Johann Heinrich von Thünen: Leben und Werk des Namenspatrons des neuen Bundesforschungsinstituts für Ländliche Räume, Wald und Fischerei

A new concept for resource oriented federal research within the competence of the German Ministry of Food, Agriculture and Consumer Protection was implemented in 2008. The Johann Heinrich von Thünen-Institute, Federal Research Institute for Rural Areas, Forestry and Fisheries is one of 4 newly established large scale federal research institutions. It comprises the former Federal Research Centre for Fisheries, the Federal Research Centre for Forestry and Forest Products and large parts of the Federal Agricultural Research Centre. The institute is named after Johann Heinrich von Thünen, a famous national economist and social reformer of the 19th century. He developed the first serious treatment of spatial economics (the so-called Thünen rings) and the basics of the theory of the natural pay.

Raumordnung in der AWZ: Mittlere Anlandungen der deutschen und internationalen Fischereiflotten aus deutschen Nordseegewässern im Zeitraum von 2000 bis 2004

The pressure of users other than shipping and fishery on the national EEZs for territorial claims has increased in recent years. So it becomes necessary to carry out a spatial planning for which all users have to indicate their recent and planned future activities. For the German waters in the North Sea a first attempt was made to calculate the mean international landings for the commercially important fish and crustacean species on the spatial scale of ICES-rectangles. The relationships between the German and international landings per species are listed in a table and the distribution of the landings for each species within the area are shown in 13 figures.

Untersuchungen zur chemischen Zusammensetzung und Nematodenbelastung von Stinten (Osmerus eperlanus L.)

Smelt (Osmerus eperlanus L.) from the river Elbe has a long tradition as local food speciality. It is offered baked or fried every year during spring in many restaurants along the river. Information about the composition of the edible part and its changes during fishing season are scarce. In earlier days the fish was mostly sold by local fisherman directly after catch. Today the fish is also offered as ungutted fresh fish in ice on the whole sale market. The freshness of this fish has not been studied. Smelt from the river Elbe is known to contain nematode larvae (Pseudoterranova decipiens) in the muscle meat. Actual quantitative data on the abundance and prevalence in the commercially offered ice stored fish are missing.

Die EU-Förderung der Fisch verarbeitenden Industrie und das EU-Datenerhebungsprogramm

A considerable amount of national EU funds for supporting fisheries has been transferred to the German fish processing in-dustry. The recently ratified European Fisheries Fund (EFF) again provides a significant sum. Yet the EU is lacking a data pool of sufficient precision, which is required as a basis to develop apt EU regulations in the future. Regulation No. 1639/2001 of the EU Commission commits the member states to collect these data. In this paper specifics of the data to be collected and the collection procedure are presented and linked to the CFP and to characteristics of the German fish processing industry.

28. Sitzung des FAO/WHO-Codex-Alimentarius-Komitees für Fische und Fischereierzeugnisse

Die 28. Sitzung des Codex-Alimentarius-Komitees für Fische und Fischereierzeugnisse fand in Peking, China, vom 18. bis 22. September 2006 statt. Das Komitee folgte damit der in der letzten Sitzung ausgesprochenen Einladung der chinesischen Regierung und dem Ziel, die Codex-Sitzungen in verschiedenen Teilen der Welt abzuhalten. Geleitet wurde die Sitzung von Dr. Bjørn Røthe Knudsen, Regionaldirektor der norwegischen Behörde für Lebensmittelsicherheit. Professor Li Xiaochuan von der chinesischen Akademie für Fischforschung nahm die Rolle des Co-Chairman ein. Insgesamt 140 Delegierte, die 44 Mitgliedstaaten, die EU und eine internationale Organisation vertraten, nahmen an dieser Sitzung teil. Folgende Punkte wurden auf der diesjährigen Codex-Komitee-Sitzung diskutiert: 1. Erweiterung des Standards für Sardinen und sardinenähn-liche Erzeugnisse 2. Bearbeitung des Entwurfs eines Standards für Störkaviar 3. Überarbeitung des Entwurfs eines Standards für lebende und rohe Muscheln 4. Verhandlung über den Entwurf des Standards für geräu-cherten Fisch 5. Code of Practice für Fische und Fischereierzeugnisse 6. Zukünftige Arbeiten

Veränderungen der Farbe und thermischen Stabilität der Muskelproteine von Räucherforellen während der Kühllagerung

The aim of the investigation was to prove if different farming conditions like conventional and organical farming of rainbow trout may cause differences in quality which are detectable by physical methods such as colour measurement and differential scanning calorimetry. Colour measurement revealed remarkable differences in lightness. Smoked trouts originating from conventionally farmed fish were much lighter than those of organically farmed trouts. This difference in L* could already be found when colour measurements were taken on the raw material. However, during chilled storage differences were equalized. Redness and yellowness were not significantly influenced by farming and did not change remarkably during chill storage. Based on earlier investigations on changes in thermal stability caused by heating, DSC curves of smoked trout could be used to verify that the core temperature of smoked fish had reached at least 60 °C during hot smoking process. This temperature is demanded by the guidelines of the German Food Code. In the DSC curves only the actin peak was still visible. All other proteins were obviously denatured during the hot smoking. When DSC curves were taken from smoked trout after different durations of chilled storage it could be seen that the denaturation temperature of actin decreased almost linearly with progression of storage time.

