964 resultados para Actinobacteria, targed with HGC69a oligonucleotides FISH-probe


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This report provides an assessment of recent investigations into endocrine disruption in fresh and saltwater species of fish. Most work to date has concen-trated on reproductive endocrine disruption. Laboratory studies have shown a variety of synthetic and natural chemicals including certain industrial intermediates, PAHs, PCBs, pesticides, dioxins, trace elements and plant sterols can interfere with the endocrine system in fish. The potency of most of these chemicals, however, is typically hundreds to thousands of times less than that of endog-enous hormones. Evidence of environmental endocrine disruption ranges from the presence of female egg proteins in males and reduced levels of endogenous hormones in both males and females, to gonadal histopathologies and intersex (presence of ovotestes) fish. Overt endocrine disruption in fish does not appear to be a ubiquitous environmental phenomenon, but rather more likely to occur near sewage treatment plants, pulp and paper mills, and in areas of high organic chemical contamination. However, more wide-spread endocrine disruption can occur in rivers with smaller flows and correspondingly large or numerous wastewater inputs. Some of the most severe examples of endocrine disruption in fish have been found adjacent to sewage treatment plants. Effects are thought to be caused prima-rily by natural and synthetic estrogens and to a lesser extent by the degradation products of alkylphenol poly-ethoxylate surfactants. Effects found in fish near pulp and paper mills include reduced levels of estrogens and androgens as well as masculinization of females, and has been linked to the presence of β-sitosterol, a plant sterol. Effects seen in areas of heavy industrial activity typically include depressed levels of estrogens and androgens as well as reduced gonadal growth, and may be linked to the presence of PAHs, PCBs, and possibly dioxins. At this time, however, there is no clear indication that large populations of fish are being seriously impacted as a result of endocrine disruption, although additional work is needed to address this possibility. (PDF contains 63 pages)

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The four main objectives of this case study are: 1. Understanding market chains: an overview of the market chain from Indonesian reefs to international retail, with greater detail for case study sites. 2. Identifying poor people in the market chains: including people involved in the chain of custody and others who may be indirectly involved or impacted. 3. Understanding the influence of the marine ornamentals trade on the livelihoods of poor people: the case study looks specifically for underlying as well as obvious factors contributing to poverty reduction, and identify examples of better practice for poverty reduction in the marine ornamentals trade, including examples of positive livelihood outcomes from participation of poor people. 4. Identifying recommendations to improve poor people’s livelihoods. (PDF contains 286 pages)

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The Flower Garden Banks are topographic features on the edge of the continental shelf in the northwest Gulf of Mexico. These banks are approximately 175 km southeast of Galveston, Texas at 28° north latitude and support the northernmost coral reefs on the North American continental shelf. The East and West Flower Garden Banks (EFG and WFG) and Stetson Bank, a smaller sandstone bank approximately 110 km offshore, are managed and protected as the Flower Garden Banks National Marine Sanctuary (FGBNMS). As part of a region-wide initiative to assess coral reef condition, the benthic and fish communities of the EFG and WFG were assessed using the Atlantic and Gulf Rapid Reef Assessment (AGRRA) protocol. The AGRRA survey was conducted during a week-long cruise in August 1999 that was jointly sponsored by the FGBNMS and the Reef Environmental Education Foundation (REEF). A total of 25 coral transects, 132 algal quadrats, 24 fish transects, and 26 Roving Diver (REEF) surveys were conducted. These surveys revealed reefs with high coral cover, dominated by large, healthy corals, little macroalgae, and healthy fish populations. The percent live coral cover was 53.9 and 48.8 at the WFG and EFG, respectively, and the average colony diameter was 93 and 81 cm. Fish diversity was lower than most Caribbean reefs, but large abundances and size of many species reflected the low fishing pressure on the banks. The benthic and fish assemblages at the EFG and WFG were similar. Due to its near pristine conditions, the FGB data will prove to be a valuable component in the AGRRA database and its resulting scale of reef condition for the region. (PDF contains 22 pages.)

