Otolith annual growth increments for cod populations in the Northeast Atlantic

Large-scale, climate-induced synchrony in the productivity of fish populations is becoming more pronounced in the world’s oceans. As synchrony increases, a population’s ‘portfolio’ of responses can be diminished, in turn reducing its resilience to strong perturbation. Here we argue that the costs and benefits of trait synchronization, such as the expression of growth rate are context dependent. Synchrony among individuals could actually be beneficial for populations if growth is optimized during favourable conditions and then declines under poor conditions when a broader portfolio of responses is needed. Importantly, growth synchrony among individuals within populations has seldom been measured, despite well-documented evidence of synchrony across populations. Here, we used century-scale time series of annual otolith growth to test for changes in growth synchronization among individuals within multiple populations of a marine keystone species (Atlantic cod, Gadus morhua). On the basis o...全球海洋中，由气候驱动的鱼类种群生产力大规模同步现象正日益显著。随着同步性提升，种群的响应组合会被削弱，进而降低其应对强扰动的恢复力。本研究认为，性状同步（如生长速率的表达）的利弊取决于具体情境。若种群在适宜条件下生长最优，而在需要更广泛响应组合的恶劣条件下生长速率下降，那么个体间的同步性实际上可能对种群有益。值得注意的是，尽管已有充分证据证明种群间的同步现象，但种群内部个体间的生长同步性却极少被研究。本研究依托百年尺度的年度耳石（otolith）生长时间序列，对一种海洋关键物种——大西洋鳕（Gadus morhua）的多个种群内部个体间的生长同步性变化进行了检测。基于……