Jungfischsituation in der Nordsee wenig ermutigend

In order to investigate the abundanceand strength of most recent year classes of cod,haddock, whiting, Norway pout, herring, sprat, and mackerel seven researchvessels of ICES member states carried out a bottom trawl survey in the North Sea in January/February 1996. Germany took part in these investigations by R.V. "Walther Herwig III" from January 19 to February 9 covering 62 out of 332 international stations. No substantial positive or negative results concerning the incoming year classes were obtained. As expected, the hydrographc situation of the area under investigation was strongly influenced by the actual weather: On the one hand, the continuous cooling of the surface layer by cold air caused vertical mixing down into the bottom layer in larger areas, and led to decreasing water temperatures which were below the long term values in nearly all the North Sea at the end of the investigation period. On the other hand, the continuous southern to eastern winds over the North Sea led to horizontal water mass transports renewing vertical salinity differences and inducing regionally positive as weH as negative salinity anomalies of up to 0.6· 10-3. ,

Die Herings-Polarstamm-Theorie 250 Jahre alt - und aktuelle Bezüge

250 years ago, in Hamburg a herring polar migration theory was published as part of the "Nachrichten von Island, Grönland und der Straße Davis" from the literary remains of the mayor Dr. Johann Anderson. Based on various sources and capable to answer to the herring questions of the time, this one-stock-migration theory became international hypothesis during the following tenth of years. It still is classified as remarkable because some actual ideas on herring migration were thought already 250 years ago. Abstract DE: In Hamburg wurde vor 250 Jahren eine Polarstamm-Theorie zur Heringswanderung als Teil der Nachrichten von Island, Grönland und der Strasse Davis aus dem Nachlass des Bürgermeisters Dr. Johann Anderson veröffentlicht. Aufbauend auf unterschiedliche Quellen und in der Lage, die damaligen Fragen um den Hering zu beantworten, wurde diese Ein-Stamm-Theorie zur heringswanderung über Jahrzehnte internationale Lehrmeinung. Sie wird auch heute noch als bemerkenswert eingestuft. Denn sie enthielt vor 250 Jahren schon Gedankengänge, die noch aktuell sind.

"Global Change" und das Meer als Nahrungsquelle

The potential importance of marine produetion as a protein ressource for a growing human population can hardly be overestimated. Climatic changes in the marine environment may affect marine production in a significant way. Increasing levels of UV-B may decrease primary production and thus diminish the food base for harvestable marine ressources. Direct effects on early stages of fishes may occur. Temperature changes can lead to additional mortality in the early phase of life histories of fishes. In spite of the potentially negative scenario, actual effects of global change on the ressources have not been detected so far. The marine organisms dispose of a significant level of pre-adaptation to changes of environmental factors both on a seasonal and an interannual scale. Effects on marine life may therefore be less dramatic than those on terrestrial systems, which are more directly linked with the exponentially growing human population.

Fisch als Wirtschaftsobjekt

Redemanuskript eines Vortrages vor dem Wirtschaftsausschuß für Außenhandelsfragen des Bundesministeriums für Ernährung, Landwirtschaft und Forsten am 26.4.95 in Bonn

Kräftiger Nachwuchs bei Schellfisch, Stintdorsch und Sprott

Seven research vessels of ICES member countries participated, in order to investigate the strength of incoming yearclasses of commereially most important species. Germany took part in the investigations by R.V. "Walther Herwig III" from January 23 to February 24. Indices of a total of 330 stations indicate a positive development of the stocks of haddock, Norway pout and sprat whereas indices for cod, whiting, and herring remain in the mean of the last years. Water temperatures were up to 1 K above the longterm mean. Salinities were measured regionally both above and below mean values up to 1 0/00.