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There is a clear need to develop fisheries independent methods to quantify individual sizes, density, and three dimensional characteristics of reef fish spawning aggregations for use in population assessments and to provide critical baseline data on reproductive life history of exploited populations. We designed, constructed, calibrated, and applied an underwater stereo-video system to estimate individual sizes and three dimensional (3D) positions of Nassau grouper (Epinephelus striatus) at a spawning aggregation site located on a reef promontory on the western edge of Little Cayman Island, Cayman Islands, BWI, on 23 January 2003. The system consists of two free-running camcorders mounted on a meter-long bar and supported by a SCUBA diver. Paired video “stills” were captured, and nose and tail of individual fish observed in the field of view of both cameras were digitized using image analysis software. Conversion of these two dimensional screen coordinates to 3D coordinates was achieved through a matrix inversion algorithm and calibration data. Our estimate of mean total length (58.5 cm, n = 29) was in close agreement with estimated lengths from a hydroacoustic survey and from direct measures of fish size using visual census techniques. We discovered a possible bias in length measures using the video method, most likely arising from some fish orientations that were not perpendicular with respect to the optical axis of the camera system. We observed 40 individuals occupying a volume of 33.3 m3, resulting in a concentration of 1.2 individuals m–3 with a mean (SD) nearest neighbor distance of 70.0 (29.7) cm. We promote the use of roving diver stereo-videography as a method to assess the size distribution, density, and 3D spatial structure of fish spawning aggregations.

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Submersible surveys at numerous reefs and banks in the northwestern Gulf of Mexico (NWGOM) were conducted as part of the Sustainable Seas Expedition (SSE) during July/August 2002 to identify reef fish communities, characterize benthic habitats, and identify deep coral reef ecosystems. To identify the spatial extent of hard bottom reef communities, the Flower Garden Banks National Marine Sanctuary (FGBNMS) and the U.S. Geological Survey (USGS) mapped approximately 2000 km2 of the Northwestern Gulf of Mexico (NWGOM) continental shelf during June 2002 with high-resolution multibeam bathymetry. Previous investigations conducted on the features of interest (with the exceptions of East and West Flower Garden and Sonnier Banks, accessible by SCUBA) had not been conducted since the 1970s and 1980s, and did not have the use of high-resolution maps to target survey sites. The base maps were instrumental in navigating submersibles to specific features at each study site during the Sustainable Seas Expedition (SSE)—a submersible effort culminating from a partnership between the National Atmospheric and Oceanic Administration (NOAA) and the National Geographic Society (NGS). We report the initial findings of our submersible surveys, including habitat and reef fish diversity at McGrail, Alderdice, and Sonnier Banks. A total of 120 species and 40,724 individuals were identified from video surveys at the three banks. Planktivorous fishes constituted over 87% by number for the three banks, ranging from 81.4% at Sonnier Banks to 94.3% at Alderdice Bank, indicating a direct link to pelagic prey communities, particularly in the deep reef zones. High numbers of groupers, snappers, jacks, and other fishery species were observed on all three features. These sites were nominated as Habitat Areas of Particular Concern (HAPC) by the Gulf of Mexico Fishery Council in March 2004. Data obtained during this project will contribute to benthic habitat characterization and assessment of the associated fish communities through future SCUBA, ROV, and submersible missions, and allow comparisons to other deep reef ecosystems found throughout the Gulf of Mexico and western Atlantic Ocean.

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Functional linkage between reef habitat quality and fish growth and production has remained elusive. Most current research is focused on correlative relationships between a general habitat type and presence/absence of a species, an index of species abundance, or species diversity. Such descriptive information largely ignores how reef attributes regulate reef fish abundance (density-dependent habitat selection), trophic interactions, and physiological performance (growth and condition). To determine the functional relationship between habitat quality, fish abundance, trophic interactions, and physiological performance, we are using an experimental reef system in the northeastern Gulf of Mexico where we apply advanced sensor and biochemical technologies. Our study site controls for reef attributes (size, cavity space, and reef mosaics) and focuses on the processes that regulate gag grouper (Mycteroperca microlepis) abundance, behavior and performance (growth and condition), and the availability of their pelagic prey. We combine mobile and fixed-active (fisheries) acoustics, passive acoustics, video cameras, and advanced biochemical techniques. Fisheries acoustics quantifies the abundance of pelagic prey fishes associated with the reefs and their behavior. Passive acoustics and video allow direct observation of gag and prey fish behavior and the acoustic environment, and provide a direct visual for the interpretation of fixed fisheries acoustics measurements. New application of biochemical techniques, such as Electron Transport System (ETS) assay, allow the in situ measurement of metabolic expenditure of gag and relates this back to reef attributes, gag behavior, and prey fish availability. Here, we provide an overview of our integrated technological approach for understanding and quantifying the functional relationship between reef habitat quality and one element of production – gag grouper growth on shallow coastal reefs.

