409 resultados para Borderlands -- California, Southern
Resumo:
ENGLISH: The map method, the Jones method, the variance-covariance method, and the Skellam method were used to study the migrations of tagged yellowfin tuna released off the southern coast of Mexico in 1960 and 1969. The first three methods are all useful, and each presents information which is complementary to that presented by the others. The Skellam method, as used in this report, is less useful. The movements of the tagged fish released in 1960 appeared to have been strongly directed, but this was probably caused principally by the distribution of the fishing effort. The effort was much more widely distributed in 1970, and the movements of the fish released in 1969 appeared to have been much less directed. The correlation coefficients derived from the variance-covariance method showed that it was not random, however. The small fish released in the Acapulco and 10°N-100°W areas in 1969 migrated to the Manzanillo area near the beginning of February 1970. The medium and large fish released in the same areas in the same year tended to migrate to the southeast throughout the first half of 1970, however. SPANISH: El método de mapas, el de Jones, el de la variancia-covariancia y el de Skellam fueron empleados para estudiar las migraciones del atún aleta amarilla marcado y liberado frente a la costa meridional de México en 1960 y 1969. Los tres primeros métodos son todos útiles, y cada uno presenta información que complementa la presentada por los otros. El método de Skellam, conforme se usa en este informe, es menos útil. Parece que los desplazamientos de los peces marcados y liberados en 1960 hubieran sido fuertemente orientados, pero ésto probablemente fue causado principalmente por la distribución del esfuerzo de pesca. El esfuerzo se distribuyó más extensamente en 1970, y parece que los desplazamientos de los peces liberados en 1969 fueran menos orientados. Los coeficientes de correlación derivados del método variancia-covariancia indicaron, sin embargo, que no eran aleatorios. Los peces pequeños liberados en las áreas de Acapulco y los 10°N-100°W en 1969 migraron al área de Manzanillo a principios de febrero 1970. Los peces medianos y grandes liberados en las mismas áreas en el mismo año tuvieron, sin embargo, la tendencia a desplazarse al sudeste durante el primer semestre de 1970. (PDF contains 64 pages.)
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The Alliance for Coastal Technologies (ACT) Workshop on Towed Vehicles: Undulating Platforms As Tools for Mapping Coastal Processes and Water Quality Assessment was convened February 5-7,2007 at The Embassy Suites Hotel, Seaside, California and sponsored by the ACT-Pacific Coast partnership at the Moss Landing Marine Laboratories (MLML). The TUV workshop was co-chaired by Richard Burt (Chelsea Technology Group) and Stewart Lamerdin (MLML Marine Operations). Invited participants were selected to provide a uniform representation of the academic researchers, private sector product developers, and existing and potential data product users from the resource management community to enable development of broad consensus opinions on the application of TUV platforms in coastal resource assessment and management. The workshop was organized to address recognized limitations of point-based monitoring programs, which, while providing valuable data, are incapable of describing the spatial heterogeneity and the extent of features distributed in the bulk solution. This is particularly true as surveys approach the coastal zone where tidal and estuarine influences result in spatially and temporally heterogeneous water masses and entrained biological components. Aerial or satellite based remote sensing can provide an assessment of the aerial extent of plumes and blooms, yet provide no information regarding the third dimension of these features. Towed vehicles offer a cost-effective solution to this problem by providing platforms, which can sample in the horizontal, vertical, and time-based domains. Towed undulating vehicles (henceforth TUVs) represent useful platforms for event-response characterization. This workshop reviewed the current status of towed vehicle technology focusing on limitations of depth, data telemetry, instrument power demands, and ship requirements in an attempt to identify means to incorporate such technology more routinely in monitoring and event-response programs. Specifically, the participants were charged to address the following: (1) Summarize the state of the art in TUV technologies; (2) Identify how TUV platforms are used and how they can assist coastal managers in fulfilling their regulatory and management responsibilities; (3) Identify barriers and challenges to the application of TUV technologies in management and research activities, and (4) Recommend a series of community actions to overcome identified barriers and challenges. A series of plenary presentation were provided to enhance subsequent breakout discussions by the participants. Dave Nelson (University of Rhode Island) provided extensive summaries and real-world assessment of the operational features of a variety of TUV platforms available in the UNOLs scientific fleet. Dr. Burke Hales (Oregon State University) described the modification of TUV to provide a novel sampling platform for high resolution mapping of chemical distributions in near real time. Dr. Sonia Batten (Sir Alister Hardy Foundation for Ocean Sciences) provided an overview on the deployment of specialized towed vehicles equipped with rugged continuous plankton recorders on ships of opportunity to obtain long-term, basin wide surveys of zooplankton community structure, enhancing our understanding of trends in secondary production in the upper ocean. [PDF contains 32 pages]
