Natural changes in pelagic fish stocks of the North Sea in the 1980s
Corten, A.; van de Kamp, G. (1992). Natural changes in pelagic fish stocks of the North Sea in the 1980s. ICES Mar. Sci. Symp. 195: 402-417
In: ICES Marine Science Symposia. ICES/Reitzel: Copenhagen. ISSN 0906-060X, more
|
| Keywords |
Distribution
Fisheries > Marine fisheries > Pelagic fisheries
Motion > Water motion > Water currents > Ocean currents
Population characteristics
Statistics > Fishery statistics > Catch statistics > Fish catch statistics
Stock assessment
Clupea harengus Linnaeus, 1758 [WoRMS]; Scomber scombrus Linnaeus, 1758 [WoRMS]
Marine/Coastal |
| Authors | | Top |
- Corten, A.
- van de Kamp, G.
|
|
|
| Abstract |
One of the conspicuous natural changes in North Sea fish stocks in the 1980s was a shift in summer distribution of the adult herring (Clupea harengus). During the 1970s and earlier decades, the main feeding grounds in June/July were the waters off the east coast of Scotland south of 57° N and west of 2° E. During the 1980s, very few herring were found in this area during the feeding season. The distribution of the adult had shifted north and northeast, to the edge of the continental shelf and to the Norwegian Trench. Herring recruitment steadily increased during the early 1980s, and was above the long-term average from 1984 to 1986. During the years of strong recruitment, a relatively high proportion of North Sea juveniles grew up in the Skagerrak/Kattegat. The change in adult herring distribution corresponded in time and area with earlier documented changes in western mackerel (Scomber scombrus). In both species, the summer distribution shifted towards the northeastern North Sea. The changes in both species occurred at the edge of the continental shelf, in the region of the shelf edge current. It is therefore suggested that changes in the shelf edge current might have been responsible for the observed changes. |
|
