994 resultados para Sea mussels


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The development of longline cultures for blue mussels (Mytilus edulis) at the German North Sea coast has been under way since 2001. It has turned out to be a successful and innovative method for the rearing of seeding mussels. The comparison of different tested longline types has proved that single longtubes carrying net collectors are the most stable system given the dynamic conditions in the Jade. Artificial collectors were settled by a large number of mussel larvae. Important settling took place between May and July, with 11 000 to 64 000 individuals per meter collector. The shell length of suspended mussels increased in their first summer at an average of 1.2 mm per week. Between the end of August until the end of September a mean of 2 to 9 kg mussels per meter equalling 4500 to 20 300 individuals per meter were harvested. Relayed on bottom cul-tures the mussel seed continued to grow and could be marketed as consumption mussels after their second summer.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A concept for joint research on aquaculture in the Baltic Sea area is presented. It consists of three major parts, the promotion of an aquaculture-based-fisheries, the development of low-output land-based aquaculture systems, and the search for sustainably produced substances from aquatic organisms to be used for different processes. They include substitutes for feeding stuffs or products of importance for medical, biotechnological and industrial applications.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

ENGLISH: Intensification of the Azores high pressure cell in mid-year, with concomitant air flow from the Caribbean into the Pacific, is shown to be responsible for a secondary minimum of precipitation observed along the tropical Pacific coast of the Americas, and to have a measurable effect on wind and precipitation several hundred kilometers offshore. SPANISH: La intensificación de la célula de alta presión de las Azores a mediados del año, y la corriente de aire concomitante que entra al Pacífico procedente del Caribe, se demuestra que es la causante de un mínimo secundario de precipitación observado a lo largo de la costa tropical de las Américas en el Pacífico y que tiene un efecto mensurable sobre el viento y la precipitación varios cientos de kilómetros mar afuera. (PDF contains 23 pages.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

