962 resultados para Marine invertebrates


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Gray’s Reef National Marine Sanctuary (GRNMS) is located 32.4 km offshore of Sapelo Island, Georgia. The ecological importance of this area is related to the transition between tropical and temperate waters, and the existence of a topographically complex system of ledges. Due to its central location, GRNMS can be used as a focal site to study the accumulation and impacts of marine debris on the Atlantic continental shelf offshore of the Southeast United States. Previously, researchers characterized marine debris in GRNMS and reported that incidence of the debris at the limited densely colonized ledge sites was significantly greater than at sand or sparsely colonized live bottom, and is further influenced by the level of boating activity and physiographic characteristics (e.g., ledge height). Information gleaned from the initial marine debris characterization was used to devise a strategy for prioritizing cleanup and monitoring efforts. However, a significant gap in knowledge was the rate of debris accumulation. The primary objective of this study was to select, mark, and perform initial marine debris surveys at permanent monitoring sites within GRNMS to quantify long-term trends in types, abundance, impacts, and accumulation rates of debris. Ledge sites were selected to compare types, abundance, and accumulation rates of marine debris between a) areas of high and low use and b) short and tall ledges. Nine permanent monitoring sites were marked and initially surveyed in 2007/2008. Surveys were conducted within a 50 x 4 m transect for a total survey area of 200 square meters. All debris was removed and detailed information was taken on the types of debris, quantity, and associations with benthic fauna. Information on associations with benthic fauna included degree of entanglement, type of organism with which it is entangled or resting on, degree of fouling, and visible impacts such as tissue abrasions. Sites were re-surveyed approximately one year later to quantify new accumulation. During the initial survey, a total of ten debris items, totaling 16.3 kg in weight, were removed from two monitoring stations, both “tall” sites within the area of high boat use. Year-one accumulation totaled five items and approximately 7 kg in weight. Similar to the initial survey, all debris was found at sites in the area of high boat use. However, in contrast to the initial survey, two of these items were found on medium-height ledges. Removed items included fishing line, leaders, rope, plastic, and fabric. Although items were often encrusted in benthic biota or entangled on the ledge, impacts such as abrasions or other injuries were not observed. During the 2009 monitoring efforts, volunteer divers were trained to conduct the survey. Monitoring protocols were documented for GRNMS staff and included as an appendix of this report to enable long-term monitoring of sites. Additionally, national reconnaissance data (e.g. satellite, radar, aerial surveys) and other information on known fishing locations were examined for patterns of resource use and correlations with debris occurrence patterns. A previous model predicting the density of marine debris based on ledge features and boat use was refined and the results were used to generate a map of predicted debris density for all ledges.

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Bottlenose dolphins (Tursiops truncatus) inhabit estuarine waters near Charleston, South Carolina (SC) feeding, nursing and socializing. While in these waters, dolphins are exposed to multiple direct and indirect threats such as anthropogenic impacts (egs. harassment with boat traffic and entanglements in fishing gear) and environmental degradation. Bottlenose dolphins are protected under the Marine Mammal Protection Act of 1972. Over the years, the percentage of strandings in the estuaries has increased in South Carolina and, specifically, recent stranding data shows an increase in strandings occurring in Charleston, SC near areas of residential development. During the same timeframe, Charleston experienced a shift in human population towards the coastline. These two trends, rise in estuarine dolphin strandings and shift in human population, have raised questions on whether the increase in strandings is a result of more detectable strandings being reported, or a true increase in stranding events. Using GIS, the trends in strandings were compared to residential growth, boat permits, fishing permits, and dock permits in Charleston County from 1994-2009. A simple linear regression analysis was performed to determine if there were any significant relationships between strandings, boat permits, commercial fishing permits, and crabpot permits. The results of this analysis show the stranding trend moves toward Charleston Harbor and adjacent rivers over time which suggests the increase in strandings is related to the strandings becoming more detectable. The statistical analysis shows that the factors that cause human interaction strandings such as boats, commercial fishing, and crabpot line entanglements are not significantly related to strandings further supporting the hypothesis that the increase in strandings are due to increased observations on the water as human coastal population increases and are not a natural phenomenon. This study has local and potentially regional marine spatial planning implications to protect coastal natural resources, such as the bottlenose dolphin, while balancing coastal development.

