Zooplankton predator–prey relations in northern Norwegian fjords are highly variable in time and space, and the mechanisms driving this variability are still poorly understood. Replicate Juday net sampling in October and February from 1983 to 2005, which included five repeated tows from bottom to surface, was conducted in Saltfjord and Mistfjord, northern Norway. The time-series provided evidence of in situ variability in species abundance, as well as seasonal and interannual changes in standing stock abundance. The shallow sill of one fjord caused accumulation of coastal water in the fjord’s basin, while the other fjord’s deeper sill selected denser water of Atlantic origin from the same open shelf habitat. The selective advection caused differences in the immigration of species recruiting to the fjords’ specific overwintering communities of zooplankton. Statistical analyses of the cumulated replicate data indicated significant in situ variability in the spatial density of species. Cases with an abundance of carnivores relating positively to other species probably resulted from the carnivores’ attraction to patches with concentrations of prey. Interspecific negative density relations likely indicated either predator avoidance or substantial trophic activity during the sampling. During years of high abundance, some wintering stocks of carnivores evidently reduced the local stocks of overwintering prey. We conclude that predator–prey interactions and stock variability in Subarctic fjords result from complex bio-geophysical interactions that occur on the scales of local habitats and basin-scale population systems.

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亚北极峡湾浮游动物越冬的可变捕食者-猎物关系

挪威北部峡湾的浮游动物捕食者-猎物关系在时间和空间上变化很大，驱动这种变化的机制仍然知之甚少。1983 年至 2005 年 10 月和 2 月的重复 Juday 净采样，包括从底部到表面的 5 次重复拖曳，在挪威北部的 Saltfjord 和 Mistfjord 进行。时间序列提供了物种丰度的就地变异性以及常备种群丰度的季节性和年际变化的证据。一个峡湾的浅基台导致了该峡湾盆地沿海水的积累，而另一个峡湾较深的基台选择了来自同一开放大陆架栖息地的大西洋来源的密度更大的水。选择性平流导致招募到峡湾特定浮游动物越冬群落的物种的迁移存在差异。累积重复数据的统计分析表明物种空间密度的原位变异性显着。大量食肉动物与其他物种呈正相关的情况可能是由于食肉动物被猎物集中的斑块所吸引。种间负密度关系可能表明在采样期间避免捕食者或大量的营养活动。在丰度高的年份，一些肉食动物的越冬种群明显减少了当地越冬猎物的种群。