Changes in the perception of the migration pattern of Northeast Atlantic mackerel during the last 100 years

The perception of mackerel migration has changed over time from the old hypothesis that mackerel undertook relatively short migrations from spawning grounds off the coast to deeper waters nearby where they hibernated during the winter, to the present recognition of mackerel as a highly migratory species. The stock size and migration pattern of the different spawning components/stocks of mackerel in the Northeast Atlantic have changed over time and, as a consequence, the fishery and its management as well. Changes in the migration pattern of Western mackerel were observed, particularly when the North Sea mackerel collapsed in the late 1960s. They migrated more extensively into the Norwegian Sea and North Sea, probably in effect replacing the depleted North Sea mackerel. A tagging experiment in 1994 demonstrated that Southern mackerel mixed with and followed the same migration route as the Western mackerel.