Fang, Anlandungen, Discard und Bestand der Nordsee-garnele (Crangon crangon L.)

Landings of brown shrimp (Crangon crangon) for human consumption are not the only part that is taken from the North Sea shrimp stocks. Small amounts of industrial shrimps taken in the second half of a year in Germany add as well to the total amount that is taken from the stocks as the moribund animals discarded all over the year during the first sieving process on board, as the cooked and discarded ones in the second sieving on board and as those from the third sieving process ashore normally being crushed and used for animal feed stuff. All these fractions of the total catch of brown shrimps give a total of approximately 74 000 tonnes that were taken from the North Sea in 2005. Nevertheless, due to low predator abundance and changing climate conditions Crangon stocks show no signs of overexploitation so far with increasing LPUE values in the north-eastern part of the German Bight and decreasing ones in the south-east and Channel. There is the need of further investigations of these changes in the life history and distribution of shrimp as well as in the fishing behaviour and effort of the shrimp fleets .

30. Sitzung des Codex Alimentarius Komitees für Fische und Fischerzeugnisse in Agadir, Marokko, vom 28.9. bis 2.10.2009

The Codex Committee on Fish and Fishery Products held its 30th Session in Agadir, Morocco from 28 September to 2 October 2009, at the kind invitation of the Government of Morocco. The Session was chaired by Dr Bjørn Røthe Knudsen, Regional Director of the Norwegian Food Safety Authority. The Session was attended by 218 delegates representing 78 Member States, one Member Organization (EC) and 1 international organization.

Guter Nachwuchsjahrgang 2004 des Herings der westlichen Ostsee, des Kattegats und Skagerraks (ICES-Gebiete IIIa und 22 – 24)

Several fishery independent estimates of the year-class strength are necessary for the assessment and the ma-nagement 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 good year-class 2004.

Maifische an der deutschen Nordseeküste - zum Auftreten von Finte (Alosa fallax) und Alse (Alosa alosa)

Quantitative data on twaite shad are collected annually in spring and autumn since 1974 by the Demersal Young Fish Survey. Results for occurrence of these anadromous species show that twaite shad has been caught in the entire Wadden Sea area despite of the poorly suited 3-m shrimp beam trawl applied in the survey. Regional differences occur: Only sporadic catches are observed in the northern part of the German Wadden Sea, while more frequent ones occurred southwards and in the East Frisian Islands region. The obvious recent increase of abundance of Alosa fallax in spring allows for a lower ranking in the Red List of Endangered Species, while Allis shad (Alosa alosa) requires the same classification, as it was the never caught during the thirty years of surveys.

Die Überwachungsprogramme der internationalen Meeresschutzkonventionen für Nord- und Ostsee

The international conventions for the protection of the marine environment of the North-east Atlantic Ocean including the North Sea (OSPAR) and the Baltic Sea (HELCOM) as well as the International Council for the Exploration of the Sea (ICES) have modified their structures in the recent years towards a strategy directed approach. Committees and working groups have partly changed only their names but in many cases also the scope of their subjects. In the last two years activities have been initiated to coordinate the tasks of the marine conventions and the European Union and to merge them as much as meaningful and practicable, under a common EU Marine Strategy. This article will reflect how the organisational structures have changed since the last restructuring in the first half of the nineties, and how the contaminant and bioeffect monitoring activities of the Federal Research Centre for Fisheries are implemented in these international conventions.

Entwicklung einer einfachen und schnellen Analysenmethode für Kohlenmonoxid in Fisch und Durchführung orientierender Untersuchungen

Treatment with gases containing CO, misleadingly called “tasteless smoke” or “clear smoke”, prior to freezing of fish like tuna, tilapia and swordfish (to name only a few of these species that are characterised by an intensive coloration of flesh) stabilise the fresh red colour of muscle also after thawing and suggest consumers non-existing freshness. In the European Union, carbon monoxide is excluded from being a permitted additive and therefore this handling is not allowed. Notwithstanding of the clear legal position, producers and traders are trying to establish CO treated fish on the market. In the case of taking legal measures the food control laboratories have to provide evidence that fish has been treated by CO and therefore a respective method is necessary. The method of determination of carbon monoxide in fish flesh presently applied requires considerable material and mechanistic effort to detect CO by GC after catalytic transformation into methane. The aim of our work was a direct detection of CO using suitable sensor technology. Mechanistic requirements and results of preliminary investigations to detect carbon monoxide in fish flesh will be described.