ENGLISH: Isograms of sea surface temperature (OC) have been produced for 1949-1968 for the areas of the eastern Pacific Ocean in which the majority of the skipjack catch is taken. These are in the immediate coastal zone, California (35° N) to Chile (20 0 S), and the Revillagigedo and Galapagos Islands groups. Skipjack occurrence and apparent abundance (as CSDF, i.e., catch per standard days fishing, standardized in purse-seiner units) for 1951-1968 were then superimposed on the surface temperature isograms. Results show that skipjack occur at surface temperatures> 17° C but with the majority between 20°-30° C. Apparent abundance at CSDF > 1 ton/day is normally Iimited to 20°29° C water, except in two areas in certain years; from the Gulf of Tehuantepec to Cape Mala rates of 1-9 tons/day are relatively common at 29°-30° C, and off Chimbote (Peru) occasionally >9 tons/day are recorded down to 18° C. As expected there were no apparent relationships between annual thermal conditions in the coastal zone and skipjack abundance (total catch or indices of abundance) in the same or 2 subsequent years. An Appendix to the report determines the quantitative relationships between surface temperature and skipjack abundance in relatively small areal strata in Baja California waters in 1955 and 1958. Relationships generally appeared significant and opposite in these years when temperatures were respectively anomalously cold and warm. SPANISH: Se han producido isogramas de la temperatura de la superficie del mar (OC) para 1949-1968 correspondientes a las áreas del Océano Pacífico oriental en donde se obtiene la mayor parte de la captura de barrilete. Estas se encuentran ubicadas en la zona costanera inmediata, desde California (35°N) hasta Chile (200S) y en las Islas Revillagigedo y Galápagos. La ocurrencia de barrilete y su abundancia aparente (expresada como CDSP standardizada en unidades de cerqueros) para 1951-1968 fueron luego superpuestas en los isogramas de la temperatura superficial. Los resultados demuestran que el barrilete aparece en temperaturas superficiales de > 17°C pero la mayoría entre los 20°C-30°C. La abundancia aparente de la CDSP > 1 tonelada/día se limita normalmente a aguas de 20°-29°C, excepto en dos áreas en ciertos años; desde el Golfo de Tehuantepec a Cabo Mala las tasas de 1-9 toneladas/día son relativamente comunes en los 29°-30°C, y frente a Chimbote (Perú) se registran ocasionalmente> 9 toneladas/día a una temperatura tan fría como de 18°C. Como era de esperarse no existió una relación aparente entre las condiciones térmicas anuales de la zona costanera y la abundancia del barrilete (captura total o índices de abundancia) en el mismo año o en los 2 años siguientes. Un Apéndice del informe determina la relación cuantitativa entre la temperatura superficial y la abundancia del barrilete en un estrato de áreas relativamente pequeño en las aguas de Baja California en 1955 y 1968. Las relaciones generalmente aparecieron significativas y opuestas en esos años cuando las temperaturas fueron respectivamente anómalamente frías y calientes. (PDF contains 53 pages.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To improve the cod stocks in the Baltic Sea, a number of regulations have recently been established by the International Baltic Sea Fisheries Commission (IBSFC) and the European Commission. According to these, fishermen are obliged to use nets with escape windows (BACOMA nets) with a mesh size of the escape window of 120 mm until end of September 2003. These nets however, retain only fish much larger than the legal minimum landing size would al-low. Due to the present stock structure only few of such large fish are however existent. As a consequence fishermen use a legal alternative net. This is a conventional trawl with a cod-end of 130 mm diamond-shaped meshes (IBSFC-rules of 1st April 2002), to be increased to 140 mm on 1st September 2003, according to the mentioned IBSFC-rule. Due legal alterations of the net by the fishermen (e.g. use of extra stiff net material) these nets have acquired extremely low selective properties, i. e. they catch very small fish and produce great amounts of discards. Due to the increase of the minimum landing size from 35 to 38 cm for cod in the Baltic, the amount of discards has even increased since the beginning of 2003. Experiments have now been carried out with the BACOMAnet on German and Swedish commercial and research vessels since arguments were brought forward that the BACOMA net was not yet sufficiently tested on commercial vessels. The results of all experiments conducted so far, are compiled and evaluated here. As a result of the Swedish, Danish and German initiative and research the European Commission reacted upon this in June 2003 and rejected the increase of the diamond-meshed non-BACOMA net from 130 mm to 140mm in September 2003. To protect the cod stocks in the Baltic Sea more effectively the use of traditional diamond meshed cod-ends with-out escape window are prohibited in community waters without derogation, becoming effective 1st of September 2003. To enable more effective and simplified control of the bottom trawl fishery in the Baltic Sea the principle of a ”One-Net-Rule“ is enforced. This is going to be the BACOMA net, with the meshes of the escape window being 110 mm for the time being. The description of the BACOMA net as given in the IBSFC-rules no.10 (revision of the 28th session, Berlin 2002) concentrates on the cod-end and the escape window but only to a less extent on the design and mesh-composition of the remaining parts of the net, such as belly and funnel and many details. Thus, the present description is not complete and leaves, according to fishermen, ample opportunity for manipulation. An initiative has been started in Germany with joint effort from scientists and the fishery to better describe the entire net and to produce a proposal for a more comprehensive description, leaving less space for manipulation. A proposal in this direction is given here and shall be seen as a starting point for a discussion and development towards an internationally uniform net, which is agreed amongst the fishery, scientists and politicians. The Baltic Sea fishery is invited to comment on this proposal, and recommendations for further improvement and specifications are welcomed. Once the design is agreed by the Baltic Fishermen Association, it shall be proposed to the IBSFC and European Commission via the Baltic Fishermen Association.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Daily sea surface temperatures have been acquired at the Hopkins Marine Station in Pacific Grove, California since January 20, 1919.This time series is one of the longest oceanographic records along the U.S. west coast. Because of its length it is well-suited for studying climate-related and oceanic variability on interannual, decadal, and interdecadal time scales. The record, however, is not homogeneous, has numerous gaps, contains possible outliers, and the observations were not always collected at the same time each day. Because of these problems we have undertaken the task of reconstructing this long and unique series. We describe the steps that were taken and the methods that were used in this reconstruction. Although the methods employed are basic, we believe that they are consistent with the quality of the data. The reconstructed record has values at every time point, original, or estimated, and has been adjusted for time-of-day variations where this information was available. Possible outliers have also been examined and replaced where their credibility could not be established. Many of the studies that have employed the Hopkins time series have not discussed the issue of data quality and how these problems were addressed. Because of growing interest in this record, it is important that a single, well-documented version be adopted, so that the results of future analyses can be directly compared. Although additional work may be done to further improve the quality of this record, it is now available via the internet. [PDF contains 48 pages]

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This Green Guide provides a brief summary of the alarming evidence of changing climate in the Cayman Islands. As we illustrated in our first Green Guide (2008), our lives on these three magical islands are intimately connected to the land and the surrounding sea. Our economy depends on keeping our islands healthy, because our coral reefs, our beaches, our natural heritage, all draw many thousands of overseas visitors to our shores. It is our responsibility, as stakeholders sharing this beautiful environment, to do what we can to minimise our impact upon it... [PDF contains 32 pages]

