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.

27. Sitzung des FAO/WHO-Codex-Alimentarius-Komitees für Fische und Fischerzeugnisse

1963 wurde von der FAO und WHO die Codex-Alimentarius-Kommission gegründet, die Lebensmittelstandards, Richtlinien und Vorschriften wie Codes of practice im Rahmen des gemeinsamen FAO/WHO Food Standards Programme erarbeiten sollte. Hauptziel dieses Programmes ist der Schutz der Gesundheit der Verbraucher und die Sicherung fairer Praktiken im Lebensmittelhandel sowie die Koordinierung der Arbeiten zu Lebensmittelstandards, die von international, staatlichen und nicht-staatlichen Organisationen durchgeführt werden.

Einfluss von Reifung und technologischen Behandlungen auf die Proteine des Rogens von Regenbogenforellen (Oncorhynchus mykiss)

The use of differential scanning calorimetry for investigating the yolk proteins of the roe of rainbow trout allows to monitor the influence of maturation and vitellogenesis which modifies the DSC curves with regard to transition temperature and enthalpy. Two endothermic peaks become more and more pronounced with increasing maturation of the roe. However, it is still not known which protein fraction is represented by each of the peaks. DSC curves of yolk protein depend on fish species. They are also influenced by technological treatments. Further investigation is necessary to discover whether or not yolk proteins of other fish species are influenced in the same manner by maturation and vitellogenesis and which protein fraction represent the individual peaks.

Zustand und Entwicklung ausgewählter Fischbestände Einschätzung und Empfehlungen des ICES im Jahr 2004

The state of North Atlantic, Baltic Sea and North Sea commercially exploited fish stocks are assessed annually by the International Council for the Exploration of the Sea (ICES). Estimates of the stock size (biomass), recruitment, landings, current exploitation rates and of future harvesting possibilities are provided for those stocks where sufficient information is available to conduct a full analytical assessment. For all other stocks, only landings and stock trends can be given. This paper presents the development of north-east Atlantic fish stocks which are of general or specific interest for the German fishery and fish industry. Generally, it may be concluded that most pelagic fish stocks, such as herring, sprat, mackerel, and blue whiting, are in good condition, while the majority of the demersal stocks, like cod, plaice or whiting are in critical state. There are, however, a number of remarkable exceptions to this pattern.

Aktivitäten des nationalen Fischereidatenerhebungsprogramms im Jahr 2004

Based on the EU Regulation 1543/2000 for the improvement of quantity and quality of fishery data the Federal Ministry for Consumer Protection, Food and Agriculture has initiated a national data collection programme, executed by three institutions, Federal Research Centre for Fisheries (BFAFi), Federal Agency for Ariculture and Food and the Federal Research Centre Agriculture, co-ordinated by BFAFi. In 2004 samples have been taken from 943 hauls during 29 commercial fishing trips; 357 000 fish have been measured. From 2002 to 2004 the number of length and weight and measurements, and age determinations could increased by 32, 65 and 156 % resp. Pilot inquiries have been carried out to prepare also the collection of economical date of fishing vessels and of fish processing plants from 2006.

Untersuchungen des Zanderbestandes in den deutschen Küstengewässern der Ostsee von 1992 bis 2002

Pike-perch is an important resource for the coastal fishery in the brackish waters of the eastern part of the coast. For the conservation of the stocks regulation measures (minimum landing size, closed season and minimum mesh size) have been introduced since many years. Basic biological material of the last decade sampled from the commercial fishery and for recruitment by a standard trawl survey. For the “Eastern stock” this paper presents the results concerning age distribution, year-class strengths, growth, proportion spawners, natural mortality and yield-per-recruit analyses.

Zustand und Entwicklung ausgewählter Fischbestände: Einschätzung des ICES im Frühjahr 2003

During the spring session of the ICES Advisory Committee for Fisheries Management (ACFM) 48 stocks assessed by 7 Working Groups have been analyzed and reviewed, among these all herring stocks in the ICES area, blue whiting and most demersal stocks in the Baltic, Arctic and North-Western area. As in previous years, ICES recommends a reduction in fishing mortality for a number of stocks or even the establishment of recovery and management plans, to safeguard a continuous development of the stocks towards safe biological limits. ICES recommended a 90% reduction of the cod fishery in the Baltic Sea, while most of the herring stocks are in good condition.

Zustand und Entwicklung ausgewählter Fischbestände: Einschätzung des ICES im Herbst 2003

During the autumn session of the ICES Advisory Committee for Fisheries Management (ACFM) 58 stocks assessed in 7 Working Groups have been analyzed and reviewed, among these the demersal stocks in the North Sea and the Mackerel stock. As in previous years, ICES recommends a reduction in fishing mortality for a number of stocks or even the establishment of recovery and management plans, to safeguard a continuous development of the stocks towards safe biological limits. ICES reiterated last year’s recommendation to close the directed cod fishery and any fishery taking cod as by-catch in the North Sea, west of Scotland and in the Irish Sea. This year, the stocks of plaice in the North Sea, southern hake and southern anglers are (among others) in a critical state and in urgent need of protecting or rebuilding measures. This will again have an enormous impact on almost all mixed fisheries in the European Union.

