Spezifizierungsanalyse des Quecksilbers - ein möglicher Beitrag zur Erforschung der Auswirkungen klimatischer Veränderungen auf die belebte Meeresumwelt

The predominantly occurring chemical forms (species) of mercury (Hg) that occur in the environment are elemental mercury (Hg0), divalent inorganic mercury (Hg2+) and dimethylmercury (CH3HgCH3) and monomethylmercury(CH+3Hg), the latter of which is strongly accumulated by marine organisms. Conversions between the different mercury species provide the basis of the complex distribution pattern of mercury on local, regional, and global scales. An analytical system using hyphenated instrumental techniques has been developed and validated in order to determine inorganic and organic mercury species in marine biota (fish and plankton). It is suggested than mercury species analysis can provide a useful tool to investigate the effects of climate changes on the bio-transformation activity of certain marine microorganisms.

Fischereilich-ökonomische Überlegungen zu Chancen und Risiken in der Garnelenfischerei - am Beispiel des Schollendiscards (Ein Thesenpapier auf der Basis von EU-Studien und Langzeitreihen)

Though economic research is not one of the tasks of the German Federal Research Centre for Fisheries, basic in-formation for such work is available from biologic studies on fish biomass, discards and seasonal abundance of species. Results from EU-studies on brown shrimp fisheries show the effect of discarding juvenile fish, especially plaice, the possibly lost numbers and value of this fish as well as chances of reducing these losses by a timely effort reduction in summer and the use of selective nets throughout most parts of the year. However, it is also made clear, that these costly measures may have no effect on the stocks due to biological compensatory effects observed in strong year classes of plaice e. g. 1996, with high landings and collapsing prices. Therefore sound biological and economic data and methods are needed to assess the economic effects of management measures on fishermen’s situation and markets. Compensations for catch limitations may become inevitable.

Ökonomische Betrachtungen zu kurz- und langfristigen Maßnahmen in der Fischerei. Vorstellung von drei Forschungsprojekten

At present, there is practically no research on fisheries economics in Germany. Due to special interest of a research assistant in the field of land economics at the Institute of Botany of the University of Greifswald two projects on fisheries economics are being carried out, and a Ph. D. thesis on this topic has been finished. Basically two levels must be distinguished: business level and economics. Business economics relate mainly to operational and market analysis, but also to consequences of political measures for a single company. Economical considerations relate to long-term measures. It is important to find a compromise between short-term economical success and stable long-term conditions for the fishery.

Aktuelle Aspekte und Besonderheiten der deutschen Flunderfischerei in der Ostsee im Jahr 2002

Although the fishery on flounder in the German fishery zone in 2002 was characterised by good catch possibilities, a dramatic decrease of landings was observed because of marketing problems and low prices. Due to increasing international fishery pressure on flounder a quota system should be established in the future. The German flounder landings could be increased by a better marketing strategy to meet the optimal requirements for a reliable German quota. For 2003 the stock condition is expected to be good which could ensure a successful flounder fishery. It is necessary to stabilize the present technical measures for a better selection of the codend in the medium term.

Starker Nachwuchsjahrgang 2002 des Herings der westlichen Ostsee

Several fishery independent estimates of the year-class strength are necessary for the assessment and the management of the total fish stock. An index for the year-class strength of the spring spawning herring in the western Baltic Sea is estimated on the basis of larvae surveys in the most important spawning ground. The results indicate a strong year-class 2002.

Technische Empfehlungen für den künftigen Einsatz von Plattfischsteerten in der Ostsee

Die Grundschleppnetzfischerei in der Ostsee konzentriert sich im wesentlichen auf den Fang von Dorsch- und Plattfisch. Neben der Dorschfischerei gibt es auch beim Fang von Plattfisch gebiets- und zeitweise erhebliche Beifänge an untermaßigen Fischen, die verworfen werden müssen. Für beide in Form und Verhalten sehr unterschiedlichen Fischarten können bis dato die gleichen Steerte eingesetzt werden. Um die durch diese Mix-Fischerei an der südlichen Ostseeküste gegebenen Probleme zu verdeutlichen und auf eine zukünftig differenzierte Behandlung für die technischen Maßnahmen zur Verbesserung der Selektivität hinzuwirken, werden seit 1998 vergleichende Untersuchungen mit Schleppnetzsteerten unterschiedlicher Konstruktion durchgeführt.

