34 resultados para Retinal Vessels

em Aquatic Commons


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Increased boating activities and new waterfront developments have contributed an estimated 3,000 dismantled, abandoned, junked, wrecked, derelict vessels to Florida coastal waters. This report outlines a method of siting and prioritizing derelict vessel removal using the Florida Keys as a test area. The data base was information on 240 vessels, obtained from Florida Marine Patrol files. Vessel location was plotted on 1:250,000 regional and 1:5,000 and 1:12,000 site maps. Type of vessel, length, hull material, engine, fuel tanks, overall condition, afloat and submerged characteristics, and accessibility, were used to derive parametric site indices of removal priority and removal difficulty. Results indicate 59 top priority cases which should be the focus of immediate clean up efforts in the Florida Keys. Half of these cases are rated low to moderate in removal difficulty; the remainder are difficult to remove. Removal difficulty is a surrogate for removal cost: low difficulty -low cost, high difficulty - high cost. The rating scheme offers coastal planners options of focusing removal operations either on (1) specific areas with clusters of high priority derelict vessels or on (2) selected targeted derelicts at various, specific locations. (PDF has 59 pages.)

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ENGLISH: Since the inception of the Inter-American Tropical Tuna Commission in 1950, one of the primary tasks of its scientific staff has been the collection and analysis of the statistics of total catch, effort expended in obtaining this catch, and the apparent abundance of yellowfin tuna (Neothunnus macropterus) and the skipjack tuna (Katsuwonus pelamis) in the Eastern Pacific Ocean. A concentrated effort by the staff during 1951 and 1952 resulted in the compilation of a series of historical data on the catch and catch-per-effort of tropical tunas for the years 1934-1950, and in the establishment of a detailed logbook system to monitor the current activities of the tuna fleets. Schaefer (1953) and Shimada and Schaefer (1956) have reviewed in detail the methods of collection and analysis of these data. Further studies, based on these and subsequently collected records, are contained in publications by Schaefer (1957), Shimada (1958), Alverson (1959, 1960), Griffiths (1960) and Calkins (1961). SPANISH: Desde que la Comisión Interamericana del Atún Tropical comenzó sus funciones en 1950, entre las más importantes tareas de su personal científico incluyó la recolección y análisis de las estadísticas de la captura total, del esfuerzo empleado en obtener esta captura y de la abundancia aparente de los atunes aleta amarilla (Neothunnus macropterus) y barriletes (Katsutvonus pelamis) en el Océano Pacífico Oriental. El concentrado esfuerzo del personal científico de la Comisión durante 1951 y 1952 dió como resultado la compilación de una serie de datos históricos sobre la captura de atunes tropicales y sobre la captura según el esfuerzo durante los años 1934 a 1950, así como el establecimiento de un sistema detallado de registro de las anotaciones en los cuadernos de bitácora para vigilar las actividades diarias de las flotas atuneras. Schaefer (1953) y Shimada y Schaefer (1956) han expuesto detalladamente los métodos de recolección y análisis de dichos datos. Otros estudios, basados en estos registros y en los recolectados posteriormente, se encuentran en las publicaciones de Schaefer (1957), Shimada (1958), Alverson (1959, 1960), Griffiths (1960) y Calkins (1961).

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During 1973-88, 3,661 marine mammals of 17 species were reported as incidental catch by U.S. fishery observers aboard foreign and joint venture trawl vessels in the U.S. Exclusive Economic Zone in the North Pacific Ocean and the Bering Sea. Northern sea lions (Eumetopias jubatus) accounted for 90% of the reported incidental mortality in the Gulf of Alaska and eastern Bering Sea. Nearly half of these sea lions were taken in trawl nets in the Shelikof Strait, Alaska, joint venture fishery during 1982-84. However, high incidental mortality rates (>25 sea lions per 10,000 metric tons of groundfish catch) also occurred in the foreign fisheries near Kodiak Island and in the Aleutian Islands area in earlier years. Estimated annual mortality of incidentally caught northern sea lions in Alaska declined from 1,000 to 2,000 animals per year during the early 1970s and 1982 to fewer than 100 animals in 1988. In the Bering Sea most sea lions incidentally caught were males, while in the Gulf of Alaska females were more frequently caught. Females may also have been dominant in the incidental catch of sea lions in the Aleutian Islands area, but age and sex composition data are limited. Incidental mortality of adult female sea lions by foreign trawl fisheries in these areas could have partially contributed to the reported declines in northern sea lion populations in Alaska during the 1970s, but it cannot alone account for the present decline in population size. (PDF file contains 64 pages.)

