonious model for each season was based on Akaike’s Information Criterion (AIC). The model with NPI as its only explanatory variable was used as a base case for pre-analysis. In spring, a spatio-temporal model with sea temperature as a quadratic effect, plus the spatially varying effects of a climate index and fishing pressure was selected, as the AIC value of this model was reduced by 41.491 compared to the base case model without these effects. In the summer after spawning, the spatio-temporal model with WPI as a climate index covariate lagged by 1-year best explained the spatio-temporal distribution patterns of the stock. The results suggested that small yellow croaker populations significantly decreased in biomass in the Bohai Sea over the study period. A statistically significant northeastward shift in the center of gravity (COG) and a contraction in the distribution range occurred in summer throughout the study period (p<0.05). During the spring sequence (1993–2018), a statistically significant northeastward shift in the COG was also found (p<0.05). Our results showed that biomass-density hotspots of small yellow croaker in both seasons have shrunk or disappeared in recent years. Overall, these findings suggest that the spatio-temporal patterns of the populations in their spawning, feeding and nursery grounds have been influenced over the past 40 years by multiple pressures, and population density in the southwestern areas of the Bohai Sea declined faster and more drastically than in the northeastern areas. This study has important implications for developing targeted spatial conservation measures for small yellow croaker at various stages of its life history under different levels of stress.

了解物种在其关键栖息地中分布的变化模式对于分析种群动态和对环境变化的适应性反应非常重要。我们调查了小黄鱼的时空变化（鲈鱼) 使用八种替代模型拟合 1982-2018 年间每年春季（产卵期）和夏季在渤海进行的底拖网调查数据。这些模型包括当地海水温度、捕捞压力和个别气候指数（即北太平洋指数，NPI 和西太平洋指数，WPI）的不同组合作为解释变量。每个季节最简约的模型的选择是基于 Akaike 的信息标准 (AIC)。以 NPI 作为唯一解释变量的模型被用作预分析的基础案例。在春季，选择了以海温作为二次效应的时空模型，加上气候指数和捕捞压力的空间变化效应，因为与没有这些的基本案例模型相比，该模型的 AIC 值降低了 41.491效果。在产卵后的夏季，以WPI为气候指数协变量滞后1年的时空模型最能解释种群的时空分布格局。结果表明，研究期间渤海小黄鱼种群的生物量显着减少。在整个研究期间的夏季，重心 (COG) 向东北方向发生了统计上显着的偏移，分布范围缩小（p<0.05)。在春季序列（1993-2018 年）期间，还发现 COG 发生了统计学上显着的东北偏移（p<0.05)。我们的研究结果表明，近年来小黄鱼在两个季节的生物量密度热点都在缩小或消失。总体而言，这些研究结果表明，过去 40 年来，种群在产卵、觅食和育苗场的时空格局受到多重压力的影响，渤海西南地区的种群密度下降得更快、更剧烈。高于东北地区。本研究对针对不同应激水平下生活史不同阶段的小黄鱼制定有针对性的空间保护措施具有重要意义。