Die Reproduktion von Dorschen (Gadus morhua L. und Gadus morhua callarias L. ) in der Ostsee unter besonderer Berücksichtigung der Arkonasee. Teil I: Allgemeiner Verlauf des jährlichen Reifeprozesses und der Laichaktivitäten in den verschiedenen Gebieten

From 1993 to 2003 special surveys were conducted to analyse temporal and spatial aspects of the spawning activities of cod in the Baltic Sea. The ICES advice for cod in the Baltic Sea is based on yearly stock assessments of two separate stocks the western (SD 22 – 24) and the eastern stock (SD 25 – 32). Both stocks are characterized by different spawning seasons. The general progression of the maturity suggests that two types of development can be distinguished. In the western Baltic Sea (SD 22) the maturity development is temporal stable, with a relative short, main spawning period from March to April - spring spawner. In the Arkona Sea and Bornholm Basin the main spawning season starts in June and probably finishes in September - summer spawner. The proportion of spawners in summer is significantly higher than in spring in the Arkona Sea and Bornholm Basin. This again underlines the importance of the Arkona Sea for the reproduction success of the eastern Baltic cod stock. The analysis furthermore show, that the proportion of male spawners was significantly higher than the proportion of female spawners in all areas and the investigated months. This observation suggests that the reproductive success is only limited by the number of female cod which participates in the spawning process.

Die Reproduktion von Dorschen (Gadus morhua L. und Gadus morhua callarias L.) in der Ostsee unter besonderer Berücksichtigung der Arkonasee. Teil II: Statistische Analysen zum Anteil reproduktiv aktiver Dorsche in Bezug auf gebietsspezifische Unterschiede und Gemeinsamkeiten, sowie deren mögliche Ursachen.

Surveys were conducted to analyse temporal and spatial aspects of the spawning activities of cod in the Baltic Sea from 1993 to 2003. Part I of the article describes the general maturity development and the spawning activities in the western Baltic Sea, the Arkona Sea and the Bornholm Sea. The studies suggest that two types of spawner can be distinguished, the spring spawner in the western Baltic Sea and the summer spawner in the Arkona Sea and the Bornholm Basin. The descriptive analysis is supported by statistical studies presented in this article. It is shown, that the proportion of spawning individuals is significantly higher in summer than in spring in the ArkonaSea and the Bornholm Sea. Furthermore, it is shown that reproductive mixing of both types of spawner is possible in the Arkona Sea in May/June due to the hydrographical conditions in the Arkona Sea which were suitable in 8 of 10 years for successful reproduction of both Baltic cod stocks, and that spatial expansion of spawning activities of the eastern Baltic cod stock into the Arkona Sea is positive correlated with the size of spawning stock in the Bornholm Sea.

Wer fischt was? – Gemischte Bodenfischereien und ihre Auswirkungen auf die wichtigsten Nutzfischbestände in der Nordsee

Cod, haddock, whiting, saithe, plaice, sole and Norway lobster are 7 main target species of the demersal mixed fisheries in the North Sea, Skagerrak and Eastern Channel. Gadoids and Norway lobsters are mainly taken in the nor-thern North Sea by towed gears except beam trawls while the flatfish fisheries are conducted in the southern North Sea mainly using beam trawls. Recently, the central North Sea appears less fished by demersal gears. Towed nets including seines and beam trawls equipped with meshes of more than 100 mm resp. more than 80 mm were identified as the main gears effecting the depleted cod and reduced plaice stocks. The saithe sector, using towed nets with meshes of more than110 mm, longlines, gill nets and others, appears to affect the 7 species to a lesser extend. These results support the interim effort limitations by gear types, vessel and month as enforced by the European Commission since 2003. TAC regulations alone are considered inefficient to sustainably harvest stocks by mixed fisheries. A fleet-effort management method is developed estimating the fleets’ effects based on the sum of partial exploitation rates of the species in mixed fisheries weighted by the ratio of the precautionary reference Bpa and the actual SSB size as ecological quality objective. Applying such fleet effort management could result in increased catch possibilities of some stocks by fleets selecting mainly few and non-overexploited stocks while respecting precautionary management constraints in minimum SSB or maximum exploitation rates at the same time.