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A competitive enzyme-linked immunosorbent assay (cELISA) was developed by using a whole-cell antigen from a marine Brucella sp. isolated from a harbor seal (Phoca vitulina). The assay was designed to screen sera from multiple marine mammal species for the presence of antibodies against marine-origin Brucella. Based on comparisons with culture-confirmed cases, specificity and sensitivity for cetacean samples tested were 73% and 100%, respectively. For pinniped samples, specificity and sensitivity values were 77% and 67%, respectively. Hawaiian monk seal (Monachus schauinslandi; n = 28) and bottlenose dolphin (Tursiops truncatus; n = 48) serum samples were tested, and the results were compared with several other assays designed to detect Brucella abortus antibodies. The comparison testing revealed the marine-origin cELISA to be more sensitive than the B. abortus tests by the detection of additional positive serum samples. The newly developed cELISA is an effective serologic method for detection of the presence of antibodies against marine-origin Brucella sp. in marine mammals.

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We have recently exchanged and integrated into a single database tag detections for conch, teleost and elasmobranch fish from four separately maintained arrays in the U.S. Virgin Islands including the NMFS queen conch array (St. John nearshore), NOAA’s Biogeography Branch array (St. John nearshore & midshelf reef); UVI shelf edge arrays (Marine Conservation District, Grammanik & other shelf edge); NOAA NMFS Apex Predator array COASTSPAN (St. John nearshore). The integrated database has over 7.5 million hits. Data is shared only with consent of partners and full acknowledgements. Thus, the summary of integrated data here uses data from NOAA and UVI arrays under a cooperative agreement. The benefits of combining and sharing data have included increasing the total area of detection resulting in an understanding of broader scale connectivity than would have been possible with a single array. Partnering has also been cost-effectiveness through sharing of field work, staff time and equipment and exchanges of knowledge and experience across the network. Use of multiple arrays has also helped in optimizing the design of arrays when additional receivers are deployed. The combined arrays have made the USVI network one of the most extensive acoustic arrays in the world with a total of 150+ receivers available, although not necessarily all deployed at all times. Currently, two UVI graduate student projects are using acoustic array data.

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NOAA/NCCOS is conducting the following work for the NOAA California Current Integrated Ecosystem Assessment, in support of the NOAA/NMFS Northwest Fisheries Science Center.

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The intent of this field mission was to continue ongoing efforts: (1) to spatially characterize and monitor the distribution, abundance and size of both reef fishes and conch within and around the waters of the Virgin Islands National Park (VIIS) and newly established Virgin Islands Coral Reef National Monument (VICR), (2) to correlate this information to in-situ data collected on associated habitat parameters, (3) to use this information to establish the knowledge base necessary for enacting management decisions in a spatial setting and to establish the efficacy of those management decisions. This work is supported by the National Park Service and NOAA’s Coral Reef Conservation Program’s Caribbean Coral Reef Ecosystem Monitoring Project.

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Various reef types worldwide have inconsistent relationships among fish assemblage parameters and benthic characteristics, thus there is a need to identify factors driving assemblage structure specific to each reef type and locale. Limestone ledges are known to be key habitats for bottom fish on the continental shelf of the southeastern USA, however, the specific factors that link them to fish assemblages have not been quantified. Bottom fishes and habitat characteristics on ledges were surveyed at a study site located centrally in the southeastern USA continental shelf. Species richness, diversity, abundance, and biomass of fish were higher at ledges than on flat bottom. Species richness, abundance, and biomass of fish were well explained by ledge variables including percent cover of sessile invertebrates, total height, and height of undercut recesses. Multivariate analyses based on biomass of individual species at ledges revealed two fish assemblages associated with four ledge types. One assemblage was associated with ledges that were tall, heavily colonized with sessile invertebrates, large in area, and did or did not have undercuts. The other assemblage was associated with ledges that were short, not undercut, smaller in area, and were or were not heavily colonized by invertebrates. Seafloor classification schemes presently used in the region do not adequately capture hard bottom diversity to identify the location and extent of essential fish habitats for ecological and fisheries purposes. Given that ledges cover only ∼1% to 5% of the southeastern USA continental shelf, they merit the highest levels of consideration in regional research, conservation, and management plans.

