19 resultados para Nautical

em Aquatic Commons


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The Channel Islands—sometimes called the Galapagos of North America—are known for their great beauty, rich biodiversity, cultural heritage, and recreational opportunities. In 1980, in recognition of the islands’ importance, the United States Congress established a national park encompassing 5 of California’s Channel Islands (Santa Barbara, Anacapa, Santa Cruz, Santa Rosa, and San Miguel Islands) and waters within 1 nautical mile of the islands. In the same year, Congress declared a national marine sanctuary around each of these islands, including waters up to 6 nautical miles offshore. Approximately 60,000 people visit the Channel Islands each year for aquatic recreation such as fishing, sailing, kayaking, wildlife watching, surfing, and diving. Another 30,000 people visit the islands for hiking, camping, and sightseeing. Dozens of commercial fishing boats based in Santa Barbara, Ventura, Oxnard, and other ports go to the Channel Islands to catch squid, spiny lobster, sea urchin, rockfish, crab, sheephead, flatfish, and sea cucumber, among other species. In the past few decades, advances in fishing technology and the rising number of fishermen, in conjunction with changing ocean conditions and diseases, have contributed to declines in some marine fishes and invertebrates at the Channel Islands. In 1998, citizens from Santa Barbara and Ventura proposed establishment of no-take marine reserves at the Channel Islands, beginning a 4-year process of public meetings, discussions, and scientific analyses. In 2003, the California Fish and Game Commission designated a network of marine protected areas (MPAs) in state waters around the northern Channel Islands. In 2006 and 2007, the National Oceanic and Atmospheric Administration (NOAA) extended the MPAs into the national marine sanctuary’s deeper, federal waters. To determine if the MPAs are protecting marine species and habitats, scientists are monitoring ecological changes. They are studying changes in habitats; abundance and size of species of interest; the ocean food web and ecosystem; and movement of fish and invertebrates from MPAs to surrounding waters. Additionally, scientists are monitoring human activities such as commercial and recreational fisheries, and compliance with MPA regulations. This booklet describes some results from the first 5 years of monitoring the Channel Islands MPAs. Although 5 years is not long enough to determine if the MPAs will accomplish all of their goals, this booklet offers a glimpse of the changes that are beginning to take place and illustrates the types of information that will eventually be used to assess the MPAs’ effectiveness. (PDF contains 24 pages.)

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This cruise report is a summary of a field survey conducted in coastal-ocean waters off Florida from Anclote Key to West Palm Beach and from approximately 1 nautical mile (nm) offshore seaward to the shelf break (100 m). The survey was conducted May 15 - May 28, 2007 on NOAA Ship NANCY FOSTER Cruise NF-07-08-NCCOS. Multiple indicators of ecological condition were sampled synoptically at each of 50 stations throughout the region including 10 stations within the Florida Keys National Marine Sanctuary (FKNMS) using a random probabilistic sampling design. Samples were collected for the analysis of benthic community structure and composition; concentrations of chemical contaminants (metals, pesticides, PAHs, PCBs, PBDEs) in sediments and target demersal biota; nutrient and chlorophyll levels in the water column; and other basic habitat characteristics such as depth, salinity, temperature, dissolved oxygen, pH, sediment grain size, and organic carbon content. The overall purpose of the survey was to collect data to assess the status of ecological condition in coastal-ocean waters of the region, based on these various indicators, and to provide this information as a baseline for determining how environmental conditions may be changing with time. The results will be of value in helping to broaden our understanding of the status of ecological resources and their controlling factors, including impacts of potential ecosystem stressors, in such strategic coastal areas. (PDF contains 34 pages

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This cruise report is a summary of a field survey conducted in coastal-ocean waters of the Mid-Atlantic Bight from Nags Head, North Carolina to Cape Cod, Massachusetts and from approximately 1 nautical mile (nm) of shore seaward to the shelf break (100 m). The survey was conducted May 12 - May 21, 2006 on NOAA Ship NANCY FOSTER Cruise NF-06-06-NCCOS. Multiple indicators of ecological condition were sampled synoptically at each of 49 stations throughout the region using a random probabilistic sampling design. Samples were collected for the analysis of benthic community structure and composition; concentrations of chemical contaminants (metals, pesticides, PAHs, PCBs, PBDEs) in sediments and target demersal biota; nutrient and chlorophyll levels in the water column; and other basic habitat characteristics such as depth, salinity, temperature, dissolved oxygen, pH, sediment grain size, and organic carbon content. The overall purpose of the survey was to collect data to assess the status of ecological condition in coastal-ocean waters of the region, based on these various indicators, and to provide this information as a baseline for determining how environmental conditions may be changing with time. The results will be of value in helping to broaden our understanding of the status of ecological resources and their controlling factors, including impacts of potential ecosystem stressors, in such strategic coastal areas. (18pp.) (PDF contains 24 pages)

