964 resultados para marine life


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This report considers the development of environmental quality standards (EQSs) for the salmonid fishery, cyprinid fishery, migratory fishery, commercial harvesting of marine fish for public consumption and commercial harvesting of shellfish for public consumption uses of controlled surface waters. Previous reports have been used to identify those parameters necessary for the maintenance of these five uses. Each water use is considered in a separate section within which identified parameters are discussed and standards proposed, a summary of the proposed standards is presented at the beginning of the relevant section. For salmonid, cyprinid and migratory fisheries, EQSs for substances in water have been proposed for the protection of these fisheries. For the commercial harvesting of marine fish and shellfish for public consumption uses 'Warning Levels' of substances in waters have been proposed. These 'Warning Levels' have been proposed by considering data on bioaccumulation and food standards and aim to prevent acceptable intake values and concentrations in fish/shellfish flesh exceeding statutory or recommended levels. For the commercial harvesting of marine fish for public consumption it has been concluded that the current EQSs for most List II substances for the protection of salt water life should be adequately stringent to protect this use, however for the commercial harvesting of shellfish for public consumption, these List II EQSs do not appear adequate to protect this use and more stringent 'Warning Levels' have been proposed. For all five uses considered in this report there has been found to be limited information on a number of the parameters considered and in general for indigenous species, this has been found to be especially so when considering migratory fisheries and the commercial harvesting of marine fish and shellfish.

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Settled juvenile blue rockfish (Sebastes mystinus) were collected from two kelp beds approximately 335 km apart off Mendocino in northern California and Monterey in central California. A total of 112 rockfish were collected from both sites over 5 years (1993, 1994, 2001, 2002, and 2003). Total age, settlement date, age at settlement, and birth date were determined from otolith microstructure. Fish off Mendocino settled mostly in June and fish off Monterey settled mostly in May (average difference in settlement=23 days). Although the difference in the timing of settlement followed this same pattern for both areas over the five years, settlement occurred later in 2002 and 2003 than in the prior years of sampling. The difference in the timing of settlement was due primarily to differences in birth dates for the two areas. The time of settlement was positively related to upwelling and negatively related to sea level anomaly for most of the months before settlement. Knowledge of the timing of settlement has implications for design and placement of marine protected areas because protection of nursery grounds is frequently a major objective of these protected areas. The timing of settlement is also an important consideration in the planning of surveys of early recruits because mistimed surveys (caused by latitudinal differences in the timing of settlement) could produce biased estimates.

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Marine ecosystems compose the major source (85%) of world fisheries production (Garcia and Newton, 1997). Although only a few fish species tend to dominate fishery catches (Jennings et al., 2001), a large diversity of fishes representing varied taxonomic levels, ecological guilds, and life histories is commonly taken. Recently, 66% of global marine resources were determined to be either fully, heavily, or over-exploited (Botsford et al., 1997). Considering the current state of many fisheries, the large diversity of species taken globally, and the general lack of resources to adequately assess many stocks, it has become important to develop shortcuts that may provide methods fisheries scientists can use to determine which stocks are in danger of overexploitation and which recovery plans are appropriate when biological data are limited (Stobutzki et al., 2001).

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Sand sole, Psettichthys melanostictus, is a small but important part of the west coast groundfish fishery. It has never been assessed and there is a limited amount of biological data for the species. We provide the first estimates of age and growth for California populations and compare them with studies from other areas. We found that sand sole is a rapidly growing species which may show a strong latitudinal gradient in growth rate. We also found evidence of a recent, strong cohortrelated shift in the sex ratio of the population towards fewer females. In addition we examined data from the Washington, Oregon, and California commercial fishery to make an initial determination of population status. We found that catch per unit of effort in commercial trawls experienced a decline over time but has rebounded in recent years, except central California (the southern part of its commercial range), where the decline has not reversed.

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Since 1988 regulations have required U.S. longline fishermen to release all Atlantic white marlin, Tetrapturus albidus. By the late 1990’s, approximately 99% of Atlantic white marlin caught by U.S. recreational fishermen were released. Recent studies using PSAT technology indicate that not all released fish survive and that a minor change in hook type, 0–5° offset circle hooks rather than straight-shank “J” hooks, may have a profound effect on post release mortality. Beginning in 2004, sea turtle mitigation measures have required U.S. longline fishermen to use circle hooks. Estimates of total catch, releases, and post release mortality of Atlantic white marlin caught by U.S. recreational fishermen were made in order to evaluate the potential reduction in mortality that may be realized by requiring the use of circle hooks rather than straight-shank “J” hooks by U.S. recreational fishermen. These estimates were compared to estimates of Atlantic white marlin caught by the U.S. longline fishery

