17 resultados para Data and Information

em Aquatic Commons


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A two day workshop was convened on February 2-3, 1998 in Charleston, SC with 20 invited experts in various areas of sea turtle research. The goal of this workshop was to review current information on sea turtles with repect to health and identify data gaps. The use of a suite of health assessment indicators will provide insight on the health status of sea turtle populations. Since the relationship of health factors of sea turtles is limited, a seconde workshop was planned. Using a tiered approach, the first workshop we identified and reviewed the available, pertinent baseline information and data gaps. The second workshop will focus on developing the framework for the research plan. The workshops will address the use of integrated set of health parameters; specific objectives are: 1) Identify reliable indicators of health in sea turtles: assess advantages and disadvantages; determine new indicators/biomarkers which may be useful; 2) Review existing sea turtle field sampling projects; 3) Identify field projects suitable for inclusion for health assessment sampling; 4) Identify data gaps, particularly environmental characterization; 5) Identify new health assessment sampling sites, including reference site(s); and 6) Develop integrated five-year research plan, with focus on health assessment of environmental characterization. (PDF contains 174 pages)

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This is a report on the Analysis of Data and a Prioritisation of Sites at the Cheshire Meres by the Institute of Freshwater Ecology. The report addresses data collected by the Agency for 24 basin sites in Cheshire. At least two samples were collected from each site, though not simultaneously. Sites were visited in May/June and in November. The determinands are standard and they included: water, temperature, conductivity, pH, DO, fractional white light penetration, TSS, chlorophyll, TP, ortho-phosphate, nitrate-, nitrite-, ammonium and silicate. Though concentrations were often higher than for other lakes in the region, rather exceeding criteria for classification as eutrophic lakes, the results confirmed that the series of lakes is, naturally, highly eutrophic and nothing in the present data differs so far from expectation that is persuasive that the ecosystems are reacting adversely to environmental stress. The data set is review and summarised, site-by-site, in an appendix. The grounds for prioritisation are discussed. Whether or not this preferred prioritised option is adopted, the Agency is recommended to review the way it carries out monitoring. The determinands and the sampling frequency need to be geared to the information that is required.

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In the face of dramatic declines in groundfish populations and a lack of sufficient stock assessment information, a need has arisen for new methods of assessing groundfish populations. We describe the integration of seafloor transect data gathered by a manned submersible with high-resolution sonar imagery to produce a habitat-based stock assessment system for groundfish. The data sets used in this study were collected from Heceta Bank, Oregon, and were derived from 42 submersible dives (1988–90) and a multibeam sonar survey (1998). The submersible habitat survey investigated seafloor topography and groundfish abundance along 30-minute transects over six predetermined stations and found a statistical relationship between habitat variability and groundfish distribution and abundance. These transects were analyzed in a geographic information system (GIS) by using dynamic segmentation to display changes in habitat along the transects. We used the submersible data to extrapolate fish abundance within uniform habitat patches over broad areas of the bank by means of a habitat classification based on the sonar imagery. After applying a navigation correction to the submersible-based habitat segments, a good correlation with major boundaries on the backscatter and topographic boundaries on the imagery were apparent. Extrapolation of the extent of uniform habitats was made in the vicinity of the dive stations and a preliminary stock assessment of several species of demersal fish was calculated. Such a habitat-based approach will allow researchers to characterize marine communities over large areas of the seafloor.

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The changes in time and location of surface temperature from a water body has an important effect on climate activities, marine biology, sea currents, salinity and other characteristics of the seas and lakes water. Traditional measurement of temperature is costly and time consumer due to its dispersion and instability. In recent years the use of satellite technology and remote sensing sciences for data acquiring and parameter and lysis of climatology and oceanography is well developed. In this research we used the NOAA’s Satellite images from its AVHRR system to compare the field surface temperature data with the satellite images information. Ten satellite images were used in this project. These images were calibrated with the field data at the exact time of satellite pass above the area. The result was a significant relation between surface temperatures from satellite data with the field work. As the relative error less than %40 between these two data is acceptable, therefore in our observation the maximum error is %21.2 that can be considered it as acceptable. In all stations the result of satellite measurements is usually less than field data that cores ponds with the global result too. As this sea has a vast latitude, therefore the different in the temperature is natural. But we know this factor is not the only cause for surface currents. The information of all satellites were images extracted by ERDAS software, and the “Surfer” software is used to plot the isotherm lines.