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The atlanto-scandian herring consists of two major stocks, i.e. the Icelandic summer spawner and the Norwegian spring spawner. Both stocks have recovered well after complete collapse in the seventies and allow for a controlled fishery. The total allowable catch of the Norwegian spring spawner is currently 1.3 mill. t. The resumption of the fishery is accompanied by an annual and multi-national survey with Norwegian, Faeroe Islands, Icelandic and Russian contribution. In 1998 the EU will contribute to the survey with the Swedish vessel ”Argos” and in 1999 with the ”Walther Herwig III” under Dutch, Swedish and German participation. About half of the survey costs are covered by the EU by means of a funded study, the other half is contributed by the participating nations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Im August 1997 wurde an Bord des FFS „Walther Herwig“ ein Eislagerversuch mit Kabeljau aus der Barebtssee durchgeführt. Die Fische wurden in täglichem Abstand auf ihre chemischen, physikalischen, sensorischen und mikrobiologischen Eigenschaften hin untersucht. Die analytischen Daten wurden jeweils mit den Tagen in Eis korreliert. Es erwies sich, daß die Werte vom Fischtester VI sowie RT Frischetester, von Dimethylamin- und Trimethylaminoxidstickstoff, die Qualitätseinstufung anhand des EUQualitätsbewertungsschemas, die sensorische Bewertung von gegarten Filetproben und die Gesamtkeimzahl auf der Haut am besten mit den im Eis verbrachten Tagen korrelierten. Die guteKorrelation zwischen sensorischen und instrumentell ermittelten Daten läßt in gewissem Umfang einen Ersatz von Sensorikdaten durch instrumentell ermittelten zu.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

HIGHLIGHTS FOR FY 2005 1. Assisted with a study to assess hurricane impacts to Gulf sturgeon critical foraging habitat. 2. Documented Gulf sturgeon marine movement and habitat use in the Gulf of Mexico. 3. Documented Gulf sturgeon spawning with the collection of fertilized eggs in the Apalachicola River, Florida. 4. Documented Gulf sturgeon spawning with the collection of fertilized eggs in the Yellow River, Florida. 5. Assisted with benthic invertebrate survey at Gulf sturgeon marine foraging grounds. 6. Implemented Gulf Striped Bass Restoration Plan by coordinating the 22nd Annual Morone Workshop, leading the technical committee, transporting broodfish, and coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system. 7. Over 87,000 Phase II Gulf striped bass were marked with sequential coded wire tags and stocked in the Apalachicola River. Post-stocking evaluations were conducted at 45 sites in the fall and spring and 8 thermal refuges in the summer. 8. Completed fishery surveys on 4 ponds on Eglin AFB totaling 53 acres, and completed a report with recommendations for future recreational fishery needs. 9. Completed final report for aquatic monitoring at Eglin AFB from 1999 to 2004. 10. Completed a field collection of the endangered Okaloosa darter to be incorporated into a status review to be completed in FY06. 11. Provided technical assistance to the Region 4 National Wildlife Refuge (NWR) program on changes to the fishery conservation targets for the region. Also provided technical assistance to four NWRs (i.e., Okefenokee NWR, Banks Lake NWR, St. Vincent NWR, and St. Marks NWR) relative to hurricanes and recreational fishing. 12. A draft mussel sampling protocol was tested in wadeable streams in Northwest Florida and southwest Georgia, and an associated field guide, poster, and Freshwater Mussel Survey Protocol and Identification workshop were completed in FY05. 13. Implemented recovery plan and candidate conservation actions for 14 listed and candidate freshwater mussels in the Northeast Gulf Watersheds. 14. Initiated or completed multiple stream restoration and watershed management projects. A total of 7.5 stream miles were restored for stream fishes, and 11 miles of coastline were enhanced for sea turtle lighting. A total of 630 acres of wetlands and 2,401 acres of understory habitat were restored. 15. Conducted a watershed assessment to develop a threats analysis for prioritizing restoration, protection, and enhancement to natural resources of Spring Creek, Georgia and Canoe Creek, Florida. 16. Continued the formation of an Unpaved Road Interagency Team of Federal, State, and local agencies in Northwest Florida to promote stream protection and restoration from unpaved road sediment runoff. Began the development of a technical committee agreement. 17. Conducted Alabama Unpaved Road Inventory within the Northeast Gulf Ecosystem. Data collection will be completed during FY06. 18. Finalized the development of two North Florida hydrophysiographic regional curves for use by the Florida Department of Transportation (DOT) and others involved with stream restoration and protection. Initiated the development of the Alabama Coastal Plain Riparian Reference Reach and Regional Curves for use by the Alabama Department of Environmental Management (ADEM). 19. Provided technical assistance in collecting data, analysis, and thesis formulation with Troy University, Alabama, to identify the influence of large woody debris in southeastern coastal plain streams. 20. Completed pre- and post-restoration fish community monitoring at several restoration projects including Big Escambia Creek, Magnolia Creek, and Oyster Lake, Florida. 21. Established a watershed partnership for the Chipola River in Alabama and Florida and expanded development and participation in the Spring Creek Watershed Partnership, Georgia. 22. Continued to identify barriers which inhibit the movement of aquatic species within the Northeast Gulf Ecoregion. 23. Completed a report on road crossing structures in Okaloosa darter streams to guide the closure/repair/maintenance of roads to contribute to recovery of the endangered species. In cooperation with Three Rivers RC&D Council, fish passage sites identified in the report were prioritized for restoration. 24. Monitored Aquatic Nuisance Species in the Apalachicola River and tested the sterility of exotic grass carp. 25. Multiple outreach projects were completed to detail aquatic resources conservation needs and opportunities. Participated in National Fishing Week event, several festivals, and school outreach.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

