| Synchrony in population fluctuations have commonly been observed among a variety of species. They are generally attributed to the effect of common environmental forcings on population dynamics. Here, we investigate long term synchrony in the recruitment variations of the North East Atlantic fish populations. A PCA (principal component analysis) was performed to extract the main patterns of variation. The most significant one reflects the synchronous decrease of the recruitment for the majority of gadoids populations, in the Baltic Sea, Kattegat, North Sea, Irish Sea and West of Scotland. The inverse pattern was observed for half of the herring populations. Plaice populations also exhibit synchronous recruitment trends, characterised by strong year classes... |
