13 resultados para Final Year

em Aquatic Commons


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Silver King Creek, Alpine County, is the native range of the Federally-threatened Paiute cutthroat trout, Oncorhynchus clarki seleniris. Paiute cutthroat currently inhabit Coyote Valley and Corral Valley creeks, which are tributaries to Silver King Creek below Llewellyn Falls, and also Silver King Creek and tributaries aboye Llewellyn Falls. Rainbow trout, O. mykiss, were introduced into the basin during 1949 and became hybridized with Paiute cutthroat. Chemical treatments attempted by the California Department of Fish and Game (CDFG) in 1964 and 1976 failed to eliminate hybrid trout. A chemical treatment project was again conducted by the CDFG from 1991 through 1993 to eliminate hybrid trout from within the range of Paiute cutthroat. This report presents a summary of events for the first two years of the Silver King Paiute Cutthroat Trout Restoration Project; a more thorough analysis is made of the third and final year of the project. (PDF contains 39 pages.)

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This data report includes the results from Alachua County Environmental Protection Department’s inspections of wastewater treatment plants (WWTP) within Alachua County during the 2006 and 2007 fiscal years (October 2005 – September 2007). Groundwater monitoring data provided to the Florida Department of Environmental Protection Department by the WWTP operators is included for those treatment plants that are required to submit this information (PDF has 44 pages.)

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Rice cultivation at any level in the Sacramento–San Joaquin Delta (existing or expanded) compels the need to quantify surface and subsurface loads of dissolved organic carbon (DOC), disinfection byproduct precursors (DBPPs) and nitrogen. This information can be used to develop Best Management Practices (BMPs) to reduce export of these constituents in order to improve drinking water quality. Although rice cultivation in the Delta is relatively limited, several factors outside of this research could contribute to increased rice acreage in the Delta: • Recently developed rice varieties seem more suitable for the Delta climate than earlier varieties which required warmer conditions; • Previous economic analyses (Appendix A.10) suggest rice is more profitable than corn, a dominant land use in the Delta; • Recent studies on wetlands at Twitchell Island suggest rice production can help mitigate oxidative subsidence (Miller et al. 2000); • The different oxidative states that result from flooding in rice as compared to those found in crops that require drained soils may help control crop specific weeds and nematodes when rice is incorporated into a crop rotation; and • Providing flooded conditions during a greater part of the year than other crops may benefit water birds. ... (PDF contains 249 pages)