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From May 22 to June 4, 2006, NOAA scientists led a research cruise using the ROPOS Remotely Operated Vehicle (ROV) to conduct a series of dives at targeted sites in the Olympic Coast National Marine Sanctuary (OCNMS) with the goal of documenting deep coral and sponge communities. Dive sites were selected from areas for which OCNMS had side scan sonar data indicating the presence of hard or complex substrate. The team completed 11 dives in sanctuary waters ranging from six to 52 hours in length, at depths ranging from 100 to 650 meters. Transect surveys were completed at 15 pre-selected sites, with additional observations made at five other sites. The survey locations included sites both inside and outside the Essential Fish Habitat (EFH) Conservation Area, known as Olympic 2, established by the Pacific Fishery Management Council, enacted on June 12, 2006. Bottom trawling is prohibited in the Olympic 2 Conservation Area for nontribal fishermen. The Conservation Area covers 159.4 square nautical miles or about 15 percent of the sanctuary. Several species of corals and sponges were documented at 14 of the 15 sites surveyed, at sites both inside and outside the Conservation Area, including numerous gorgonians and the stony corals Lophelia pertusa and Desmophyllum dianthus, as well as small patches of the reef building sponge Farrea occa. The team also documented Lophelia sp. and Desmophyllum sp. coral rubble, dead gorgonians, lost fishing gear, and other anthropogenic debris, supporting concerns over potential risks of environmental disturbances to coral health. (PDF contains 60 pages.)

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ENGLISH: Project Little Window was planned to provide some answers to the important scientific question of whether or not the HRIR (high resolution infrared radiometer) sensors aboard NASA and NOAA satellites can provide useful data for much of the oceanographic community. The sensors aboard these satellites were designed in response to the initial needs of meteorologists for temperature measurements integrated over a distance of 5-10 nautical miles and extending over a range from 30°C to about -75°C (i2-4°C). To this end the sensors have been a very powerful tool to the meteorologist in preparing daily weather advisories and in carrying out research. SPANISH: El proyecto Little Window fue planeado para suministrar algunas respuestas al importante tema científico sobre si los captadores (ltsensors") infrarrojos de alta resoluci6n (IRAR) a bordo de los satélites NASA y NOAA, pueden o no proveer datos útiles para la mayor1a de los oceanógrafos. Los captadores a bordo de estos satélites fueron concebidos en respuesta a las necesidades iniciales de los meteor6logos para obtener mediciones de temperatura integradas sobre una distancia de 5-10 millas náuticas, y entre 30°c y aproximadamente -75°C (~2-4°C). Con este fin los captadores han sido un instrumento poderoso para el meteor6logo en la preparaci6n de las informaciones diarias de tiempo y en la realizaci6n de las investigaciones. (PDF contains 171 pages.)

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Three years of weekly sampling from a coastal station and 29 monthly cruises over the whole continental shelf were studied for zooplankton quantitative variation. Settled volumes were preferred to displacement volumes. At the coastal station, near Abidjan, a negative correlation was found between the log2 of zooplankton volume and the preceding fortnight temperature. On the whole shelf, the differences between the 6 considered areas were tested by the variance analysis. There were significative differences in shallow waters only (20 m). During the main cold season, the upwelling of Tabou causes a very important enrichment 30 to 60 nautical miles to the east. Eastwards the plankton drifts and decreases in abundance. The zooplankton maximum is not always inshore, but often in the middle of the shelf and sometimes over the slope. During the little cold season the enrichments caused by coastal upwelling are less abundant and restricted to smaller areas. During the warm season, the waters are uniformly poor. During the cold season, over the 60m depths, the zooplankton maximum lies between 10 and 20 m and seems to sink in deeper waters. In warm season the vertical repartition is rather homogeneous in the first 40 meters. The diel vertical migrations show a very consistent rhythm, varying with the season.