WEFTA-Laborvergleichsuntersuchungen zur pH-Bestimmung in Fischerei-Erzeugnissen - Eine gemeinsame Aktion der Western European Fish Technologists' Association

12 samples (6 original samples and 6 diluted samples) were analysed by 14 WEFTA laboratories for their pH values in an inter-laboratory comparison exercise. As a result it can be stated that the majority of participating laboratories could determine the pH values very exactly. The pH values obtained are ranging only little around the calculated mean (less than 0.1 pH unit). It could also be demonstrated that the participating institutes could analyse both, pH values in fishery products and aqueous salt solutions. However, also in this exercise a number of outliers and deviating values have been detected. Therefore it is of utmost importance to calibrate the pH electrodes in regular intervals and to maintain them carefully. Intra-laboratory comparison measurements are recommended to detect weak points.

32. Jahretagung der West European Fish Technologists Association

Die West European Fish Technologists Association (WEFTA, gegründet 1970) ist ein Zusammenschluß von Europäischen Insti-tuten, die auf dem Gebiet Fischerei, Fischqualität und -verarbeitung arbeiten und forschen. Ziele der WEFTA ist der Informa-tionsaustausch zwischen Wissenschaftlern und Fischindustrie sowie die Ausweitung und Verbesserung der Zusammenarbeitunterschiedlicher Interessengruppen und Instituten in Projekten.

Neues Institut für Fischereitechnik und Fischqualität. Zusammenlegung der Institute für Fischereitechnik und Biochemie und Technologie

Entsprechend dem Rahmenkonzept für die Bundesforschungsanstalten im Geschäftsbereich des damaligen Bundesministeriums für Ernährung, Landwirtschaft und Forsten vom 12. 6. 1996 ist an der Bundesforschungsanstalt für Fischerei in Hamburg die Anzahl der Institute von fünf auf vier zu reduzieren. Das ab 1. 1. 2001 neu gebildete Institut für Fischereitechnik und Fischqualität (IFF) nimmt die Forschungsaufgaben der beiden bisherigen Institute für Fischereitechnik (IFH) sowie Biochemie und Technologie (IBT) wahr. Damit bietet sich für das aus zweivergleichsweise kleinen Instituten hervorgegangene IFF die Möglichkeit, in einem integrierten Ansatz Fische, Krebse und Weichtiere auf verschiedenen Stufen der Produktions- und Verarbeitungskette zu untersuchen und zu bewerten. Fangprozess und Folgebehandlung der Fangobjekte werden dadurch ganzheitlich betrachtet, was sich nicht zuletzt in Maßnahmen zur Qualitätserhaltung und -verbesserung von Fischen und Fischereierzeugnissen niederschlagen soll.

Die europäischen Krabbenanlandungen der letzten Jahre: Deutschland Nr. 1

Fishery on brown shrimp has developed towards one of the most important fisheries in the North Sea area in economic terms. Statistical data on European wide landings have been gathered by a working group of the International Council for the Exploration of the Sea. They show relatively stable shares of approximately 50% for Germany, 38% for the Netherlands and 8% for Denmark. Further production originates from Great Britain, France and Belgium. The new log-book regulation of the EU will give similar data improved by better information on fishing areas and fishing effort.