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To be in compliance with the Endangered Species Act and the Marine Mammal Protection Act, the United States Department of the Navy is required to assess the potential environmental impacts of conducting at-sea training operations on sea turtles and marine mammals. Limited recent and area-specific density data of sea turtles and dolphins exist for many of the Navy’s operations areas (OPAREAs), including the Marine Corps Air Station (MCAS) Cherry Point OPAREA, which encompasses portions of Core and Pamlico Sounds, North Carolina. Aerial surveys were conducted to document the seasonal distribution and estimated density of sea turtles and dolphins within Core Sound and portions of Pamlico Sound, and coastal waters extending one mile offshore. Sea Surface Temperature (SST) data for each survey were extracted from 1.4 km/pixel resolution Advanced Very High Resolution Radiometer remote images. A total of 92 turtles and 1,625 dolphins were sighted during 41 aerial surveys, conducted from July 2004 to April 2006. In the spring (March – May; 7.9°C to 21.7°C mean SST), the majority of turtles sighted were along the coast, mainly from the northern Core Banks northward to Cape Hatteras. By the summer (June – Aug.; 25.2°C to 30.8°C mean SST), turtles were fairly evenly dispersed along the entire survey range of the coast and Pamlico Sound, with only a few sightings in Core Sound. In the autumn (Sept. – Nov.; 9.6°C to 29.6°C mean SST), the majority of turtles sighted were along the coast and in eastern Pamlico Sound; however, fewer turtles were observed along the coast than in the summer. No turtles were seen during the winter surveys (Dec. – Feb.; 7.6°C to 11.2°C mean SST). The estimated mean surface density of turtles was highest along the coast in the summer of 2005 (0.615 turtles/km², SE = 0.220). In Core and Pamlico Sounds the highest mean surface density occurred during the autumn of 2005 (0.016 turtles/km², SE = 0.009). The mean seasonal abundance estimates were always highest in the coastal region, except in the winter when turtles were not sighted in either region. For Pamlico Sound, surface densities were always greater in the eastern than western section. The range of mean temperatures at which turtles were sighted was 9.68°C to 30.82°C. The majority of turtles sighted were within water ≥ 11°C. Dolphins were observed within estuarine waters and along the coast year-round; however, there were some general seasonal movements. In particular, during the summer sightings decreased along the coast and dolphins were distributed throughout Core and Pamlico Sounds, while in the winter the majority of dolphins were located along the coast and in southeastern Pamlico Sound. Although relative numbers changed seasonally between these areas, the estimated mean surface density of dolphins was highest along the coast in the spring of 2006 (9.564 dolphins/km², SE = 5.571). In Core and Pamlico Sounds the highest mean surface density occurred during the autumn of 2004 (0.192 dolphins/km², SE = 0.066). The estimated mean surface density of dolphins was lowest along the coast in the summer of 2004 (0.461 dolphins/km², SE = 0.294). The estimated mean surface density of dolphins was lowest in Core and Pamlico Sounds in the summer of 2005 (0.024 dolphins/km², SE = 0.011). In Pamlico Sound, estimated surface densities were greater in the eastern section except in the autumn. Dolphins were sighted throughout the entire range of mean SST (7.60°C to 30.82°C), with a tendency towards fewer dolphins sighted as water temperatures increased. Based on the findings of this study, sea turtles are most likely to be encountered within the OPAREAs when SST is ≥ 11°C. Since sea turtle distributions are generally limited by water temperature, knowing the SST of a given area is a useful predictor of sea turtle presence. Since dolphins were observed within estuarine waters year-round and throughout the entire range of mean SST’s, they likely could be encountered in the OPAREAs any time of the year. Although our findings indicated the greatest number of dolphins to be present in the winter and the least in the summer, their movements also may be related to other factors such as the availability of prey. (PDF contains 28 pages)

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This research is part of the Socioeconomic Research & Monitoring Program for the Florida Keys National Marine Sanctuary (FKNMS), which was initiated in 1998. In 1995-96, a baseline study on the knowledge, attitudes and perceptions of proposed FKNMS management strategies and regulations of commercial fishers, dive operators and on selected environmental group members was conducted by researchers at the University of Florida and the University of Miami’s Rosenstiel School of Atmospheric and Marine Science (RSMAS). The baseline study was funded by the U.S. Man and the Biosphere Program, and components of the study were published by Florida Sea Grant and in several peer reviewed journals. The study was accepted into the Socioeconomic Research & Monitoring Program at a workshop to design the program in 1998, and workshop participants recommended that the study be replicated every ten years. The 10-year replication was conducted in 2004-05 (commercial fishers) 2006 (dive operators) and 2007 (environmental group members) by the same researchers at RSMAS, while the University of Florida researchers were replaced by Thomas J. Murray & Associates, Inc., which conducted the commercial fishing panels in the FKNMS. The 10-year replication study was funded by NOAA’s Coral Reef Conservation Program. The study not only makes 10-year comparisons in the knowledge, attitudes and perceptions of FKNMS management strategies and regulations, but it also establishes new baselines for future monitoring efforts. Things change, and following the principles of “adaptive management”, management has responded with changes in the management plan strategies and regulations. Some of the management strategies and regulations that were being proposed at the time of the baseline 1995-96 study were changed before the management plan and regulations went into effect in July 1997. This was especially true for the main focus of the study which was the various types of marine zones in the draft and final zoning action plan. Some of the zones proposed were changed significantly and subsequently new zones have been created. This study includes 10-year comparisons of socioeconomic/demographic profiles of each user group; sources and usefulness of information; knowledge of purposes of FKNMS zones; perceived beneficiaries of the FKNMS zones; views on FKNMS processes to develop management strategies and regulations; views on FKNMS zone outcomes; views on FKNMS performance; and general support for FKNMS. In addition to new baseline information on FKNMS zones, new baseline information was developed for spatial use, investment and costs-and-earnings for commercial fishers and dive operators, and views on resource conditions for all three user groups. Statistical tests were done to detect significant changes in both the distribution of responses to questions and changes in mean scores for items replicated over the 10-year period. (PDF has 143 pages.)