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The U.S. East Coast pelagic longline fishery has a history of interactions with marine mammals, where animals are hooked and entangled in longline gear. Pilot whales (Globicephala spp.) and Risso’s dolphin (Grampus griseus) are the primary species that interact with longline gear. Logistic regression was used to assess the environmental and gear characteristics that influence interaction rates. Pilot whale inter-actions were correlated with warm water temperatures, proximity to the shelf break, mainline lengths greater than 20 nautical miles, and damage to swordfish catch. Similarly, Risso’s dolphin interactions were correlated with geographic location, proximity the shelf break, the length of the mainline, and bait type. The incidental bycatch of marine mammals is likely associated with depredation of the commercial catch and is increased by the overlap between marine mammal and target species habitats. Altering gear characteristics and fishery practices may mitigate incidental bycatch and reduce economic losses due to depredation.

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Marine sportfishing in southern California is a huge industry with annual revenues totaling many billions of dollars. However, the stocks of lingcod and six rockfish species have been declared overfished by the Pacific Fisheries Management Council. As part of a multifaceted fisheries management plan, marine conservation areas, covering many million square nautical miles, have been mandated. To monitor the recovery of the rockfish stocks in these areas, scientists are faced with the following challenges: 1) multiple species of rockfish exist in these areas; 2) the species reside near or on the bottom at depths of 80 to 300 m; and 3) they are low in numerical density. To meet these challenges, multifrequency echosounders, multibeam sonar, and cameras mounted on remotely operated vehicles are frequently used (Reynolds et al., 2001). The accuracy and precision of these echosounder results are largely dependent upon the accuracy of the species classification and target strength estimation (MacLennan and Simmonds, 1992).

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Rockfishes (Sebastes spp.) are an important component of North Pacific marine ecosystems and commercial fisheries. Because the rocky, high-relief substrate that rockfishes often inhabit is inaccessible to standard survey trawls, population abundance assessments for many rockfish species are difficult. As part of a large study to classify substrate and compare complementary sampling tools, we investigated the feasibility of using an acoustic survey in conjunction with a lowered stereo-video camera, a remotely operated vehicle, and a modified bottom trawl to estimate rockfish biomass in untrawlable habitat. The Snakehead Bank south of Kodiak Island, Alaska, was surveyed repeatedly over 4 days and nights. Dusky rockfish (S. variabilis), northern rockfish (S. polyspinis), and harlequin rockfish (S. variegatus) were the most abundant species observed on the bank. Backscatter attributed to rockfish were collected primarily near the seafloor at a mean height off the bottom of 1.5 m. Total rockfish backscatter and the height of backscatter off the bottom did not differ among survey passes or between night and day. Biomass estimates for the 41 square nautical-mile area surveyed on this small, predominantly untrawlable bank were 2350 metric tons (t) of dusky rockfish, 331 t of northern rockfish, and 137 t of harlequin rockfish. These biomass estimates are 5–60 times the density estimated for these rockfish species by a regularly conducted bottom trawl survey covering the bank and the surrounding shelf. This finding shows that bottom trawl surveys can underestimate the abundance of rockfishes in untrawlable areas and, therefore, may underestimate overall population abundance for these species.

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With a focus on white marlin (Tetrapturus albidus), a concurrent electronic tagging and larval sampling effort was conducted in the vicinity of Mona Passage (off southeast Hispaniola), Dominican Republic, during April and May 2003. Objectives were 1) to characterize the horizontal and vertical movement of adults captured from the area by using pop-up satellite archival tags (PSATs); and 2) by means of larval sampling, to investigate whether fish were reproducing. Trolling from a sportfishing vessel yielded eight adult white marlin and one blue marlin (Makaira nigricans); PSAT tags were deployed on all but one of these individuals. The exception was a female white marlin that was unsuitable for tagging because of injury; the reproductive state of its ovaries was examined histologically. Seven of the PSATs reported data summaries for water depth, temperature, and light levels measured every minute for periods ranging from 28 to 40 days. Displacement of marlin from the location of release to the point of tag pop-up ranged from 3l.6 to 267.7 nautical miles (nmi) and a mean displacement was 3.4 nmi per day for white marlin. White and blue marlin mean daily displacements appeared constrained compared to the results of other marlin PSAT tagging studies. White marlin ovarian sections contained postovulatory follicles and final maturation-stage oocytes, which indicated recent and imminent spawning. Neuston tows (n=23) yielded 18 istiophorid larvae: eight were white marlin, four were blue marlin, and six could not be identified to species. We speculate that the constrained movement patterns of adults may be linked to reproductive activity for both marlin species, and, if true, these movement patterns may have several implications for management. Protection of the potentially important white marlin spawning ground near Mona Passage seems warranted, at least until further studies can be conducted on the temporal and spatial extent of reproduction and associated adult movement.

