Pacific herring
| Pacific herring | ||||||||||||
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Pacific herring ( Clupea pallasii ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Clupea pallasii | ||||||||||||
| Valenciennes , 1847 |
The Pacific herring ( Clupea pallasii ) has long been considered a form or subspecies of the Atlantic herring ( Clupea harengus ), but for about 25 years it has been increasingly viewed as a separate species, named after Peter Simon Pallas . The differences are fluid (it usually has 52–55 eddies versus 55–57, for example), but the populations are divided - they are only sympatric in the north-eastern European Arctic Ocean ( White Sea ). Despite the biological similarity, the history of human use has been very different.
distribution
The Pacific herring occurs between Korea ( Yellow Sea ), Northern Japan (N- Honshū , Hokkaidō ), the Bering Strait, the Aleutian Islands and California (or N-Mexico) in coastal areas (deepest catches allegedly from 475 m). Isolated populations exist on the north coast of Canada and (as mentioned) between the Murman coast and the Ob estuary. The swarms sometimes penetrate river estuaries, and there are apparently even freshwater populations cut off from the sea (some lakes on Sakhalin , Hokkaidō, Honshū).
features
The fish is (proven) 46 cm long (usually about 35 cm) and 19 years old. It is sexually mature at three to nine years old, depending on the growing conditions.
Way of life
Due to the low tendency to migrate, a number of "local races" could emerge: In contrast to the Atlantic herring, it does not form large migrations, but only changes to shallower zones (near the shore) during spawning. In cold seas there is usually a lower salinity (rain, rivers), and it is precisely this that is beneficial for egg and larval development (see also Totoaba and other Sciaenidae ). The spawning season coincides with the season of high plankton production: from February (NW Pacific) to October ( San Diego region), usually at temperatures of 3–9 ° C.
Fishing
In contrast to the Atlantic herring, which has been popular throughout Europe for centuries, the Pacific herring is only of local importance as a food fish , e.g. B. in Korea . Nevertheless, at the end of the 20th century, the catch fell sharply, so that protective regulations had to be issued. The main reason for this was that eggs (the “roe”) are a popular delicacy in Japan , which was also sought after on the North American west coast (after an import ban was lifted around 1972). In important spawning areas, large areas of seaweed mats ( Macrocystis pyrifera, etc.) were introduced and then salted in with the spawning deposited on them and shipped. Or the Rogner were sent to East Asia as " caviar containers", so to speak - the stripped bodies of the females and the males ("milkers") were then mostly used for the production of fish meal and fish oil or as fertilizer . In 1964 almost 800,000 tons were caught, but since the 1980s much less, B. 1999 almost 472,000 tons. Protection programs should now secure the stocks, which can also be endangered locally by sewage and biotope destruction (some stocks have not yet recovered). For comparison: three to four times more of the Atlantic species are caught.
swell
- Clupea pallasii , species portrait at the Food and Agriculture Organization of the United Nations (FAO)
- Habitat Assessment: Pacific Herring and Oil , Alaska Fisheries Science Center (protection of threatened populations off Alaska who were exposed to oil pollution, among other things)
- Pacific herring on Fishbase.org (English)