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ENGLISH: Extensive live-box experiments were conducted during 1958, 1959, and 1960 to test the efficacy of various tags and marks for use with anchovetas, and to test the effects of the use of anesthetics and antibiotics with the tagging. A total of 12,767 fish was involved in 72 experiments during the three years. Daily records of the mortalities and shedding were kept. Slightly over 7 months was the longest period of time any of the experiments was maintained. SPANISH: Durante 1958, 1959 Y 1960 se hicieron extensos experimentos en viveros para probar la eficacia del uso de varias marcas en las anchovetas y para ensayar los efectos del empleo de anestésicos y antibióticos en el momento de la operación de marcación. En estos tres años se utilizó un total de 12,767 peces en 72 experimentos. Se hicieron anotaciones diarias de la mortalidad y del desprendimiento de las marcas. El período más largo de duración de un experimento sobrepasó ligeramente los 7 meses.

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Many sources of information that discuss currents problems of food security point to the importance of farmed fish as an ideal food source that can be grown by poor farmers, (Asian Development Bank 2004). Furthermore, the development of improved strains of fish suitable for low-input aquaculture such as Tilapia, has demonstrated the feasibility of an approach that combines “cutting edge science” with accessible technology, as a means for improving the nutrition and livelihoods of both the urban poor and poor farmers in developing countries (Mair et al. 2002). However, the use of improved strains of fish as a means of reducing hunger and improving livelihoods has proved to be difficult to sustain, especially as a public good, when external (development) funding sources devoted to this area are minimal1. In addition, the more complicated problem of delivery of an aquaculture system, not just improved fish strains and the technology, can present difficulties and may go explicitly unrecognized (from Sissel Rogne, as cited by Silje Rem 2002). Thus, the involvement of private partners has featured prominently in the strategy for transferring to the public technology related to improved Tilapia strains. Partnering with the private sector in delivery schemes to the poor should take into account both the public goods aspect and the requirement that the traits selected for breeding “improved” strains meet the actual needs of the resource poor farmer. Other dissemination approaches involving the public sector may require a large investment in capacity building. However, the use of public sector institutions as delivery agents encourages the maintaining of the “public good” nature of the products.

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The 13th Annual Larval Fish Conference and Annual Meeting of the American Fisheries Society Early Life History Section cohosted by Mote Marine Laboratory, United States, and the Instituto Nacional de la Pesca, Mexico, were held 21-26 May 1989, in Merida, Yucatan, Mexico. The purpose of holding the meeting in Mexico was to encourage the participation of our Latin American and Caribbean colleagues and to provide a forum for the exchange of ideas and information among researchers working in the Americas. More than 150 participants represented 24 U.S. states, the District of Columbia, and 13 foreign countries including Mexico, Canada, Puerto Rico, Costa Rico, Panama, Cuba, Columbia, Chile, Peru, Brazil, Argentina, South Africa, and West Germany. The Conference began with registration and a social in the courtyard patio of the Merida Holiday Inn. Fresh red grouper, the most important commercial finfish species of the State of Yucatan, was prepared and served by the hotel staff, courtesy of CPI, Itzamex, and the Terramar Trading Company. (PDF file contains 146 pages.)

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This study examined the efficiency of fish diversion and survivorship of diverted fishes in the San Onofre Nuclear Generating Station Fish Return System in 1984 and 1985. Generally, fishes were diverted back to the ocean with high frequency, particularly in 1984. Most species were diverted at rates of 80% or more. Over 90% of the most abundant species, Engraulis mordax, were diverted. The system worked particularly well for strong-swimming forms such as Paralobrax clothratus, Atherinopsis californiensis, and Xenistius californiensis, and did not appreciably divert weaker-swimming species such as Porichthys notatus, Heterostichus rostratus, and Syngnathus sp. Return rates of some species were not as high in 1985 as in 1984. Individuals of most tested species survived both transit through the fish return system and 96 hours in a holding net. Some species, such as E. mordox, X. californiensis, and Umbrina roncador, experienced tittle or no mortality. Survivorship of Seriphus politus was highly variable and no Anchoa delicatissima survived. (PDF file contains 22 pages.)