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The use of self-contained, low-maintenance sensor systems installed on commercial vessels is becoming an important monitoring and scientific tool in many regions around the world. These systems integrate data from meteorological and water quality sensors with GPS data into a data stream that is automatically transferred from ship to shore. To begin linking some of this developing expertise, the Alliance for Coastal Technologies (ACT) and the European Coastal and Ocean Observing Technology (ECOOT) organized a workshop on this topic in Southampton, United Kingdom, October 10-12, 2006. The participants included technology users, technology developers, and shipping representatives. They collaborated to identify sensors currently employed on integrated systems, users of this data, limitations associated with these systems, and ways to overcome these limitations. The group also identified additional technologies that could be employed on future systems and examined whether standard architectures and data protocols for integrated systems should be established. Participants at the workshop defined 17 different parameters currently being measured by integrated systems. They identified that diverse user groups utilize information from these systems from resource management agencies, such as the Environmental Protection Agency (EPA), to local tourism groups and educational organizations. Among the limitations identified were instrument compatibility and interoperability, data quality control and quality assurance, and sensor calibration andlor maintenance frequency. Standardization of these integrated systems was viewed to be both advantageous and disadvantageous; while participants believed that standardization could be beneficial on many levels, they also felt that users may be hesitant to purchase a suite of instruments from a single manufacturer; and that a "plug and play" system including sensors from multiple manufactures may be difficult to achieve. A priority recommendation and conclusion for the general integrated sensor system community was to provide vessel operators with real-time access to relevant data (e.g., ambient temperature and salinity to increase efficiency of water treatment systems and meteorological data for increased vessel safety and operating efficiency) for broader system value. Simplified data displays are also required for education and public outreach/awareness. Other key recommendations were to encourage the use of integrated sensor packages within observing systems such as 100s and EuroGOOS, identify additional customers of sensor system data, and publish results of previous work in peer-reviewed journals to increase agency and scientific awareness and confidence in the technology. Priority recommendations and conclusions for ACT entailed highlighting the value of integrated sensor systems for vessels of opportunity through articles in the popular press, and marine science. [PDF contains 28 pages]

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ENGLISH: This report presents fine-scale spatial summaries of annual catch and effort information compiled by the IATTC staff. These data summaries are presented in a graphical format, and display only information collected from purse-seine vessels fishing in the eastern Pacific Ocean (EPO) during 1965-1998. Data collected from baitboat and longline vessels fishing in the EPO are not considered in this report. Equivalent data from Japanese longline vessels fishing in the EPO are presented by Uosaki and Bayliff(1999) for 1988-1992 and by' references cited in that publication for 1956-1987. SPANISH: Este informe presenta resúmenes espaciales a escala fina de información sobre captura y esfuerzo anuales compilada por el personal de la CIAT. Se presentan los resúmenes en formato gráfico, e incluyen solamente información tomada de barcos cerqueros pescando en el Océano Pacifico oriental (OPO) durante 1965-1998. No se consideran en el informe datos provenientes de barcos de camada y palangreros que pescan en el OPO. Se presentan datos equivalentes de barcos palangreros japoneses pescando en el OPO en Uosaki y Bayliff (1999) para 1988-1992 yen las referencias citadas en dicha publicación para 1956-1987. (PDF contains 104 pages.)