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Final report on a three year study designed to investigate the effects of the Maryland hydraulic escalator clam dredge on populations and recruitment of the soft-shell clam, Mya arenaria. Experimental plots were established in the Potomac river, Maryland, and were dredged ina commerical manner by removing only legal size clams. quarterly samples were taken in the experimental and control plots by means of a van Veen grab for juvenile clams and the hydraulic dredge for older, deeper burrowing clams. Sediment samples were taken at selected periods for organic carbon and grain size analysis. Clams were separated into two size-groups. (PDF contains 38 pages)

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The purpose of the project is to improve our understanding about best management practices that can be utilized on diked managed wetlands in Suisun Marsh for reducing the occurrence of low dissolved oxygen (DO) and high methylmercury (MeHg) events associated primarily with fall flood-up practices. Low DO events are of concern because they can lead to undue stress and even mortality of sensitive aquatic organisms. Elevated MeHg levels are of concern because MeHg is a neurotoxin that bio-magnifies up the food chain and can cause deleterious effects to higher trophic level consumers such as piscivorous fish, birds, and mammals (including humans). This study involved two years (2007-2008) of intensive field data collection at two managed wetland sites in northwest Suisun Marsh and their surrounding tidal sloughs, an area with prior documented low DO events. In addition, the study collected limited soils and water quality field data and mapped vegetation for three managed wetland sites in the central interior of Suisun Marsh, for the purpose of examining whether wetlands at other locations exhibit characteristics that could indicate potential for similar concerns. In Year 1 of the study, the objective was to identify the baseline conditions in the managed wetlands and determine which physical management conditions could be modified for Year 2 to reduce low DO and MeHg production issues most effectively. The objective of Year 2 was to evaluate the effectiveness of these modified management actions at reducing production of low DO and elevated MeHg conditions within the managed wetlands and to continue improving understanding of the underlying biogeochemical processes at play. This Final Evaluation Memorandum examined a total of 19 BMPs, 14 involving modified water management operations and the remaining five involving modified soil and vegetation management practices. Some of these BMPs were previously employed and others have not yet been tested. For each BMP this report assesses its efficacy in improving water quality conditions and potential conflicts with wetland management. It makes recommendations for further study (either feasibility assessments or field testing) and whether to consider for future use. Certain previously used BMPs were found to be important contributors to poor water quality conditions and their continued use is not recommended. Some BMPs that could improve water quality conditions appear difficult to implement in regards to compatibility with wetland management; these BMPs require further elaboration and feasibility assessment to determine whether they should be field tested. In practice for any given wetland, there is likely a combination of BMPs that would together have the greatest potential to address the low DO and high MeHg water quality concerns. Consequently, this report makes no sweeping recommendations applicable to large groups of wetlands but instead promotes a careful consideration of factors at each wetland or small groups of wetlands and from that assessment to apply the most effective suite of BMPs. This report also identifies a number of recommended future actions and studies. These recommendations are geared toward improving the process understanding of factors that promote low DO and high MeHg conditions, the extent of these problems in Suisun Marsh, the regulatory basis for the DO standards for a large estuarine marsh, the economics of BMPs, and alternative approaches to BMPs on diked managed wetlands that may address the water quality issues. The most important of these recommendations is that future BMP implementation should be carried out within the context of rigorous scientific evaluation so as to gain the maximum improvement in how to manage these water quality issues in the diked managed wetlands of Suisun Marsh.