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Routine biostatistical port sampling data and landings records collected from the gulf menhaden purse seine fishery between 1974 and 1985 are updated. During most of the period, a total of 11 menhaden reduction plants operated in Mississippi and Louisiana, and the number of vessels in the purse seine fleet varied from 71 to 82. Total annual landings ranged from 447,100 metric tons in 1977 to the record landings for the fishery of 982,800 metric tons in 1984. Age-I and -2 gulf menhaden annually comprised almost 96% of the landings. Estimated total numbers of menhaden landed varied from 4,510.5 million in 1975 to 11,154.9 million in 1985. Annual mean lengths and weights of sampled fish-at-age showed lillie variation. Nominal or observed fishing effort gradually increased through Ihe 1970s and 1980s, reaching 655,800 vessel-ton-weeks in 1983. (PDF file contains 14 pages.)

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This report summarizes (I) annual purse seine landings of Atlantic menhaden, Brevoortia tyrannus, for 1972-84, (2) estimated numbers of fish caught by fishing area. (3) estimates of nominal fishing effort and catch-per-unit-effort, (4) mean fish length and weight, and (5) major changes in the fishery. During the 1970s stock size and recruitment increased and the age composition broadened. reversing trends witnessed during the fishery's decline in the 1960s. Landings steadily improved and by 1980 the total coast wide landings exceeded 400,000 metric tons. Nevertheless, the character of the fishery changed considerably. Eleven reduction plants processed fish at seven ports in 1972, but in 1984 only eight plants operated at live ports. Beginning in the mid-1960s the center of fishing aclivity shifted from the Middle Atlantic area to the Chesapeake Bay area, which has continued to dominate the fishery in landings and effort through the 1970s and 1980s. During this period the average size and age of fish in the catches declined. (PDF file contains 30 pages.)

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Proliferation of water withdrawals and new pump intake and screen designs has occurred with the growth of irrigated agriculture along the Columbia and Snake Rivers. Concern for the protection of anadromous and resident fish populations resulted in formulation of a survey of the water withdrawal systems. The survey included distribution studies of juvenile fish near pump sites and field inspection of those sites to determine adequacy of screening for protection of fish. A total of 225 sites were inspected in 1979 and 1980, with a follow-up inspection of 95 sites in 1982. Results indicated a definite trend toward lack of concern for the condition of fish protective facilities. Only 4 out of 22 sites not meeting criteria in 1979 had been upgraded to acceptable conditions. Of more concern, 13 of the sites meeting criteria in 1979 were below criteria when reinspected in 1982. Some of the discrepancies included lack of protective screens, poorly maintained screens, and screens permitting excessive velocity that could result in impingement of larvae or small fish. A conclusion from these surveys is that if adequate protection for fish is to exist, screens for water withdrawals need to be properly installed, inspected, and maintained. (PDF file contains 40 pages.)

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Taxonomic descriptions, line drawings, and references are given for the 30 named and 5 unnamed species of North American fish Eimeriidae. In addition, a key was developed based on available morphologic data to distinguish between similar species. Taxa are divided into two genera: Eimeria (27 species) which are tetr&sporocystic with dizoic, nonbivalved sporocysts, and Goussia (3 species) which are tetrasporocystic with dizoic, bivalved sporocysts that lack Stleda bodies and have sporocyst walls composed of two longitudinal valves. (PDF file contains 24 pages.)

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These guidelines have been produced to support the implementation of the Code of Conduct for Responsible Fisheries particularly with regard to the need for responsibility in the post– harvest sector of the fish producing industry. The industry that produces fish for food has three major areas of responsibility: to the consumer of the food to ensure that it is safe to eat, is of expected quality and nutritional value, to the resource to ensure that it is not wasted and to the environment to ensure that negative impacts are minimized. In addition the industry has a responsibility to itself to ensure the continued ability of many millions of people throughout the world to earn a gainful living from working within the industry. Article 11.1 of the Code of Conduct for Responsible Fisheries and other related parts of the Code are concerned particularly with these responsibilities. This publication provides annotation to and guidance on these articles to assist those charged with implementation of the Code to identify possible courses of action necessary to ensure that the industry is conducted in a sustainable manner. (PDF contains 42 pages)