194 resultados para Armored vessels.
Resumo:
A widespread belief among fishermen that sidetrawlers show a better selectivity than sterntrawlers was investigated in a comparative fishing exercise in the Baltic. In contrary to earlier observations during this experiment in May no essential differences with regard to the selectivity of the trawls used could be found for both types of fishing vessels. Possible explanations for the result are discussed.
Resumo:
Seven research vessels of ICES member countries participated, in order to investigate the strength of incoming yearclasses of commereially most important species. Germany took part in the investigations by R.V. "Walther Herwig III" from January 23 to February 24. Indices of a total of 330 stations indicate a positive development of the stocks of haddock, Norway pout and sprat whereas indices for cod, whiting, and herring remain in the mean of the last years. Water temperatures were up to 1 K above the longterm mean. Salinities were measured regionally both above and below mean values up to 1 0/00.
Resumo:
In order to determine the abundance of incoming year classes of both mackerel and horse mackerel a couple of research vessels in the frame of ICES investigats waters west of the British Isles, the Gulf of Biscay and areas west of the Iberian Peninsula in the first half of each third year. In 1995, Germany took place in these investigations with R.V. "Walther Herwig III" from March 23 to April 18. A total of 100 plankton stations were made using a Gulf - III - Sampier between Fastnet Rock and the Gironde estuary. In addition, 87 fishing stations were occupied by a GOV net. Though fish indications were not fished on purpose large amounts of especially horse mackerel and mackerel were gained in the half hour tows. Besides, boarfish (Capros aper L.), blue whiting, and sprat were found in considerable quantities and numbers in some areas. The hydrographc situation was as expected: The development of a surfaee thermocline created by radiation indieates the collapse of the vertically homogeneous situation of the winter period.
Resumo:
The new German R.V. "Walther Herwig III" joined the International North Sea Bottom Trawl Survey (IBTS) coordinated in the frame or ICES from February 18 to March 22 1994. A total of 354 valid half hour tows were made by seven research vessels from the different ICES members in order to determine the strength of incoming year classes of commercially most important fish species. Preliminary index figures for the stocks under observation of all participating vessels show that only the North Sea sprat stock developed a substantial year class in 1993. In addition, hydrographic data were collected during the survey. These data show the temperatures and salinities of the northern and central North Sea in most parts beneath the mean values during the period under investigation.
Resumo:
A decline in the abundance of blackback flounders, together with the withdrawal of vessels from this fishery, has resulted in a lowered catch in recent years compared to the peak period 1928 through 1931. Data obtained from U. S. Fish and Wildlife Service Hatchery catch records and from fishermen's log book records show a drop in abundance of 63 per cent from the early 1930's to the present in the Boothbay Harbor region and of 31 to 40 per cent in the area south of Cape Cod. Information on the early life history and distribution of young blackback flounders and the size and age composition and distribution of fish subject to the commercial and sport fisheries indicates that the young are the product of local spawning and that the sport and commercial fisheries draw on a resident stock of primarily adult fish.
Resumo:
It has long been known that tunas frequently associate with floating objects, such as trees washed out to sea during periods of heavy rainfall, and fishermen have taken advantage of this behavior to facilitate the capture of fish. In some coastal areas, such as the Philippines, artisanal fishermen construct anchored fish-aggregating devices (FADs) to attract fish. More recently, large numbers of free-floating FADs have been constructed for deployment by large purse seiners on the high seas. The FADs often can be interrogated by the seiner and located at great distances using radio telemetry and/or GPS (Global Positioning System) technologies. In some cases a fleet of fishing vessels has a tender vessel which deploys and maintains the FADs, and notifies the fishing vessels when fish are seen around them. This workshop was convened by the Inter-American Tropical Tuna Commission and sponsored by Bumble Bee Seafoods, Inc., for the purpose of bringing together scientists and fishermen who have studied the association of tunas with floating objects. Special efforts were made to get participants from all the areas in which tunas associated with floating objects are the targets of fisheries. Thus the "regional review papers" include contributions for the eastern Atlantic, the southern Caribbean Sea, the Indian Ocean, and the eastern and western Pacific Oceans. Many of these reviews and other contributed papers are published in this proceedings volume. Other papers discussed in the workshop were published elsewhere; these papers are cited in the list of background documents in the Report of the Workshop.
Resumo:
Along with consumption shrimp, brown shrimp fisheries also land some shrimp too small for human consumption which are sieved out on land and have to be degenerated (“crushed shrimp”). This share is recorded in German official statistics besides a third fraction called “industrial shrimp”. In view of the MSC certification processes, sustainable fishing and the fishermen’s voluntary obligation to - in future - limit the shares of “crushed shrimp”, landings data from 2010 have been analysed. Depending on seasons the goal of less than 20% of “crushed shrimp” in German landings was not met in several months in 2010, especially in August, when more than 40% of the landings contained more than the proposed amount. The processing procedures aboard the vessels are shortly discussed and the proposal is made to rather increase net selectivity than use wider sieves for the cooked fraction before landing. Cooking and processing small and later rejected shrimp is an uneconomic action. Reducing the share of “crushed shrimp” serves the idea of sustainable use of shrimp stocks as well as of sound economics.