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The white shark, Carcharodon carcharias, is considered rare in the Gulf of Mexico; however, recent longline captures coupled with historical landings information suggest that the species occurs seasonally (winter-spring) within this region. We examined a total of seven adult and juvenile white sharks (185-472 em total length) captured in waters off the west coast of Florida. Commercial longline fisheries were monitored for white sharks during all months (1981-94), but this species was captured only from January to April. All white sharks were captured in continental shelf waters from 37 to 222 km off the west coast of Florida when sea surface temperatures ranged from 18.7° to 21.6°C. Depths at capture locations ranged from 20 to 164 m. Fishing gear typically used in Gulf of Mexico offshore fisheries may not be effective at capturing this species, and the apparent rarity of white sharks in this area may be, in part, a function of gear bias.

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Four recognized species of menhaden, Brevoortia spp., occur in North American marine waters: Atlantic menhaden, B. tyrannus; Gulf menhaden, B. patronus; yellowfin menhaden. B. smithi; and finescale menhaden, B. gunteri. Three of the menhaden species are known to form two hybrid types. Members of the genus range from coastal waters of Veracruz, Mex., to Nova Scotia, Can. Atlantic and Gulf menhaden are extremely abundant within their respective ranges and support extensive purse-seine reduction (to fish meal and oil) fisheries. All menhaden species are estuarine dependent through late larval and juvenile stages. Depending on species and location within the range, spawning may occur within bays and sounds to a substantial distance offshore. Menhaden are considered to be filter-feeding, planktivorous omnivores as juveniles and adults. Menhaden eggs, immature developmental stages, and adults are potential prey for a large and diverse number of predators. North American menhadens, including two hybrids, are hosts for the parasitic isopod, Olencira praegustator, and the parasitic copepod, Lemaeenicus radiatus. Although the data are quite variable, a dome-shaped Ricker function is frequently used to describe the spawner-recruitment relationship for Atlantic and Gulf menhaden. Each of these species is treated as a single stock with respect to exploitation by the purse-seine reduction fishery. Estimates of instantaneous natural (other) mortality rates are O.45 for Atlantic menhaden and 1.1 for Gulf menhaden.

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A review of the significant contributions in the peer-reviewed literature indicates that the discarding of marine fish known as bycatch remains one of the most significant problem facing fisheries managers. Bycatch has negative affects on marine biodiversity, is ripe with ethical and moral issues surrounding the waste of life from increased juvenile fish mortality, hinders commercial profitability and recreational satisfaction, increases management costs, and results in socio-cultural problems and conflicts. While appearing to have a simple conservation engineering solution, reducing or eliminating bycatch in marine fishing operations given the presently existing regulated open access management environment is demonstrated to actually be so complex that its effects can appear to be counter-intuitive. An ecosystem simulation model that explicitly incorporates the human and biological dimensions is used to evaluate proposed bycatch reduction regulations for two fishing fleets exploiting three out of seven species of fish, each with ten cohorts, in two resource areas. One of the fishing fleets is divided into two components representing commercial fishermen and recreational anglers. The seven fish species represent predator, prey, and competitor behaviors and one stock is treated as an endangered species. The results displayed in a series of figures demonstrate the potential unintended effects of simplistic management approaches and the need for a holistic and comprehensive approach to bycatch management. That is, an ecosystem model that explicitly incorporates socio-cultural and biophysical attributes into a common framework allows the magnitude and direction of behavioral responses to be predicted based on changes in governance or biophysical constraints to determine if management goals and objectives have been obtained through the use of quantitative metrics.

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The National Marine Fisheries Service (NMFS) is dedicated to the stewardship of living marine resources (LMR’s). This is accomplished through science-based conservation and management, and the promotion of healthy ecosystems. As a steward, NMFS has an obligation to conserve, protect, and manage these resources in a way that ensures their continuation as functioning components of healthy marine ecosystems, affords economic opportunities, and enhances the quality of life for the American public. In addition to its responsibilities within the U.S. Exclusive Economic Zone (EEZ), NMFS plays a supportive and advisory role in the management of LMR’s in the coastal areas under state jurisdiction and provides scientific and policy leadership in the international arena. NMFS also implements international measures for the conservation and management of LMR’s, as appropriate.NMFS receives its stewardship responsibilities under a number of Federal laws. These include the Nation’s primary fisheries law, the Magnuson Fishery Conservation and Management Act. This law was first passed in 1976, later reauthorized as the Magnuson-Stevens Fishery Conservation and Management Act in 1996, and reauthorized again on 12 January 2007 as the Magnuson-Stevens Fishery Conservation and Management Reauthorization Act (MSRA). The MSRA mandates strong action to conserve and manage fishery resources and requires NMFS to end overfishing by 2010 in all U.S. commercial and recreational fisheries, rebuild all overfished stocks, and conserve essential fish habitat.