Keine überdurchschnittlichen Nachwuchsjahrgänge bei den Nutzfischen der Nordsee

In January/February 2001, Germany participated with “Walther Herwig III” in the International Bottom Trawl Survey (IBTS) of ICES by contributing 70 half hour tows with the Grande Ouverture Verticale Bottom Trawl (GOV), 78 hydrographic stations, and 88 catches with the Method-Isaac-Kidd net (MIK), mostly in the central and northern North Sea. In total, 368 fishing stations by means of the GOV were covered by the international fleet. Preliminary results indicate that only indices for herring, whiting, and – to some degree – haddock are in the long-term mean. In contrast, the index for cod gives reason to serious concern. In addition, indices for both mackerel and Norway pout do not show any signs for an increasing strength of these stocks. Oceanographic data show that in comparison with the data from 1995 onwards actual temperatures and salinities are in the normal range. However, mean water temperatures of this short period are about more than a half degree above the long-term means of the period 1961 to 1990.

Zusammenhang zwischen Schadstoffen aus der Elbe und missgebildeten Fischembryonen in der Deutschen Bucht.

The trends of malformation prevalence in embryos of dab, Limanda limanda, in the southern North Sea after the year 1990 mirrored the drop in major pollutants in the rivers draining into the German Bight. Despite this general decline we detected a pollution event in the southern North Sea in winter 1995/1996 employing the prevalence of malformations in dab embryos as an indicator. An abrupt rise in malformation prevalence in the embryos of dab, corresponded to a dramatic increase in DDT levels in parent fish from the same area, indicating a hitherto unnoticed introduction of considerable quantities of DDT into the system. This input could be traced back to discharges of unknown origen into the River Elbe.

Kritische Betrachtung der Begriffe Fischereiaufwand und Fangkraft mit dem Ansatz einer Neubewertung

In order to restore the balance between available fish res-sources and catch capacities in the marine waters of the EU, the European Commission has introduced so-called Multiannual Guidance Programmes (MAGPs) within the frame work of the Common Fisheries Policy (CFP). However, the non-quantified relation between fishing effort and fishing power of a vessel has proved to be one of the most difficult problems. The present contribution suggests to substitute traditional but non-quantifying methods by including the real catch results into the models.

Sensibilität von Seefischen an Bord. Teil 3: Untersuchungen an demersalen Fischarten der Barentssee

In previous papers the sensibility of pelagic and demersal fishes caught at depth of up to 80 m was reported. This paper deals with the sensitiveness of flatfishes, gadids, and redfish caught at depth between 260 and 450 m and with trawling times between 1 and 6 h. The sensitiveness of the fishes was tested according to the method described in previous publications (Münkner et. al. 1998) after 10 min keeping in running sea water and after 1h bulk storage respectively. The sensitiveness of the fishes increased from cod to saithe to haddock. Surprisingly American plaice and Greenland halibut turned out to be very sensitive, far more sensitive than plaice and dab caught at lower depths in the North Sea. This was indicated by the high amount of animals showing rigor already after a trawling time of 2 hand 10 min of keeping in seawater. After 1 h of bulk storage and increasing trawling time sensitiveness of all fishes decreased, as expected, significantly. Besides mechanical encroachments the main problem for the fishes caught at greater depths was the gas supersaturation in the blood and tissue causing blockage of the gill capillary vessels, exophthalmus, visible gas bubbles in the skin and eyes, and in some cases protusion of the intestines through the snout due to rapid dilatation of the swimbladder.

30. Jahrestagung der "WestEuropean Fish Technologists' Association" in Torshavn, Faroer

In der West European Fish Technologists’ Association (WEFTA) arbeiten zahlreiche europäische Institute zusammen, die sich mit Fisch als Lebensmittel oder mit Fischtechnologie befassen. Ziel der WEFTA ist es, einen Austausch von Informationen über Forschung und ihre Ergebnisse europaweit möglich zu machen. Die Jahrestagungen sind eine gute Gelegenheit, Einblick in die Arbeiten anderer Institutionen zu erhalten und europäische Kontakte zu knüpfen. Die Tagungen sind besonders interessant für junge Wissenschaftler, die hier ihre Ergebnisse einem grösseren Publikum vorstellen konnen.