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Minimizing bycatch of seabirds is a major goal of the U.S. National Marine Fisheries Service. In Alaska waters, the bycatch (i.e., inadvertent catches) of seabirds has been an incidental result of demersal groundfish longline fishery operations. Notably, the endangered short-tailed albatross (Phoebastria albatrus) has been taken in this groundfish fishery. Bycatch rates of seabirds from individual vessels may be of particular interest because vessels with high bycatch rates may not be functioning effectively with seabird avoidance gears, and there may be a need for suggestions on how to use these avoidance gears more effectively. Therefore, bycatch estimates are usually made on an individual vessel basis and then summed to obtain the total estimate for the entire fleet.

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The catches of three longliners, including two recently converted small artisanal vessels and one large leased foreign longliner, were compared to provide some indication of the feasibility of transferring new longline technology to small vessels in the northeastern Brazilian pelagic longline fishery. Comparisons of catches between the two recently converted vessels operating across the same spatial and temporal scales showed no significant differences for the main target species, providing evidence to suggest that adoption of the technology was rapid and straightforward. A comparison of relative catch rates between one of the recently converted small longliners and the leased longliner across the same temporal scale, but in different areas, showed that while there were significant differences detected for some species, contributing to a significant reduction in total CPUE, the relative abundance of commercially important species within the operational range of the smaller vessels was sufficient for economically viable catches. The results showed that the net financial profit from the artisanal longliner was almost 10 times greater than that derived from existing fishing methods. The inclusion of some artisanal vessels in this fishery may help address the social and economic problems currently faced by fi

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Logbook set and trip summary data (containing catch and cost information, respectively) collected by NOAA’s National Marine Fisheries Service (NMFS) were analyzed for U.S. pelagic longline vessels that participated in Atlantic fisheries in 1996. These data were augmented with vessel information from the U.S. Coast Guard. Mean fish weights and ex-vessel prices from NMFS observers and licensed seafood dealers, respectively, were used to estimate gross revenues. Comparisons revealed that net returns varied substantially by vessel size and fishing behavior (i.e. sets per trip, fishing location, season, and swordfish targeting). While the calculated economic effects of proposed regulations will depend on the descriptive statistic chosen for analysis, which itself depends on the type of analysis being conducted, results show that considering heterogeneity within this fleet can have a significant effect on predicted economic consequences.

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Shrimp fishermen trawling in the Gulf of Mexico and south Atlantic inadvertently capture and kill sea turtles which are classified as endangered species. Recent legislation requires the use of a Turtle Excluder Device(TED) which, when in place in the shrimp trawl, reduces sea turtle mortality. The impact of the TED on shrimp production is not known. This intermediate analysis of the TED regulations using an annual firm level simulation model indicated that the average Texas shrimp vessel had a low probability of being an economic success before regulations were enacted. An assumption that the TED regulations resulted in decreased production aggravated this condition and the change in Ending Net Worth and Net Present Value of Ending Net Worth before and after a TED was placed in the net was significant at the 5 percent level. However, the difference in the Internal Rate of Return for the TED and non-TED simulations was not significant unless the TED caused a substantial change in catch. This analysis did not allow for interactions between the fishermen in the shrimp industry, an assumption which could significantly alter the impact of TED use on the catch and earnings of the individual shrimp vessel.

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This handbook provides detailed information for a wide range of legal instruments relevant to fisheries and fishworkers. It covers 114 legal instruments, categorized into the following seven themes: Theme I. Human Rights, Food Security, Women and Development. Theme II. Environment and Sustainable Development. Theme III. Oceans and Fisheries Management. Theme IV. Environmental Pollution Theme V. Fishing Vessels and Safety at Sea Theme VI. Labour Theme VII. Trade The handbook also includes the working of the instruments (decision-making bodies, monitoring and implementation agencies, periodicity of meetings, rules for participation in meetings of the decision-making bodies and implementation agencies for States and non-governmental organizations), regional instrument and agencies. Apart from being a ready reckoner to the instruments, it highlights the important sections of relevance to fisheries or small-scale fisheries and fishworkers. The companion CD-ROM provides the full texts of the instruments in a searchable database. The handbook will be useful for fishworker and non-governmental organizations, and also for researchers and others interested in fisheries issues.