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The data from two years' monitoring of the Tongan seamount fishery were analyzed the two main export species are Pristipomoides filamentosus and Etelis coruscans. K.R. Allen's model was used to obtain estimates of catchability and recruitment and of a surplus production of 737 kg per nautical mile (nm) of 200 m contour. This compared reasonably well to total landings. Using this estimate, the annual surplus production for Tonga's 294 nm of 200 m contour is 217 t. The level of fishing mortality was found to be 0.3/year.

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At her launch on 19 October 1882 in Wilmington, Del., the Albatross was the world’s first large deep-sea oceanographic and fisheries research vessel, and she would go on to have a distinguished 40-year career, ranging from the north Atlantic Ocean to the Gulf of Mexico, around Cape Horn in 1887–88, and into the North Pacific. By 1908, Deputy Fish Commissioner Hugh M. Smith reported that “The Albatross has contributed more to the knowledge of marine biology than has any other vessel.” And, of course, her career continued for another 13 years, being decommissioned in late 1921, serving later as a training vessel for nautical cadets, and disappearing from the records in Hamburg, Germany, in late 1928.

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During 1995 and 1996, the National Marine Fisheries Service (NMFS), conducted pilot studies to develop survey methodology and a sampling strategy for assessment of coastal shark populations in the Gulf of Mexico and western North Atlantic. Longline gear similar to that used in the commercial shark fishery was deployed at randomly selected stations within three depth strata per 60 nautical mile gridf rom Brownsville, Tex. to Cape Ann, Mass. The survey methodology and gear design used in these surveys proved effective for capturing many of the small and large coastal sharks regulated under the auspices of the 1993 Fisheries Management Plan (FMP) for Sharks oft he Atlantic Ocean. Shark catch rates, species composition, and relative abundance documented in these pilot surveys were similar to those reported from observer programs monitoring commercial activities. During 78 survey days, 269 bottom longline sets were completed with 879 sharks captured.

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The Southern Florida Shallow-water Coral Ecosystem Mapping Implementation Plan (MIP) discusses the need to produce shallow-water (~0-40 m; 0-22 fm) benthic habitat and bathymetric maps of critical areas in southern Florida and moderate-depth (~40-200 m; 22 -109 fm) bathymetric maps for all of Florida. The ~0-40 m depth regime generally represents where most hermatypic coral species are found and where most direct impacts from pollution and coastal development occur. The plan was developed with extensive input from over 90 representatives of state regulatory and management agencies, federal agencies, universities, and non-governmental organizations involved in the conservation and management of Florida’s coral ecosystems. Southern Florida’s coral ecosystems are extensive. They extend from the Dry Tortugas in the Florida Keys as far north as St Lucie Inlet on the Atlantic Ocean coast and Tarpon Springs on the Gulf of Mexico coast. Using 10 fm (18 m) depth curves on nautical charts as a guide, southern Florida has as much as 84 percent (30,801 sq km) of 36,812 sq km of potential shallow-water (<10 fm; <18 m) coral ecosystems the tropical and subtropical U.S. Moreover, southern Florida’s coral ecosystems contribute greatly to the regional economy. Coral ecosystem-related expenditures generated $4.4 billion in sales, income, and employment and created over 70,000 full-time and part-time jobs in the region during the recent 12-month periods when surveys were conducted.

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The St. Croix East End Marine Park (STXEEMP) was established in 2003 as the first multi-use marine park managed by the U.S. Virgin Islands Department of Planning and Natural Resources. It encompasses an area of approximately 155 km2 and is entirely within Territorial waters which extend up to 3 nautical miles from shore. As stated in the 2002 management plan, the original goals were to: protect and maintain the biological diversity and other natural values of the area; promote sound management practices for sustainable production purposes; protect the natural resource base from being alienated for other land use purposes that would be detrimental to the area’s biological diversity; and to contribute to regional and national development (The Nature Conservancy, 2002). At the time of its establishment, there were substantial data gaps in knowledge about living marine resources in the St. Croix, and existing data were inadequate for establishing baselines from which to measure the future performance of the various management zones within the park. In response to these data gaps, National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment, Biogeography Branch (CCMA-BB) worked with territorial partners to characterize and assess the status of the marine environment in and around the STXEEMP and land-based stressors that affect them. This project collected and analyzed data on the distribution, diversity and landscape condition of marine communities across the STXEEMP. Specifically, this project characterized (1) landscape and adjacent seascape condition relevant to threats to coral reef ecosystem health, and (2) the marine communities within STXEEMP zones to increase local knowledge of resources exposed to different regulations and stressors.