Die Fangmengen an Nordseegarnelen und fischereilicher Aufwand im europäischen Vergleich - Langzeitserien und saisonale Übersicht

Among other tasks the “Working Group on Crangon Fisheries and Life Cycle” of the “International Council for the Exploration of the Sea” collects data on landings and effort in the North Sea brown shrimp fisheries by country. Landings per unit effort data are calculated and all are compared on basis of long-term series as well as on seasonal basis. The development for each country is described and compared for the year 2001 to the ten-year average from 1992 to 2001 were possible, as some data are missing especially for the Netherlands. While the Dutch and British fleets increased their landings substantially in 2001 compared to the previous years, Danish,German and Belgian fishermen had reduced landings. There are regional differences in fishing pattern between the countries, especially Denmark versus the rest of Europe. Effort measures remain incomparable between the countries, and fluctuations in landings per unit effort data seem to be in a normal biological range, giving no reason for concern at present for the situation of brown shrimp stocks in the North Sea. An improvement of the data basis is required and possibly achievable by the EU logbook system being in force for brown shrimp fisheries as well.

Decision support systems optimising effluent release in sub tropical estuarine environment - An Australian case study

Gold Coast Water is responsible for the management of the water and wastewater assets of the City of the Gold Coast on Australia’s east coast. Treated wastewater is released at the Gold Coast Seaway on an outgoing tide in order for the plume to be dispersed before the tide changes and renters the Broadwater estuary. Rapid population growth over the past decade has placed increasing demands on the receiving waters for the release of the City’s effluent. The Seaway SmartRelease Project is designed to optimise the release of the effluent from the City’s main wastewater treatment plant in order to minimise the impact of the estuarine water quality and maximise the cost efficiency of pumping. In order to do this an optimisation study that involves water quality monitoring, numerical modelling and a web based decision support system was conducted. An intensive monitoring campaign provided information on water levels, currents, winds, waves, nutrients and bacterial levels within the Broadwater. These data were then used to calibrate and verify numerical models using the MIKE by DHI suite of software. The decision support system then collects continually measured data such as water levels, interacts with the WWTP SCADA system, runs the models in forecast mode and provides the optimal time window to release the required amount of effluent from the WWTP. The City’s increasing population means that the length of time available for releasing the water with minimal impact may be exceeded within 5 years. Optimising the release of the treated water through monitoring, modelling and a decision support system has been an effective way of demonstrating the limited environmental impact of the expected short term increase in effluent disposal procedures. (PDF contains 5 pages)

Eléments nutritifs et production primaire dans les lagunes du Côte d'Ivoire : cycle annuel

This paper collects most of the information gathered between October 1974 and July 1976 within the framework of a research program concerning the hydrobioclimate of ivorian lagoons and especially the Ebrié lagoon. Monthly surveys concerning the latter were carried out during 1975. The following parameters - and their vertical distribution wherever it had a meaning - were systematically gathered in a system of fifty-five stations: Transparency (Secchi), Temperature, Salinity, Chlorophylla, Dissolved oxygen, phosphate, nitrate, nitrite. These data provide an outline of the annual cycle of nutrients and primary production of the Ivoirian lagoons

Bibliographie des lagunes et du littoral de Côte d'Ivoire (Afrique de l'Ouest)

The present bibliography collects references on lagoon and coastal environments in Côte d'Ivoire. It is mainly based on: - the draft bibliography prepared by Charles-Dominique and Durand in 1979, edited in the Archives Scientifiques du Centre de Recherches Océanographiques d'Abidjan (vol. 5 no. 2); - the synthesis on the marine environment, published in 1993 (LeLoeuff, Marchal and Amon-Kothias editors); - and the synthesis on the lagoon environment, published in 1994 (Durand, Dufour, Guiral and Zabi editors). In spite of a careful check of the available documents, it is more than possible that references are lacking or erroneous. That's why this bibliography is still a draft, and the author will be glad to receive complements and/or corrections from lectors. After these contributions, a more comprehensive version will be proposed. Remarks can be sent to this e-mail: arfi@ortsom.orstom.fr or to the postal address.