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The Alliance for Coastal Technologies (ACT) Workshop on Optical Remote Sensing of Coastal Habitats was convened January 9-11, 2006 at Moss Landing Marine Laboratories in Moss Landing, California, sponsored by the ACT West Coast regional partnership comprised of the Moss Landing Marine Laboratories (MLML) and the Monterey Bay Aquarium Research Institute (MBARI). The "Optical Remote Sensing of Coastal Habitats" (ORS) Workshop completes ACT'S Remote Sensing Technology series by building upon the success of ACT'S West Coast Regional Partner Workshop "Acoustic Remote Sensing Technologies for Coastal Imaging and Resource Assessment" (ACT 04-07). Drs. Paul Bissett of the Florida Environmental Research Institute (FERI) and Scott McClean of Satlantic, Inc. were the ORS workshop co-chairs. Invited participants were selected to provide a uniform representation of the academic researchers, private sector product developers, and existing and potential data product users from the resource management community to enable development of broad consensus opinions on the role of ORS technologies in coastal resource assessment and management. The workshop was organized to examine the current state of multi- and hyper-spectral imaging technologies with the intent to assess the current limits on their routine application for habitat classification and resource monitoring of coastal watersheds, nearshore shallow water environments, and adjacent optically deep waters. Breakout discussions focused on the capabilities, advantages ,and limitations of the different technologies (e.g., spectral & spatial resolution), as well as practical issues related to instrument and platform availability, reliability, hardware, software, and technical skill levels required to exploit the data products generated by these instruments. Specifically, the participants were charged to address the following: (1) Identify the types of ORS data products currently used for coastal resource assessment and how they can assist coastal managers in fulfilling their regulatory and management responsibilities; (2) Identify barriers and challenges to the application of ORS technologies in management and research activities; (3) Recommend a series of community actions to overcome identified barriers and challenges. Plenary presentations by Drs. Curtiss 0. Davis (Oregon State University) and Stephan Lataille (ITRES Research, Ltd.) provided background summaries on the varieties of ORS technologies available, deployment platform options, and tradeoffs for application of ORS data products with specific applications to the assessment of coastal zone water quality and habitat characterization. Dr. Jim Aiken (CASIX) described how multiscale ground-truth measurements were essential for developing robust assessment of modeled biogeochemical interpretations derived from optically based earth observation data sets. While continuing improvements in sensor spectral resolution, signal to noise and dynamic range coupled with sensor-integrated GPS, improved processing algorithms for georectification, and atmospheric correction have made ORS data products invaluable synoptic tools for oceanographic research, their adoption as management tools has lagged. Seth Blitch (Apalachicola National Estuarine Research Reserve) described the obvious needs for, yet substantial challenges hindering the adoption of advanced spectroscopic imaging data products to supplement the current dominance of digital ortho-quad imagery by the resource management community, especially when they impinge on regulatory issues. (pdf contains 32 pages)
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The Alliance for Coastal Technologies (ACT) Workshop on Trace Metal Sensors for Coastal Monitoring was convened April 11-13, 2005 at the Embassy Suites in Seaside, California with partnership from Moss Landing Marine Laboratories (MLML) and the Monterey Bay Aquarium Research Institute (MBARI). Trace metals play many important roles in marine ecosystems. Due to their extreme toxicity, the effects of copper, cadmium and certain organo-metallinc compounds (such as tributyltin and methylmercury) have received much attention. Lately, the sublethal effects of metals on phytoplankton biochemistry, and in some cases the expression of neurotoxins (Domoic acid), have been shown to be important environmental forcing functions determining the composition and gene expression in some groups. More recently the role of iron in controlling phytoplankton growth has led to an understanding of trace metal limitation in coastal systems. Although metals play an important role at many different levels, few technologies exist to provide rapid assessment of metal concentrations or metal speciation in the coastal zone where metal-induced toxicity or potential stimulation of harmful algal blooms, can have major economic impacts. This workshop focused on the state of on-site and in situ trace element detection technologies, in terms of what is currently working well and what is needed to effectively inform coastal zone managers, as well as guide adaptive scientific sampling of the coastal zone. Specifically the goals of this workshop were to: 1) summarize current regional requirements and future targets for metal monitoring in freshwater, estuarine and coastal environments; 2) evaluate the current status of metal sensors and possibilities for leveraging emerging technologies for expanding detection limits and target elements; and 3) help identify critical steps needed for and limits to operational deployment of metal sensors as part of routine water quality monitoring efforts. Following a series of breakout group discussions and overview talks on metal monitoring regulatory issues, analytical techniques and market requirements, workshop participants made several recommendations for steps needed to foster development of in situ metal monitoring capacities: 1. Increase scientific and public awareness of metals of environmental and biological concern and their impacts in aquatic environments. Inform scientific and public communities regarding actual levels of trace metals in natural and perturbed systems. 2. Identify multiple use applications (e.g., industrial waste steam and drinking water quality monitoring) to support investments in metal sensor development. (pdf contains 27 pages)