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This is the River Taw Salmon Action Plan Final document produced by the Environment Agency in 2000. This final Salmon Action Plan (SAP) for the River Taw catchment has been produced after consideration of feedback from external consultation. The SAP provides a list of the issues and actions which were agreed for a five-year programme to maintain and improve the River Taw salmon stock. Some of these actions have already been delivered before finalising the SAP, but others have yet to be addressed. An attempt has been made to estimate the cost of the actions, identify possible sources of funding and the timescale under which they will be dealt with. The Taw salmon stock is currently failing to meet its spawning target. However, there was a period of compliance in the 1990s following a decade of failure through the 1980s. The freshwater environment of the Taw has improved in recent years. The actions presented in this SAP are perceived as those that are required to address, as far as possible, the important issues and factors currently limiting the salmon stock on the river. This SAP aims to promote long term collaboration between the Agency and other interested parties in managing the River Taw salmon stock and fisheries.

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This is the River Torridge Salmon Action Plan Final document produced by the Environment Agency in 2000. This final Salmon Action Plan (SAP) for the River Torridge catchment has been produced after consideration of feedback from external consultation. The SAP provides a list of the issues and actions which were agreed for a five-year programme to maintain and improve the River Torridge salmon stock. Some of these actions have already been delivered before finalising the SAP, but others have yet to be addressed. An attempt has been made to estimate the cost of the actions, identify possible sources of funding and the timescale under which they will be dealt with. The Torridge salmon stock has declined dramatically since the 1960s and is currently failing to meet the spawning target. The decline in the spring fish component has accounted largely for the overall decrease in stocks. The reasons for the decline are not fully understood, but the spring fish problem is recognised as a national issue. The rate of survival over the marine phase has reduced in recent years for both the grilse and multi-sea winter (MSW) components. This is undoubtedly a contributory factor, which may now constrain stocks to lower levels than have existed historically. Agricultural pollution is recognised as one of the main factors limiting freshwater production. This SAP aims to promote long term collaboration between the Agency and other interested parties in managing the River Torridge salmon stock and fisheries.

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A two year, comprehensive, quantitative investigation was conducted to analyze and identify the spatial distribution of petrogenic and biogenic hydrocarbons in sediments, surface waters, fish and shellfish of Biscayne Bay, Florida. The goal for the first year of the project was to establish baseline information to support oil spill impact assessment and clean-up. One hundred fifty-five sediment and eleven biota samples were collected. The areas sampled included the Miami River, Intracoastal Waterway, tidal flats, access canals and environmentally sensitive shorelines. The second year of the study centered on areas exhibiting petroleum contamination. These areas included the Miami River, Little River, Goulds Canal, Black Creek and Military Canal. Surface and subsurface sediment, biota and surface water were collected. Sample collection, analyses, and data handling for the two year project were conducted so that all information was court-competent and scientifically accurate. Chain of custody was maintained for all samples. Total hydrocarbon content of surface sediments ranged from below detection limits to a high of 2663.44 pg/g. Several sample stations contained petroleum contamination. The majority of biota samples exhibited hydrocarbon concentrations and characteristics that indicated little, if any, petroleum contamination. Surface water samples ranged from 0.78 to 64.47 μg/L and several samples contained petroleum hydrocarbons. Our results indicate several areas of petroleum contamination. These areas are characterized by industrial complexes, port facilities, marinas, major boating routes and many of the major tributaries emptying into Biscayne Bay.