26. Sitzung des FAO/WHO-Codex-Alimentarius-Komitees für Fische und Fischerzeugnisse

Die 26. Sitzung des Codex-Alimentarius-Komitees für Fische und Fischerzeugnisse fand vom 13. bis 17.Oktober 2003 in Aales und, Norwegen, statt. Die Tagung wurde von 130 Delegierten und Beobachtern aus 47 Mitgliedsstaaten und 5 internationalen Organisationen besucht. Die größten Delegationen stellten Deutschland(7), Thailand (7), Japan (8), USA (11) und Norwegen als Gastgeber (14). Die deutsche Delegation wurde von Dr. Markus Brill (BMVEL) geleitet. Weitere Mitgliederwaren Prof. Jörg Oehlenschläger (BFAFi, Sprecher), Dr. Kristina Ravelhofer-Rotheneder (BMVEL), Dr. Reinhard Schubring (BFAFi), Dr. Mathias Keller (Bundesmarktverband der deutschen Fischindustrie und des Fischgroßhandels e.V.), Petra Weigl (Pickenpack-Hussmann und Hahn Seafood GmbH) und Dr. Ralf Peter Pund (BfR). Die Sitzung, die von Janne Johnson, Staatssekretärin im norwegischen Fischereiministerium, eröffnet wurde, leitete Dr. Bjørn Rothe Knudtsen, Regionaldirektor des norwegischen Direktorats für Fischerei und Aquakultur, Trondheim.

Lage und Entwicklung ausgewählter Fischbestände: Einschätzung des ICES im Juni 2002

During the spring session of the ICES Advisory Committee for Fisheries Management (ACFM) the stocks of the Northern Pelagic and Blue Whiting, North Western, Baltic, Arctic and Deep Sea Working Groups have been analysed and assessed, as well as the Nephrops stocks. As in previous years ICES recommends a reduction in fishing mortality for a number of stocks. Moreover, ICES recommends for many stocks to establish recovery and management plans, to safeguard a continuous development of the stocks towards safe biological limits. Detailed recovery plans were proposed for cod and hake in the North Sea.

10 Jahre Untersuchungen zur Reproduktionsbiologie des Dorsches im Institut für Ostseefischerei

The reproduction biology of cod is one of the main re-search topics of the Institute of Baltic Sea Fisheries at Rostock. It was defined 10 years ago when the Institute was formed. Since then results have been published in a number of publications. This paper summarizes the main results of the past decade ant outlines necessities for future research in cod reproduction biology in the Baltic Sea.

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.

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

Die 25. Sitzung des Komitees für Fische und Fischereierzeugnisse fand vom 3. bis 7. Juni 2002 in Aales und, Norwegen, statt. Die Tagung wurde von 131 Delegierten und Beobachtern aus 41 Mitgliedsstaaten und 2 internationalen Organisationen sowie FAO- und WHO-Personal (4)besucht. Die größten Delegationen stellten Frankreich (7), Thailand (7), USA (10) und Norwegen als Gastgeber (13).Die deutsche Delegation wurde von Dr. Achim Viereck(BMVEL) geleitet. Weitere Mitglieder waren Prof. Jörg Oehlenschläger (BFAFi, Sprecher), Dr. Andrea Sanwidi (BMVEL), Dr. Reinhard Schubring (BFAFi), Dr. Günter Klein (BgVV) und Dr. Jörn Scabell (Frozen Fish International als Vertreter des Bundesverbandes der deutschen Fischindustrie und des Fischgroßhandels). Die Sitzung, die von Peter Gullestad, dem norwegischen Generaldirektor für Fischerei, eröffnet wurde, leitete Dr. Bjorn Rothe Knudtsen, Regionaldirektor des norwegischen Direktorats für Fischerei und Aquakultur, Trondheim.

Zustand und Entwicklung ausgewählter Fischbestände - Einschätzung des ICES im Herbst 2002

During the autumn session of the ICES Advisory Committee for Fisheries Management (ACFM) 58 stocks assessed in six Working Groups have been analysed and reviewed, among these the demersal stocks in the North Sea and the Mackerel stock in the North East Atlantic. As in previous years, ICES recommends a reduction in fishing mortality for a number of stocks or even the establishment of recovery and management plans, to safeguard a continuous development of the stocks towards safe biological limits. ICES recommended the closure of the directed cod fishery and any fishery taking cod as by-catch in the North Sea, west of Scotland and in the Irish Sea. This will have a significant impact on the mixed round fish fisheries targeting haddock and whiting.