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Information on the biology and fisheries of cobia, Rachycentron canadum, is compiled and reviewed in the FAD species synopsis style. Topics include taxonomy, morphology, distribution, reproduction, pre-adult and adult stages, food, growth, migration, population characteristics, and various aspects of exploitation. Data and information were obtained from unpublished as well as published sources. Cobia, the only species in the family Rachycentridae, is a migratory pelagic fish that occurs in tropical and subtropical seas of the world, except in the central and eastern Pacific Ocean. In the western Atlantic Ocean, spawning occurs during the warm months. Eggs and larvae are planktonic. Females grow faster than males: at 1 year, females are 36 cm FL and 0.4 kg; at 4 years, 99 cm and 11 kg; and at 8 years, 137 cm and 31 kg. Comparable data for males are: at 1 year, 31 cm and 0.3 kg; 4 years, 82 cm and 6 kg; and 8 years, 108 cm and 15 kg. Sexual maturity is attained by males at about 52 cm FL in their second year and by females at about 70 cm in their third year. Fecundity for females 100-125 cm FL varies from 1.9 to 5.4 million eggs. Cobia favor crustaceans for food, but will feed on other invertebrates and fishes as well. They attain a maximum size of over 60 kg. Cobia are fished both commercially and recreationally. Commercially, they are usually caught incidentally in both hook-and-Iine and net fISheries. In the United States, which ranks behind Pakistan, Mexico, and the Philippines in commercial production of cobia, recreational landings exceed commercial landings by more than ten-fold. (PDF file contains 32 pages.)

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After several years of surveys on the Kainji Lake fisheries activities by the Nigerian German Kainji Lake Fish promotion Project (KLFPP) trends regarding catches, yield and other parameter begin to emerge. However, it became obvious that some of the data were not quite as accurate as they were believed to be. Looking at the different editions of the statistical bulletin of Kainji Lake, concerning one given fisheries parameter, sometimes it is possible to reveal inconsistencies and unexplained trends. As compared to the survey method, PRA is primarily for analysis of differences in local phenomenon and processes. Therefore, PRA was used as a complementary tool to enhance the knowledge on issues like fisher women, entrepreneurs, gear ownership structure, mode of operation by owners of large gear number, preference in the use of twine and nylon gill nets, and reasons for misinformation on the number of fishing equipment owned by entrepreneurs, which cannot be done with frame survey. PRA techniques like timeline, mapping, seasonal calendar, transect walk and key informant interviews were utilized in the study process

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This document presents ex-ante impact evaluations of research for development projects related to aquaculture in Bangladesh, Malawi and Ghana. The Ghana chapter also includes an ex-ante evaluation of a fisheries project. The case studies utilized preliminary versions of guidelines developed specifically for ex-ante evaluations of aquaculture and fisheries projects. The guidelines, found in A Practical Guide for Ex-Ante Impact Evaluations in Fisheries and Aquaculture, are designed to provide an approach for a qualitative examination of the potential for a project to deliver impacts. Using a conceptual framework based on the outcome focus of results-based management, the guidelines stress careful examination of the setting, internal consistency, a sound theory of change, and an examination of stakeholders’ interests and potential partnerships. The case study reports illustrate the variability with which the guidelines may be interpreted and applied. The different teams, operating with limited time and budget that constrained the collection of new data, were forced to utilize existing secondary data and information and consult with key stakeholders to complete their analyses. The varying levels of reporting reflect the differences among the cases in the amounts of existing information and variety of stakeholders potentially involved in the projects being examined.

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In 2006, the National Marine Fisheries Service, NOAA, initiated development of a national bycatch report that would provide bycatch estimates for U.S. commercial fisheries at the fishery and species levels for fishes, marine mammals, sea turtles, and seabirds. As part of this project, the need to quantify the relative quality of available bycatch data and estimation methods was identified. Working collaboratively with fisheries managers and scientists across the nation, a system of evaluation was developed. Herein we describe the development of this system (the “tier system”), its components, and its application. We also discuss the value of the tier system in allowing fisheries managers to identify research needs and efficiently allocate limited resources toward those areas that will result in the greatest improvement to bycatch data and estimation quality.