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This report argues for greatly increased resources in terms of data collection facilities and staff to collect, process, and analyze the data, and to communicate the results, in order for NMFS to fulfill its mandate to conserve and manage marine resources. In fact, the authors of this report had great difficulty defining the "ideal" situation to which fisheries stock assessments and management should aspire. One of the primary objectives of fisheries management is to develop sustainable harvest policies that minimize the risks of overfishing both target species and associated species. This can be achieved in a wide spectrum of ways, ranging between the following two extremes. The first is to implement only simple management measures with correspondingly simple assessment demands, which will usually mean setting fishing mortality targets at relatively low levels in order to reduce the risk of unknowingly overfishing or driving ecosystems towards undesirable system states. The second is to expand existing data collection and analysis programs to provide an adequate knowledge base that can support higher fishing mortality targets while still ensuring low risk to target and associated species and ecosystems. However, defining "adequate" is difficult, especially when scientists have not even identified all marine species, and information on catches, abundances, and life histories of many target species, and most associated species, is sparse. Increasing calls from the public, stakeholders, and the scientific community to implement ecosystem-based stock assessment and management make it even more difficult to define "adequate," especially when "ecosystem-based management" is itself not well-defined. In attempting to describe the data collection and assessment needs for the latter, the authors took a pragmatic approach, rather than trying to estimate the resources required to develop a knowledge base about the fine-scale detailed distributions, abundances, and associations of all marine species. Thus, the specified resource requirements will not meet the expectations of some stakeholders. In addition, the Stock Assessment Improvement Plan is designed to be complementary to other related plans, and therefore does not duplicate the resource requirements detailed in those plans, except as otherwise noted.

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The offshore shelf and canyon habitats of the OCNMS are areas of high primary productivity and biodiversity that support extensive groundfish fisheries. Recent acoustic surveys conducted in these waters have indicated the presence of hard-bottom substrates believed to harbor unique deep-sea coral and sponge assemblages. Such fauna are often associated with shallow tropical waters, however an increasing number of studies around the world have recorded them in deeper, cold-water habitats in both northern and southern latitudes. These habitats are of tremendous value as sites of recruitment for commercially important fishes. Yet, ironically, studies have shown how the gear used in offshore demersal fishing, as well as other commercial operations on the seafloor, can cause severe physical disturbances to resident benthic fauna. Due to their exposed structure, slow growth and recruitment rates, and long life spans, deep-sea corals and sponges may be especially vulnerable to such disturbances, requiring very long periods to recover. Potential effects of fishing and other commercial operations in such critical habitats, and the need to define appropriate strategies for the protection of these resources, have been identified as a high-priority management issue for the sanctuary.

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The priority management goal of the National Marine Sanctuaries Program (NMSP) is to protect marine ecosystems and biodiversity. This goal requires an understanding of broad-scale ecological relationships and linkages between marine resources and physical oceanography to support an ecosystem management approach. The Channel Islands National Marine Sanctuary (CINMS) is currently reviewing its management plan and investigating boundary expansion. A management plan study area (henceforth, Study Area) was described that extends from the current boundary north to the mainland, and extends north to Point Sal and south to Point Dume. Six additional boundary concepts were developed that vary in area and include the majority of the Study Area. The NMSP and CINMS partnered with NOAA’s National Centers for Coastal Ocean Science Biogeography Team to conduct a biogeographic assessment to characterize marine resources and oceanographic patterns within and adjacent to the sanctuary. This assessment includes a suite of quantitative spatial and statistical analyses that characterize biological and oceanographic patterns in the marine region from Point Sal to the U.S.-Mexico border. These data were analyzed using an index which evaluates an ecological “cost-benefit” within the proposed boundary concepts and the Study Area. The sanctuary resides in a dynamic setting where two oceanographic regimes meet. Cold northern waters mix with warm southern waters around the Channel Islands creating an area of transition that strongly influences the regions oceanography. In turn, these processes drive the biological distributions within the region. This assessment analyzes bathymetry, benthic substrate, bathymetric life-zones, sea surface temperature, primary production, currents, submerged aquatic vegetation, and kelp in the context of broad-scale patterns and relative to the proposed boundary concepts and the Study Area. Boundary cost-benefit results for these parameters were variable due to their dynamic nature; however, when analyzed in composite the Study Area and Boundary Concept 2 were considered the most favorable. Biological data were collected from numerous resource agencies and university scientists for this assessment. Fish and invertebrate trawl data were used to characterize community structure. Habitat suitability models were developed for 15 species of macroinvertebrates and 11 species of fish that have significant ecological, commercial, or recreational importance in the region and general patterns of ichthyoplankton distribution are described. Six surveys of ship and plane at-sea surveys were used to model marine bird diversity from Point Arena to the U.S.-Mexico border. Additional surveys were utilized to estimate density and colony counts for nine bird species. Critical habitat for western snowy plover and the location of California least tern breeding pairs were also analyzed. At-sea surveys were also used to describe the distribution of 14 species of cetaceans and five species of pinnipeds. Boundary concept cost-benefit indices revealed that Boundary Concept 2 and the Study Area were most favorable for the majority of the species-specific analyses. Boundary Concept 3 was most favorable for bird diversity across the region. Inadequate spatial resolution for fish and invertebrate community data and incompatible sampling effort information for bird and mammal data precluded boundary cost-benefit analysis.

