70 resultados para Pellegatta, Omar, 1925-2000


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fish larvae surveys provide information on the species composition in an area of investigation and leads to a better understanding of the entire fish community. Since 2000 every year in April/May an ichthyoplankton survey in ICES-Subdivision 22 and 24 has been performed to sample the plankton community in the western Baltic Sea. One objective was to acquire indicators of possible changes in the natural structures of the fish community. The time series derived from the Bongo-Net samples is too short to show a trend in larval densities. Up to now samples in the western Baltic Sea yielded only low mean densities. According to the reproductive biology the fish species were divided in three major groups: -Fish species with a long developmental phase in the plankton community -Small short living species with benthic eggs and a reduced planktonic phase -Guests without local spawning populations Species were identified, which were absent in the plankton of the western Baltic Sea in the 1960s and 1970s.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ichthyoplankton provides information on the species com-position in an area of investigation and leads to a better understanding of the entire fish community. Every year since 1993 May/June (from 2000 in April/May) an ichthyoplankton survey in ICES Subdivision 22 and 24 has been done to sample the plankton community in the western Baltic Sea. One objective was to acquire indicators of possible changes in the natural structures of the fish com-munity. The time series derived from the Bongo-Net samples is too short to show a trend in larval densities. Up to now samples in the western Baltic Sea yielded only low mean densities. According to the reproductive biology the fish species were divided in three major groups: •Fish species with a long developmental phase in the plankton community •Small short lived species with benthic eggs and a reduced planktonic phase •Guests without local spawning populations. Species were identified, which were absent in the plankton of the western Baltic Sea in the 1960s and 1970s.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The German shrimp fisheries land different types of pro-duce. Besides cooked shrimp for human consumption small (undersized), raw shrimp (industrial shrimp) are landed regionally in the second half of each year for animal feedstuff purposes. They are dried in special plants and form sellable secession from sieving processes aboard shrimping vessels. Grading the cooked shrimp ashore gives the non-marketable fraction of too small shrimp, which is not meant for shelling. That fraction is produced all year alongside landings of shrimp and is used for feed-stuff as well. Both extra fractions are listed in the official statistics since 2000 for the first time. That year industrial shrimp made up 6 % of the total landings while the non-marketable, small cooked shrimp summed up to 7 %, respectively. Though being essential for specialised animal feeds they are commercially of very little value, making up to hardly 2 ‰ of the total turnover of the German shrimp fisheries.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

During the autumn session of the ICES Advisory Committee for Fisheries Management (ACFM) the stock of the Arctic, Northern and Southern Shelf, North Sea and Skagerrak have been analysed and assessed, as well as the mackerel and horse mackerel, sardine, anchovy and Pandalus, eel and harp and hooded seals. For a number of stocks ICES recommends a reduction in fishing mortality. Moreover, ICES recommends for many stocks to establish recovery and management plans, to safe guarda continuous development of the stocks towards safe biological limits.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The spring session of ACFM gave advice for a number of stocks in the North Atlantic, North Sea and Baltic. The present assessment of the situation is given here for stocks of higher importance for the German fishery. These are: Blue Whiting: the stock is still relatively high, this, however, will not last very long, due to too intense fishing. Cod in Kattegat: stock is outside safe biological limits. No immediate recovery in sight. Cod in 22–24 (Baltic): stock is inside save biological limits. F, however, is above the recommendation of the IBSFC. Greenland Halibut: state of the stock not quite clear. The present fishing intensity seems to be sustainable. Herring (Atlanto- scandian, Norwegian spring spawner): stock is within safe biological limits, weak recruitment of the recent years will lead to a reduction of biomass. Herring: for Baltic spring spawner in 22–24 and IIIa still no increasing tendency detectable. North Sea Herring: further increasing tendency, with 900 000 t over B lim, good recruitment. Herring in VIa: stable. Redfish: generally decreasing tendency observed, a reduction of the fishery is recommended. Signs of recovery, however, visible for some units

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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 of this year’s herring larvae survey indicate a weak year-class 2000.

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:

This report represents the key output of a training workshop hosted by Lake Victoria Fisheries Research Project (LVFRP) for researchers from each of the riparian countries fisheries research institutes. The workshop aimed to train the researchers in participatory research techniques which they could use to undertake a study of community-based institutions and organizations which could potentially be involved in fisheries co-management. A central focus of the workshop was a study to identify the community-based organizations and institutions, which operated at Kiumba beach, and this study is reported here. Separate reports, which include operated at Kiumba beach and this study is reported here. Separate reports, which include details of the training process and the participatory methods used, are available (Sarch 1995, 2000). The report centers on the information generated from the participatory pilot study conducted by the workshop participants and the community at Kiumba Beach over the course of a week in March 2000. Ranges of participatory research techniques were used and the discussion and diagrams, which resulted from them, form the basis of this report. The workshop participants undertook a preliminary analysis of these findings and this has been synthesized at the end of this report. (PDF contains 55 pages)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article outlines the development of freshwater science between 1900 and 2000 and in particular traces British contributions, both to a deepened knowledge of specifics and to their interrelation as environmental and ecological science. The author provides a selected bibliography of important publications relevant to the topic of the article.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ihale is a large landing site lying approximately 65 km. from Mwanza along the main Mwanza-Musoma highway. Ihale Beach was selected as a potential candidate for the 3-beaches study because of its proximity to Mwanza, and hence suitability for frequent monitoring; and because it is served by a road accessible during the rainy seasons. As with the first training Participatory Rural Appraisal (PRA) on Kiumba Beach on Kenya's Rusinga Island, the objectives with this PRA were as follows: (a) To identify and understand Ihale's community-based organizations and institutions which have a role in the lake's fishery. (b) To consider the key issues which arise from this study for the involvement of communities and community-based organizations and/or institutions such as those at Ihale Beach, in the co-management of Lake Victoria's fishery.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document contains the findings of the second Participatory Rural Appraisal (PRA) carried out under the LVFRP. Its principal objectives were to develop base-line information on a Ugandan beach for the 3-beaches survey of the LVFRP.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document contains the findings of the third Participatory Rural Appraisal (PRA) carried out on Obenge Beach in Kenya, from the 23rd to the 26th of June 2000, under the LVFRP. Its principal objectives were to develop base-line information on a Kenyan beach for the 3-beaches survey of the LVFRP.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This document contains the findings of the fourth Participatory Rural Appraisal (PRA) carried out under the LVFRP. Its principal objectives were to develop base-line information on a Ugandan beach for the 3-beaches survey of the LVFRP.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper comprises part of the so-called "3-beaches Survey" of the LVFRP. In Tanzania, this study has developed to examine two landing sites (Mwasonge and Ihale), and to chart the progress of the newly established Beach Management Units (BMU) at each beach, comparing one BMU against the other. The over-arching objective of this survey was to develop an understanding of the context in which Mwasonge's fishery exists. The study does so by examining the community's history, culture and beliefs, various other socio-cultural factors, their resources, society and economy, wealth and the community's perceptions of wealth. Importantly, the survey examines the community's institutions and its perceptions of fishing rules and changes within the fishery. All of these facets of community life are examined with the use of participatory Rural Appraisal tools, and the images that the study generated are reproduced herein.