HIGHLIGHTS FOR FY 2004 1. Completed the second of a 3-year Gulf sturgeon population estimate on the Escambia River, Florida. 2. Completed the first of a 2-year Gulf sturgeon population estimate on the Apalachicola River, Florida. 3. Conducted Gulf sturgeon presence-absence surveys in three other Florida river systems. 4. Documented Gulf sturgeon marine habitat use in the near shore waters of the Gulf of Mexico. 5. Identified environmental threats to Gulf sturgeon spawning habitat in the Choctawhatchee River, Florida. 6. Initiated a study to document Gulf sturgeon spawning with the collection of fertilized eggs in the Yellow River, Florida. 7. Implemented Gulf Striped Bass Restoration Plan by coordinating the 21st Annual Morone Workshop, leading the technical committee, transporting broodfish, and coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system. 8. Over 86,000 Phase II Gulf striped bass were marked with sequential coded wire tags and stocked in Lake Seminole and the Apalachicola River. Post-stocking evaluations were conducted at 31 sites. 9. Drafted updates to Apalachicola-Chattahoochee-Flint Striped Bass Restoration and Evaluation Five-Year Plan with partners. 10. Fishery surveys were conducted on Tyndall Air Force Base and St. Marks and St. Vincent National Wildlife Refuges. 11. Habitat evaluations and population surveys were completed at 153 Okaloosa darter stream sites. 12. Aquatic insect biomonitoring and identification of over 39,000 individual aquatic macroinvertebrates was completed and provided to Eglin Air Force Base. 13. Ten years of fishery data from Okefenokee and Banks Lake National Wildlife Refuges was analyzed with recommendations incorporated into the refuge Comprehensive Conservation Plan. 14. A draft mussel sampling protocol was tested in wadeable streams in northwest Florida and southwest Georgia. 15. Implemented recovery plan and candidate conservation actions for 14 listed and candidate freshwater mussels in the Northeast Gulf Watersheds. 16. Worked with partners in developing the Spring Creek Watershed Partnership in the Flint River basin, Georgia. 17. Multiple stream restoration and watershed management projects were initiated or completed. A total of 6.8 stream miles were restored for stream fishes, along with 56.4 miles of coastline were enhanced for sea turtle lighting. A total of 135 acres of wetlands and 58 acres of understory habitat were restored. 18. Multiple outreach projects were completed to detail aquatic resources conservation needs and opportunities. Participated in National Fishing Week event, BASS ProShops event, several festivals, and school outreach.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Die Tagung setzte den während der vorigen Jahrestagung zu beobachtenden Kurs einer Schwerpunktverlagerung generell fort. Diese ist durch die stärkere Berücksichtigung des Vorsorgeansatzes im Fischereimanagement auf der Grundlage wissenschaftlicher Empfehlungen des ACFM (Management-Komitee für Fischerei) des ICES gekennzeichnet. Damit traten die in der Vergangenheit fischereipolitisch dominierten nationalen Managementinteressen weitestgehend in den Hintergrund und trugen somit zu einer sachlichen Tagungsatmosphäre bei. Wichtigste Tagungsthemen waren die Ausnutzung der nationalen Quoten für 1997 und 1998 (1. Halbjahr), die Festlegung der zulässigen Gesamtfangmengen (TAC) für die internationalen Fischereien 1999, aber auch Strategien zur Nutzung der lebenden Ressourcen der Ostsee unter den Bedingungen des Vorsorgeansatzes im Fischereimanagement. An den Beratungen nahmen Ländervertreter und Experten Estlands, der EU, Lettlands, Polens und der Russischen Föderation sowie Beobachter des ICES (Internationaler Rat für Meeresforschung) und der HELCOM (Helsinki-Kommission) teil.