125 Jahre Deutsche Fischereiforschung

In the year of its foundation, in 1870, the German Fisheries Association proposed that a commission should be formed for the strengthening of the German coastal and high sea fisheries by research. The resulting Prussian "Commission zur Erforschung der Deutschen Meere" Commission for Scientific Research on German Seas) in Kiel started its work on July 13th, 1870. With 125 years of organization and scientific continuity, the original institutions were transformed by internal and external influences into the Bundesforschungsanstalt für Fischerei and the Deutsche Wissenschaftliche Kommission für Meeresforschung (Federal Research Center for Fisheries; German Scientific Commission for Marine Research) of today. Their actual fisheries research is of special importance due to the background of increased fisheries activities against decreasing fish stocks.

Makrelen- und Holzmakrelenfänge stimmen zuversichtlich

In order to determine the abundance of incoming year classes of both mackerel and horse mackerel a couple of research vessels in the frame of ICES investigats waters west of the British Isles, the Gulf of Biscay and areas west of the Iberian Peninsula in the first half of each third year. In 1995, Germany took place in these investigations with R.V. "Walther Herwig III" from March 23 to April 18. A total of 100 plankton stations were made using a Gulf - III - Sampier between Fastnet Rock and the Gironde estuary. In addition, 87 fishing stations were occupied by a GOV net. Though fish indications were not fished on purpose large amounts of especially horse mackerel and mackerel were gained in the half hour tows. Besides, boarfish (Capros aper L.), blue whiting, and sprat were found in considerable quantities and numbers in some areas. The hydrographc situation was as expected: The development of a surfaee thermocline created by radiation indieates the collapse of the vertically homogeneous situation of the winter period.

Maßnahmenkatalog für eine ausgewogenere und rationellere Bewirtschaftung der von der deutschen Fischerei genutzten Fischereiressourcen im EG Meer

Obgleich die Nordsee eines der produktivsten Schelfmeere der Welt ist, reichen die Fischereiressourcen nicht aus, um allen zur Zeit aktiven Fischern für die nächsten Jahre ein wirtschaftliches Überleben zu garantieren. Darüberhinaus besteht die Gefahr, daß andauernde Uberfischung zu einer nachhaltigen Schädigung der Fischbestände und des Ökosystems führt. Es ist daher notwendig, zu einem langfristig ausgewogeneren Verhältnis zwischen den Ressourcen und der Intensität der Fischerei zu gelangen. Die Bundesforschungsanstalt für Fischerei in Hamburg hat im Jahr 1993 eine Expertenrunde zu diesem Themenkreis zusammengerufen und eine Zusammenstellung von aus wissenschaftlicher Sicht wünschenswerten und sinnvollen Maßnahmen zum langfristigen Erhalt der Fischbestände in der Nordsee erarbeitet, der im Folgenden der Öffentlichkeit vorgestellt werden soll.

1994: Optimismus nur für den Nordseesprottenbestand

The new German R.V. "Walther Herwig III" joined the International North Sea Bottom Trawl Survey (IBTS) coordinated in the frame or ICES from February 18 to March 22 1994. A total of 354 valid half hour tows were made by seven research vessels from the different ICES members in order to determine the strength of incoming year classes of commercially most important fish species. Preliminary index figures for the stocks under observation of all participating vessels show that only the North Sea sprat stock developed a substantial year class in 1993. In addition, hydrographic data were collected during the survey. These data show the temperatures and salinities of the northern and central North Sea in most parts beneath the mean values during the period under investigation.

Optimistische Prognosen nur für den Schellfisch-, Wittling- und Sprottnachwuchs in der Nordsee

From January 22 to February 12, 1993, "Walther Herwig" participated in the ICES coordinated International Bottom Trawl Survey (IBTS, formerly International Young Fish Survey (IYFS)) in the North Sea. In total all participating nations covered 369 fishing stations, 65 of which were investigated by "Walther Herwig". Preliminary results show that the youngest yearclasses of haddock, whiting, sprat and Norway pout are well above average whereas herring in his second year of life is only average. No signs of a recovery of the North Sea mackerel stock could be detected. The measured temperature data show a more or less mean situation during the period under review.