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Elkhorn Slough was first exposed to direct tidal forcing from the waters of Monterey Bay with the construction of Moss Landing Harbor in 1946. Elkhorn Slough is located mid-way between Santa Cruz and Monterey close to the head of Monterey Submarine Canyon. It follows a 10 km circuitous path inland from its entrance at Moss Landing Harbor. Today, Elkhorn Slough is a habitat and sanctuary for a wide variety of marine mammals, fish, and seabirds. The Slough also serves as a sink and pathway for various nutrients and pollutants. These attributes are directly or indirectly affected by its circulation and physical properties. Currents, tides and physical properties of Elkhorn Slough have been observed on an irregular basis since 1970. Based on these observations, the physical characteristics of Elkhorn Slough are examined and summarized. Elkhorn Slough is an ebb-dominated estuary and, as a result, the rise and fall of the tides is asymmetric. The fact that lower low water always follows higher high water and the tidal asymmetry produces ebb currents that are stronger than flooding currents. The presence of extensive mud flats and Salicornia marsh contribute to tidal distortion. Tidal distortion also produces several shallow water constituents including the M3, M4, and M6 overtides and the 2MK3 and MK3 compound tides. Tidal elevations and currents are approximately in quadrature; thus, the tides in Elkhorn Slough have some of the characters of a standing wave system. The temperature and salinity of lower Elkhorn Slough waters reflect, to a large extent, the influence of Monterey Bay waters, whereas the temperature and salinity of the waters of the upper Slough (>5 km from the mouth) are more sensitive to local processes. During the summer, temperature and salinity are higher in the upper slough due to local heating and evaporation. Maximum tidal currents in Elkhorn Slough have increased from approximately 75 to 120 cm/s over the past 30 years. This increase in current speed is primarily due to the change in tidal prism which has increased from approximately 2.5 to 6.2 x 106 m3 between 1956 and 1993. The increase in tidal prism is the result of both 3 rapid man-made changes to the Slough, and the continuing process of tidal erosion. Because of the increase in the tidal prism, the currents in Elkhorn Slough exhibit positive feedback, a process with uncertain consequences. [PDF contains 55 pages]
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Daily sea surface temperatures have been acquired at the Hopkins Marine Station in Pacific Grove, California since January 20, 1919.This time series is one of the longest oceanographic records along the U.S. west coast. Because of its length it is well-suited for studying climate-related and oceanic variability on interannual, decadal, and interdecadal time scales. The record, however, is not homogeneous, has numerous gaps, contains possible outliers, and the observations were not always collected at the same time each day. Because of these problems we have undertaken the task of reconstructing this long and unique series. We describe the steps that were taken and the methods that were used in this reconstruction. Although the methods employed are basic, we believe that they are consistent with the quality of the data. The reconstructed record has values at every time point, original, or estimated, and has been adjusted for time-of-day variations where this information was available. Possible outliers have also been examined and replaced where their credibility could not be established. Many of the studies that have employed the Hopkins time series have not discussed the issue of data quality and how these problems were addressed. Because of growing interest in this record, it is important that a single, well-documented version be adopted, so that the results of future analyses can be directly compared. Although additional work may be done to further improve the quality of this record, it is now available via the internet. [PDF contains 48 pages]
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ENGLISH: Totals of 59,547 tagged yellowfin and 90,412 tagged skipjack were released during 1952-1964 throughout the range of the fishery in the eastern Pacific Ocean during that period. Most of the fish were released from commercial baitboats, either on regular fishing trips or on chartered trips to catch fish for tagging. There we re 8,397 yellowfin and 4,381 skipjack returned from these releases. There appear to be two main groups of yellowfin in the eastern Pacific Ocean. There is considerable intermingling among the fish of the two groups, however. The fish of the northern group (west coast of Baja California, Gulf of California, and Revillagigedo Islands) first appear in the Revillagigedo Islands in about April, and migrate north along the Baja California coast during the spring and summer and south along that coast during the fall. Recruits to the southern group (Tres Marias Islands to northern Chile) appear at many points or continuously along most of the coast. The fish which first appear in the northern Panama Bight in April migrate rapidly northwest to Central America and Mexico and south to the Gulf of Guayaquil. There also appear to be two main groups of skipjack in the eastern Pacific Ocean. The fish of the northern group (west coast of Baja California, Gulf of California, and Revillagigedo Islands ) perform about the same migration as do the yellowfin of the same area, but most of the skipjack apparently then migrate to the central Pacific Ocean during the fall and/or winter. Recruits to the southern group (Central America to northern Chile) appear mostly in or near the Panama Bight. The fish which first appear in the northern