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Southeast Bering Sea Carrying Capacity (SEBSCC, 1996–2002) was a NOAA Coastal Ocean Program project that investigated the marine ecosystem of the southeastern Bering Sea. SEBSCC was co-managed by the University of Alaska Fairbanks, NOAA Alaska Fisheries Science Center, and NOAA Pacific Marine Environmental Laboratory. Project goals were to understand the changing physical environment and its relationship to the biota of the region, to relate that understanding to natural variations in year-class strength of walleye pollock (Theragra chalcogramma), and to improve the flow of ecosystem information to fishery managers. In addition to SEBSCC, the Inner Front study (1997–2000), supported by the National Science Foundation (Prolonged Production and Trophic Transfer to Predators: Processes at the Inner Front of the S.E. Bering Sea), was active in the southeastern Bering Sea from 1997 to 1999. The SEBSCC and Inner Front studies were complementary. SEBSCC focused on the middle and outer shelf. Inner Front worked the middle and inner shelf. Collaboration between investigators in the two programs was strong, and the joint results yielded a substantially increased understanding of the regional ecosystem. SEBSCC focused on four central scientific issues: (1) How does climate variability influence the marine ecosystem of the Bering Sea? (2) What determines the timing, amount, and fate of primary and secondary production? (3) How do oceanographic conditions on the shelf influence distributions of fish and other species? (4) What limits the growth of fish populations on the eastern Bering Sea shelf? Underlying these broad questions was a narrower focus on walleye pollock, particularly a desire to understand ecological factors that affect year-class strength and the ability to predict the potential of a year class at the earliest possible time. The Inner Front program focused on the role of the structural front between the well-mixed waters of the coastal domain and the two-layer system of the middle domain. Of special interest was the potential for prolonged post-spring-bloom production at the front and its role in supporting upper trophic level organisms such as juvenile pollock and seabirds. Of concern to both programs was the role of interannual and longer-term variability in marine climates and their effects on the function of sub-arctic marine ecosystems and their ability to support upper trophic level organisms.

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To develop an understanding of stock structure and recruitment variation in Bering Sea pollock, the Coastal Ocean Program of the National Oceanic and Atmospheric Administration (NOAA) funded an 7-year (1991-1997), interdisciplinary project named Bering Sea Fisheries-Oceanography Coordinated Investigations (BS FOCI; Schumacher and Kendall, 1995) for which NOAA and academic researchers were selected through a competitive process (Macklin, this report). The project goals, based on recommendations from an international symposium on pollock (Aron and Balsiger, 1989) were to (1) determine stock structure in the Bering Sea and its potential relationship to physical oceanography, and (2) examine recruitment processes in the eastern Bering Sea. Both of these have direct implication to management. An integrated set of field, laboratory, and modeling studies were established to accomplish these goals. To address the first goal, project objectives were to establish details of oceanic circulation relevant to larval dispersal and separation of stocks, and determine if unique chemical or genetic indicators existed for different stocks. The recruitment component of BS FOCI, addressing the second goal, focused on understanding causes of variable mortality of pollock larvae in the different habitats of the eastern Bering Sea. The emphasis of recruitment studies was to determine the dominant physical oceanographic features (turbulence, temperature, and transport) that could influence survival of pollock larvae, and investigate factors controlling food production for the larvae. A later component contrasted juvenile habitat in three hydrographic regimes around the Pribilof Islands (Brodeur, this report).

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A baseline survey for the project which had been conducted in 2009 had gaps that could not allow assessment of project performance in the outcome and impact indicators to be made. This study was, therefore, commissioned to reconstruct the baseline data, aligned to the impact and outcome indicators on the project logframe and results framework, against which project achievements could be assessed. The purpose and scope of the study was to reconstruct the baseline data and analysis describing the situation prior to QAFM Project inception, taking 2008 as the baseline year, which was aligned to the project logframe outcome and impact indicators; to collect data on current status to compare project outcome (and where possible impact) in improved fish handling sites in comparison with the baseline as well as with comparable non-improved fish landing sites as control group. The study was conducted through secondary data search from sources at NaFIRRI, DFR and ICEIDA. Field data collection was carried out using a sample survey covering 312 respondents including boat and gear owners, crew members, processors and traders at eight project and two control landing sites. Key Informant Interviews were conducted with DFOs and BMU leaders in the study districts and landing sites respectively.