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The Flower Garden Banks National Marine Sanctuary (FGBNMS) is located in the northwestern Gulf of Mexico approximately 180 km south of Galveston, Texas. The sanctuary’s distance from shore combined with its depth (the coral caps reach to within approximately 17 m of the surface) result in limited exposure of this coral reef ecosystem to natural and human-induced impacts compared to other coral reefs of the western Atlantic. In spite of this, the sanctuary still confronts serious impacts including hurricanes events, recent outbreaks of coral disease, an increase in the frequency of coral bleaching and the massive Diadema antillarum die-off during the mid-1980s. Anthropogenic impacts include large vessel anchoring, commercial and recreational fishing, recreational scuba diving, and oil and gas related activities. The FGBNMS was designated in 1992 to help protect against some of these impacts. Basic monitoring and research efforts have been conducted on the banks since the 1970s. Early on, these efforts focused primarily on describing the benthic communities (corals, sponges) and providing qualitative characterizations of the fish community. Subsequently, more quantitative work has been conducted; however, it has been limited in spatial scope. To complement these efforts, the current study addresses the following two goals put forth by sanctuary management: 1) to develop a sampling design for monitoring benthic fish communities across the coral caps; and 2) to obtain a spatial and quantitative characterization of those communities and their associated habitats.

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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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A reoccurring goal listed during the creation of Marine Protected Areas (MPAs) is to return the region to a former state. However, limited data is available that describes or characterizes this former condition. Data collected from ecosystems with comparatively limited anthropogenic impacts, can provide invaluable information in suggesting what former states may have looked like. One example is the Flower Garden Banks National Marine Sanctuary which is located 180 kilometers off the coast of Texas. These relatively isolated and pristine banks are capped by substantial scleractinian coral communities, forming excellent habitat for over 200 species of fish. While fishing is permitted, it is limited by difficulty of access. In 2006, NOAA’s Biogeography Branch, in collaboration with the Sanctuary, initiated the first quantitative assessment of fish resources throughout the diveable portions of the Sanctuary. The sampling design and methodologies employed were identical to those that the Branch has utilized in other more impacted regions of the US Caribbean. Initial analyses reveal that fish density and species richness at the Sanctuary were almost two times greater than that found within the US Caribbean and biomass was approximately six times higher. This was due in large part to the presence of sizeable piscivores of the genera Mycteroperca and Dermatolepis. The Sanctuary is one of few minimally impacted locations remaining within the Tropical Western Atlantic. As such, these findings should be considered when attempting to establish a former state or evaluate effectiveness of an MPA in meeting its management goals.

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Algae are the most abundant photosynthetic organisms in marine ecosystems and are essential components of marine food webs. Harmful algal bloom or “HAB” species are a small subset of algal species that negatively impact humans or the environment. HABs can pose health hazards for humans or animals through the production of toxins or bioactive compounds. They also can cause deterioration of water quality through the buildup of high biomass, which degrades aesthetic, ecological, and recreational values. Humans and animals can be exposed to marine algal toxins through their food, the water in which they swim, or sea spray. Symptoms from toxin exposure range from neurological impairment to gastrointestinal upset to respiratory irritation, in some cases resulting in severe illness and even death. HABs can also result in lost revenue for coastal economies dependent on seafood harvest or tourism, disruption of subsistence activities, loss of community identity tied to coastal resource use, and disruption of social and cultural practices. Although economic impact assessments to date have been limited in scope, it has been estimated that the economic effects of marine HABs in U.S. communities amount to at least $82 million per year including lost income for fisheries, lost recreational opportunities, decreased business in tourism industries, public health costs of illness, and expenses for monitoring and management. As reviewed in the report, Harmful Algal Research and Response: A Human Dimensions Strategy1, the sociocultural impacts of HABs may be significant, but remain mostly undocumented.

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This poster presents information on the status and trends of coral reef ecosystems in St. Croix, US Virgin Islands (USVI). Data were collected by NOAA’s Center for Coastal Monitoring and Assessment Biogeography Branch (CCMA-BB) from 2001-2006 at 1,275 random locations in and around Buck Island Reef National Monument (BIRNM). The main objective was to quantify changes in fish species and assemblage diversity, abundance, biomass and size structure; to provide spatially explicit information on the distribution of key species or groups of species; and to compare community structure inside versus outside of BIRNM.