Panama Bight in April migrate rapidly northwest to Central America and south to the Gulf of Guayaquil. The proportions which migrate in these directions vary considerably from year to year, this perhaps being dependent on differences in the sea-surface temperatures. SPANISH: Durante el período de 1952-1964 se liberó a través de todos los límites de distribución de la pesquería en el Océano Pacífico oriental un total de 59,547 aleta amarilla y 90,412 barriletes marcados. La mayoria de los peces fueron liberados de barcos de carnada comerciales, o en viajes regulares de pesca o en viajes en los que se fletaron los barcos para capturar atunes y marcarlos. De estas líberaciones se recapturaron 8,397 aleta amarilla y 4,381 barriletes. Parece que haya dos grupos principales de aleta amarilla en el Océano Pacífico oriental. Sin embargo, existe una entremezcla considerable entre los peces de los dos grupos. Los peces del grupo septentrional (costa occidental de Baja California, Golfo de California y Islas Revillagigedo) aparecen primero en las Islas Revillagigedo alrededor de abril, y durante la primavera y el verano se desplazan al norte a lo largo de la costa de Baja California y durante el otoño al sur a lo largo de la costa. Los reclutas del grupo meridional (Islas Tres Marias hasta el norte de Chile) aparecen en muchas partes o continuamente a lo largo de la mayoría de la costa. Los peces que aparecen primero en la región septentrional del Panamá Bight en abril se desplazan rápidamente al noroeste a la América Central y México y al sur al Golfo de Guayaquil. Parece también que existen dos grupos principales de barrilete en el Océano Pacífico oriental. Los peces del gr upo septentrional (costa occidental de Baja California, Golfo de California e Islas Revillagigedo ) realizan casi la misma migración que el atún aleta amarilla de la misma área, pero aparentemente la mayor parte del barrilete se desplaza luego al Océano Pacífico central durante el otoño y/o en el invierno. Los reclutas al grupo meridional (América Central al norte de Chile) aparecen en su mayoría en el Panamá Bight o cerca a este lugar. Los peces que aparecen primero en la región septentrional del Panamá Bight en abril se desplazan rápidamente al noroeste a la América Central y al sur al Golfo de Guayaquil. Las proporciones que se desplazan en estas direcciones varían considerablemente de año a año; tal vez esto depende en las diferencias de temperatura de la superficie del mar. (PDF contains 227 pages.)
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Phosphorus removal by wetlands and basins in Lake Tahoe may be improved through designing these systems to filter storm water through media having higher phosphorus removal capabilities than local parent material. Substrates rich in iron, aluminum and calcium oftentimes have enhanced phosphorus removal. These substrates can be naturally occurring, byproducts of industrial or water treatment processes, or engineered. Phosphorus removal fundamentally occurs through chemical adsorption and/or precipitation and much of the phosphorus can be irreversibly bound. In addition to these standard media, other engineered substrates are available to enhance P removal. One such substrate is locally available in Reno and uses lanthanum coated diatomaceous earth for arsenate removal. This material, which has a high positive surface charge, can also irreversibly remove phosphorus. Physical factors also affect P removal. Specifically, specific surface area and particle shape affect filtration capacity, contact area between water and the surface area, and likelihood of clogging and blinding. A number of substrates have been shown to effectively remove P in case studies. Based upon these studies, promising substrates include WTRs, blast furnace slag, steel furnace slag, OPC, calcite, marble Utelite and other LWAs, zeolite and shale. However, other nonperformance factors such as environmental considerations, application logistics, costs, and potential for cementification narrow the list of possible media for application at Tahoe. Industrial byproducts such as slags risk possible leaching of heavy metals and this potential cannot be easily predicted. Fly ash and other fine particle substrates would be more difficult to apply because they would need to be blended, making them less desirable and more costly to apply than larger diameter media. High transportation costs rule out non-local products. Finally, amorphous calcium products will eventually cementify reducing their effectiveness in filtration systems. Based upon these considerations, bauxite, LWAs and expanded shales/clays, iron-rich sands, activated alumina, marble and dolomite, and natural and lanthanum activated diatomaceous earth are the products most likely to be tested for application at Tahoe. These materials are typically iron, calcium or aluminum based; many have a high specific surface area; and all have low transportation costs. (PDF contains 21 pages)
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The Zanzibar Workshop Proceedings consists of the report and the Statement of the Workshop and provides a rich understanding of the dynamics of traditional, indigenous, small-scale and artisanal fisheries and fishing communities in the Eastern and Southern African (ESA) context. The issues covered include: the saga of rights denied to coastal lands, fishing, and threats to livelihood arising from lack of recognition of traditional rights and the livelihood needs of people in the region; the aspirations of coastal and inland communities to maintain or improve their livelihoods; and a bottom-up perspective on access rights to fishing, post-harvest rights and economic and social rights. This report will be a valuable source of information for community organizers, trade union leaders, government officials and the donor community, including multilateral organizations, researchers and for all those who are interested in the well-being of ESA fishing communities.
