The Limfjord herring fishery is anomalous due to the unique nature of the changing topography that has forged uniquely inland sea waters in the Jutland Peninsula. Until a breach at Agger Tange in 1825, affording access to the North Sea, the only access was to the east via the Kattegat. The breach enabled salt water to penetrate the Limfjord which had previously been brackish. It may be argued that despite the obvious, radical changes to the salinity, hydrography and nutrient levels that the breach caused, herring fishing was impacted prior to this event by a combination of fishing methods and the destruction of spawning grounds.
Funding
European Research Council Advanced Grant (2016-2020), NorFish, ERC-2014-ADG