Resumo:
Large numbers of fishing vessels operating from ports in Latin America participate in surface longline fisheries in the eastern Pacific Ocean (EPO), and several species of sea turtles inhabit the grounds where these fleets operate. The endangered status of several sea turtle species, and the success of circle hooks (‘treatment’ hooks) in reducing turtle hookings in other ocean areas, as compared to J-hooks and Japanese-style tuna hooks (‘control’ hooks), prompted the initiation of a hook exchange program on the west coast of Latin America, the Eastern Pacific Regional Sea Turtle Program (EPRSTP)1. One of the goals of the EPRSTP is to determine if circle hooks would be effective at reducing turtle bycatch in artisanal fisheries of the EPO without significantly reducing the catch of marketable fish species. Participating fishers were provided with circle hooks at no cost and asked to replace the J/Japanese-style tuna hooks on their longlines with circle hooks in an alternating manner. Data collected by the EPRSTP show differences in longline gear and operational characteristics within and among countries. These aspects of the data, in addition to difficulties encountered with implementation of the alternating-hook design, pose challenges for analysis of these data.
Resumo:
From 1979 to 1983, several surveys were carried out with research and fishing vessels at Sofala Bank in Mozambique. Their main objective was the assessment of shallow water prawn stocks, as this resource is of great economic importance for the country. A summary of the conclusions of these surveys regarding the species Penaeus indicus is presented. During the rainy season the species occurs closer to the shore than during the dry season. Estimates of biomass are very variable. The spawning peak seems to occur at the beginning of the rainy season (September-October). The spawning areas are located very close to the shore in the northern part of Sofala Bank and South of 17 degree 10'S in the 15-25 m depth interval.
Resumo:
The most important fisheries of Maputo Bay (Mozambique) are the gill netting of the Hilsa kelee and the trawling of the shrimps Penaeus indicus and Metapenaeus monoceros . Data of capture and yields are presented and the number of artisanal fishing boats and semi-industrial fishing vessels is given.
Resumo:
This work reflects the activities of line and trap fishing in Southern Mozambique in 2000. The catch in line fishing has been estimated at 441 mt, according to the DNAP records. The same sources indicated that 1767 days were spent at sea and the estimated catch rate was 250 Kg per boaticlay. Most of the line fishing effort shifted away from Maputo and moved to Inhambane region. The monthly analysis of fishing vessels, stricter controls over catch and effort data submission, development of long-term research programme and the continuation of the on board sampling to improve the data collection are the recommendation for line fishing. The catch of trap vessels increases from 30mt in 1997 to 172 mt in 2000, during which the total number of traps increased from 25 to 300. During this time the number of fishing days has remained relatively constant, as well the soak time. These data sets are thus not compatible with each other, reflecting an increase in daily catch from 243 Kg to 791 kg. The species composition is mainly dominated by P. coeruleopunctatus, C. puniceus, C. nufar and E. andersoni.
Resumo:
The method developed by Robson (1966) is used to standardize fishing effort of Côte d'Ivoire trawlers whose size and power are very different. This method also allows the estimation of the relative abundances in the different fishing areas. The results obtained using 10 years data show that the entire Ivorian continental shelf can be considered as a single fishery unit. The relative fishing power of vessels is well correlated with gross tonnage, brake horse power and length of the vessel. The obsolescence of the trawlers affects their fishing power.
Resumo:
The report provides an account of the activities carried out by the Lake Kariba Fisheries Research Institute during the year 1993 under the following headings: Institute finances; Staffing and staff training; Staff housing; Infrastructure and institute expansion; Vehicles and vessels; and, Fisheries and fishery management. Individual reports regarding the various project activities conducted during the year are also included.
Resumo:
The report provides an account of the activities carried out by the Lake Kariba Fisheries Research Institute during the year 1994 under the following headings: Institute finances; Staffing and staff training; Staff housing; Infrastructure and institute expansion; Vehicles and vessels; and, Fisheries and fishery management. Individual reports regarding the various project activities conducted during the year are also included.
Resumo:
The report provides an account of the activities of the Lake Kariba Fisheries Research Institute of Zimbabwe during the period July 1997 to December 1998. It is presented under the following major headings: 1) Introduction; 2) Institute finances; 3) Staffing and staff training; 4) Infrastructure; 5) Vehicles and vessels; 6) Fisheries management -- kapenta management, inshore fisheries management, law enforcement; 7) Kariba Lakeshore Combination Masterplan; 8) Joint protocol; 9) Research work; and, 10) Publications and presentations.