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NOAA’s National Centers for Coastal Ocean Science (NCCOS) conducts and supports research, monitoring, assessments, and technical assistance to meet NOAA’s coastal stewardship and management responsibilities. In 2001 the Biogeography Branch of NCCOS partnered with NOAA’s National Marine Sanctuary Program (NMSP) to conduct biogeographic assessments to support the management plan updates for the sanctuaries. The first biogeographic assessment conducted in this partnership focused on three sanctuaries off north/ central California: Cordell Bank, Gulf of the Farallones and Monterey Bay. Phase I of this assessment was conducted from 2001 to 2004, with the primary goal to identify and gather the best available data and information to characterize and identify important biological areas and time periods within the study area. The study area encompasses the three sanctuaries and extends along the coastal ocean off California from Pt. Arena to Pt. Sal (35°-39°N). This partnership project was lead by the NCCOS Biogeography Branch, but included over 90 contributors and 25 collaborating institutions. Phase I results include: 1) a report on the overall assessment that includes hundreds of maps, tables and analyses; 2) an ecological linkage report on the marine and estuarine ecosystems along the coast of north/central California, and 3) related geographic information system (GIS) data and other summary data files, which are available for viewing and download in several formats at the following website: http://ccma.nos.noaa.gov/products/biogeography/canms_cd/welcome.html Phase II (this report) was initiated in the Fall of 2004 to complete the analyses of marine mammals and update the marine bird colony information. Phase II resulted in significant updates to the bird and mammal chapters, as well as adding an environmental settings chapter, which contains new and existing data and maps on the study area. Specifically, the following Phase II topics and items were either revised or developed new for Phase II: •environmental, ecological settings – new maps on marine physiographic features, sea surface temperature and fronts, chlorophyll and productivity •all bird colony or roost maps, including a summary of marine bird colonies •updated at-sea data CDAS data set (1980-2003) •all mammal maps and descriptions •new overall density maps for eight mammal species •new summary pinniped rookery/haulout map •new maps on at-sea richness for cetaceans and pinnipeds •most text in the mammal chapter •new summary tables for mammals on population status and spatial and temporal patterns

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This report presents the results of a two-year investigation and summary of oceanographic satellite data obtained from multiple operational data providers and sources, spanning years of operational data collection. Long-term summaries of Sea Surface Temperature (SST) and SST fronts, Sea Surface Height Anomalies (SSHA), surface currents, ocean color chlorophyll and turbidity, and winds are provided. Merged satellite oceanographic data revealed information on: (1) seasonal cycles and timing of transition periods; (2) linkages between seasonal effects (warming and cooling), upwelling processes and transport; and (3) nutrient/sediment sources, sinks, and physical limiting factors controlling surface response for Olympic Coast marine environments. These data and information can be used for building relevant hind cast models, ecological forecasts, and regional environmental indices (e.g. upwelling, climate, “hot spot”) on biological distribution and/or response in the PNW.

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Bycatch, or the incidental catch of nontarget organisms during fi shing operations, is a major issue in U.S. shrimp trawl fisheries. Because bycatch is typically discarded at sea, total bycatch is usually estimated by extrapolating from an observed bycatch sample to the entire fleet with either mean-per-unit or ratio estimators. Using both field observations of commercial shrimp trawlers and computer simulations, I compared five methods for generating bycatch estimates that were used in past studies, a mean-per-unit estimator and four forms of the ratio estimator, respectively: 1) the mean fish catch per unit of effort, where unit effort was a proxy for sample size, 2) the mean of the individual fish to shrimp ratios, 3) the ratio of mean fish catch to mean shrimp catch, 4) the mean of the ratios of fish catch per time fished (a variable measure of effort), and 5) the ratio of mean fish catch per mean time fished. For field data, different methods used to estimate bycatch of Atlantic croaker, spot, and weakfish yielded extremely different results, with no discernible pattern in the estimates by method, geographic region, or species. Simulated fishing fleets were used to compare bycatch estimated by the fi ve methods with “actual” (simulated) bycatch. Simulations were conducted by using both normal and delta lognormal distributions of fish and shrimp and employed a range of values for several parameters, including mean catches of fish and shrimp, variability in the catches of fish and shrimp, variability in fishing effort, number of observations, and correlations between fish and shrimp catches. Results indicated that only the mean per unit estimators provided statistically unbiased estimates, while all other methods overestimated bycatch. The mean of the individual fish to shrimp ratios, the method used in the South Atlantic Bight before the 1990s, gave the most biased estimates. Because of the statistically significant two- and 3-way interactions among parameters, it is unlikely that estimates generated by one method can be converted or corrected to estimates made by another method: therefore bycatch estimates obtained with different methods should not be compared directly.

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The red porgy, Pagrus pagrus, is an important reef fish in several offshore fisheries along the southeastern United States. We examined samples from North Carolina through southeast Florida from recreational (headboat) and commercial (hook and line) fisheries, as well as samples from a fishery-independent source. Red porgy attain a maximum age of at least 18 years and 733 mm total length. The weight-length relationship is represented by the ln-ln transformed equation: W = 8.85 × 10–6(L)3.06, where W = whole weight in grams, and L = total length in mm. The von Bertalanffy growth equation fitted to the most recent, back-calculated lengths from all the samples is Lt = 644(1 – e –0.15(t + 0.76)). Our study revealed a difference in mean length at age of red porgy from the three sources. Red porgy in fishery-independent collections were smaller at age than specimens examined from fishery-dependent sources. The difference in length-at-age may be related to gear selectivity and have important consequences in the assessment of fish stocks.