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The mission of NOAA’s Office of National Marine Sanctuaries (ONMS) is to serve as the trustee for a system of marine protected areas, to conserve, protect and enhance biodiversity. To assist in accomplishing this mission, the ONMS has developed a partnership with NOAA’s Center for Coastal Monitoring and Assessment’s Biogeography Branch (CCMA-BB) to conduct biogeographic assessments of marine resources within and adjacent to the marine waters of NOAA’s National Marine Sanctuaries (Kendall and Monaco, 2003). Biogeography is the study of spatial and temporal distributions of organisms, their associated habitats, and the historical and biological factors that influence species’ distributions. Biogeography provides a framework to integrate species distributions and life history data with information on the habitats of a region to characterize and assess living marine resources within a sanctuary. The biogeographic data are integrated in a Geographical Information System (GIS) to enable visualization of species’ spatial and temporal patterns, and to predict changes in abundance that may result from a variety of natural and anthropogenic perturbations or management strategies (Monaco et al., 2005; Battista and Monaco, 2004). Defining biogeographic patterns of living marine resources found throughout the Northwestern Hawaiian Islands (NWHI) was identified as a priority activity at a May 2003 workshop designed to outline scientifi c and management information needs for the NWHI (Alexander et al., 2004). NOAA’s Biogeography Branch and the Papahanaumokuakea Marine National Monument (PMNM) under the direction of the ONMS designed and implemented this biogeographic assessment to directly support the research and management needs of the PMNM by providing a suite of spatially-articulated products in map and tabular formats. The major fi ndings of the biogeographic assessment are organized by chapter and listed below.

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The Virginia Aquarium & Marine Science Center Foundation’s Stranding Response Program (VAQS) was awarded a grant in 2008 to conduct life history analysis on over 10 years of Tursiops truncatus teeth and gonad samples from stranded animals in Virginia. A major part of this collaborative grant included a workshop involving life historians from Hubbs-Sea World Research Institute (HSWRI), NOS, Texas A & M University (TAMU), and University of North Carolina Wilmington (UNCW). The workshop was held at the NOAA Center for Coastal Environmental Health & Biomolecular Research in Charleston, SC on 7-9 July 2009. The workshop convened to 1) address current practices among the groups conducting life history analysis, 2) decide on protocols to follow for the collaborative Prescott grant between VAQS and HSWRI, 3) demonstrate tissue preparation techniques and discuss shortcuts and pitfalls, 4) demonstrate data collection from prepared testes, ovaries, and teeth, and 5) discuss data analysis and prepare an outline and timeline for a future manuscript. The workshop concluded with discussions concerning the current collaborative Tursiops Life History Prescott grant award and the beginnings of a collaborative Prescott proposal with members of the Alliance of Marine Mammal Parks and Aquariums to further clarify reproductive analyses. This technical memorandum serves as a record of this workshop.

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In India the chief marine timber boring organisms are 2 species of Martesia, 28 species of shipworms, 4 species and a variety of Sphaeroma and 9 species of Limnoria besides bacteria and fungi. The occurrence, abundance and activity of the various species of borers show remarkable variations and fluctuations in the different harbours of India, each harbour or area having its own dominant set of species and an assemblage of less important forms. These species have their own characteristic preferences, life history and seasons of attachment and a scheme evolved for one locality may prove ineffective for another. Through a delicate and complex ecological adjustment the borers occurring in a locality have reached an interrelationship reducing interspecific and intraspecific competition. The seasons of settlement of the dominant borers in the different harbours of India are indicated. The need for a detailed biological enquiry is stressed.