The fishery for California market squid (Loligo opalescens) (Cephalopoda: Myopsida), from 1981 through 2003

The California market squid (Loligo opalescens) has been harvested since the 1860s and it has become the largest fishery in California in terms of tonnage and dollars since 1993. The fishery began in Monterey Bay and then shifted to southern California, where effort has increased steadily since 1983. The California Department of Fish and Game (CDFG) collects information on landings of squid, including tonnage, location, and date of capture. We compared landings data gathered by CDFG with sea surface temperature (SST), upwelling index (UI), the southern oscillation index (SOI), and their respective anomalies. We found that the squid fishery in Monterey Bay expends twice the effort of that in southern California. Squid landings decreased substantially following large El Niño events in 1982−83 and 1997−98, but not following the smaller El Niño events of 1987 and 1992. Spectral analysis revealed autocorrelation at annual and 4.5-year intervals (similar to the time period between El Niño cycles). But this analysis did not reveal any fortnightly or monthly spawning peaks, thus squid spawning did not correlate with tides. A paralarvae density index (PDI) for February correlated well with catch per unit of effort (CPUE) for the following November recruitment of adults to the spawning grounds. This stock– recruitment analysis was significant for 2000−03 (CPUE=8.42+0.41PDI, adjusted coefficient of determination, r2=0.978, P=0.0074). Surveys of squid paralarvae explained 97.8% of the variance for catches of adult squid nine months later. The regression of CPUE on PDI could be used to manage the fishery. Catch limits for the fishery could be set on the basis of paralarvae abundance surveyed nine months earlier.

The Black Clam, Villorita cyprinoides, Fishery in the State of Kerala, India

The black clam, Villorita cyprinoides, is the most important clam species landed in India. The State of Kerala has been, by far, the leading producer of the species. Nearly all the landings, about 25,000 tons (t)/year are harvested in Vembanad Lake, the largest estuary, 96 km (54 mi) long, on the west coast of India. Nearly 4,000 fishermen harvest the black clams year-round. They harvest most by hand while diving in waters from 2.1–2.7 m (7–9 ft) deep. Each collects 150–200 kg (3–5 bushels)/day. Upon returning from the harvesting beds, the fishermen and their families cook the clams and separate their meats from their shells using simple sieves. Fishermen’s wives sell the meats within their local villages and save some for their families to eat. The shells are sold through organized fishermen societies to various industries. A substantial quantity of sub-fossil black clam shells lies buried from 22–50 cm (9–20 in) beneath the lake sediments. They are dredged in a controlled manner and sold to the same industries. The stocks of black clams seem to be declining slowly in the southern part of the lake because the water has been getting fresher, but they are not declining in the northern half. A likely threat to the landings may be a lack of fishermen in the future.

Initial formation of the U.S. Geological Survey hydroclimatic data network [abstract]

EXTRACT (SEE PDF FOR FULL ABSTRACT): The U.S. Geological Survey is working to define a hydroclimatic data network. The Geological Survey collects stream discharge data at more than 7000 sites throughout the United States. Many of these stations are operated to supply information about specific activities such as flood control, irrigation projects, or hydropower generation. As a beginning, the Geological Survey will attempt to identify stations that represent natural streamflow. Several lists of stations representing "natural" streamflow have been complied in the past. While there is some overlap among these lists, a consistent compilation is preferred. The present effort is to produce one list identifying those stations having periods of record which would be suitable for mesoscale climatic analyses.

Northeast Fisheries Observer Program manual, 2013

The National Marine Fisheries Service (NMFS) Northeast Fisheries Science Center (NEFSC) Fisheries Sampling Branch (FSB) collects, maintains, and distributes data for scientific and management purposes in the northwest Atlantic Ocean. FSB manages three separate but related observer programs: the Northeast Fisheries Observer Program (NEFOP), the Industry Funded Scallop (IFS) Observer Program, and the At Sea Monitoring (ASM) Program. For the purposes of this manual, “observers” refers to any observer/monitor working for the FSB. In 2011, FSB trained and deployed over 200 observers, provided coverage on a variety of fisheries, and completed over 15,000 sea days. Observed trips are required under many of the region's fishery management plans, and for some fisheries by other federal laws and authorities such as Amendment 16 and Framework 44, Magnuson-Stevens Fishery Conservation and Management Act, Marine Mammal Protection Act, the Endangered Species Act, the and the Sustainable Fisheries Act. The purpose of this guide is to provide FSB observers, as well as end users of NEFSC Observer Program data, with a detailed description of each data field collected. In addition to this manual, the NEFSC Observer Program Biological Sampling and Catch Estimation Manual provides summaries and tables intended to enable observers to quickly determine the correct sampling protocols and methods while at sea. This manual represents a revision of the data forms, collection procedures, and protocols described in the 1996 NEFSC Observer Program Manual. For documentation of other changes see Documentation of changes made to the NEFSC Fisheries Observer Program Manual, 2013.