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ENGLISH: In May 1971, a joint united states - Mexican experiment, Project Little Window 2, (LW-2) involving data collected by satellite, aircraft and ship sensors was made in the southern part of the Gulf of California. LW-2 was planned as an improved and enlarged version of LW-l (conducted the previous year; Stevenson and Miller, 1971) with field work scheduled to be made within a 200 by 200 km square region in the Gulf of California. The purposes of the new field study were to determine through coordinated measurements from ships, aircraft and satellites, the utility of weather satellites to measure surface temperature features of the ocean from space and specifically to evaluate the high resolution infrared sensors aboard N~ 1, ITOS 1 and NIMBUS 4 and to estimate the magnitude of the atmospheric correction factors needed to bring the data from the spacecraft sensors into agreement with surface measurements. Due to technical problems during LW-2, however, useful data could not be obtained from ITOS 1 and NIMBUS 4 so satellite information from only NOAA-1 was available for comparison. In addition, a new purpose was added, i.e., to determine the feasibility of using an Automatic picture Transmission (APT) receiver on shore and at sea to obtain good quality infrared data for the local region. SPANISH: En mayo 1971, los Estados Unidos y México realizaron un experimento en conjunto, Proyecto Little Window 2 (LW-2), en el que se incluyen datos obtenidos mediante captadores de satélites, aviones y barcos en la parte meridional del Golfo de California. Se planeó LW-2 para mejorar y ampliar el proyecto de LW-l (conducido el año anterior; Stevenson y Miller, 1971), realizándose el trabajo experimental en una región de 200 por 200 km cuadrados, en el Golfo de California. El objeto de este nuevo estudio experimental fue determinar mediante reconocimientos coordinados de barcos, aviones y satélites la conveniencia de los satélites meteorológicos para averiguar las características de la temperatura superficial del océano desde el espacio, y especialmente, evaluar los captadores infrarrojos de alta resolución a bordo de NOAA 1, ITOS 1 Y NIMBUS 4, y estimar la magnitud de los factores de corrección atmosféricos necesarios para corregir los datos de los captadores espaciales para que concuerden con los registros de la superficie. Sin embargo, debido a problemas técnicos durante LW-2, no fue posible obtener datos adecuados de ITOS 1 y NIMBUS 4, as1 que solo se pudo disponer de la información de NOAA 1 para hacer las comparaciones. Además se quiso determinar la posibilidad de usar un receptor de Trasmisión Automático de Fotografias (APT) en el mar para obtener datos infarojos de buena calidad en la región local. (PDF contains 525 pages.)
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Regulatory action to protect California’s coastal water quality from degradation by copper from recreational boats’ antifouling paints interacts with efforts to prevent transport of invasive, hull-fouling species. A copper regulatory program is in place for a major yacht basin in northern San Diego Bay and in process for other major, California boat basins. “Companion” fouling control strategies are used with copper-based antifouling paints, as some invasive species have developed resistance to the copper biocide. Such strategies are critical for boats with less toxic or nontoxic hull coatings. Boat traffic along over 3,000 miles of coastline in California and Baja California increases invasive species transport risks. For example, 80% of boats in Baja California marinas are from the United States, especially California. Policy makers, boating businesses and boat owners need information on costs and supply-side capacity for effective fouling control measures to co-manage water quality and invasive species concerns. (PDF contains 3 pages)
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Generally, wetlands are thought to perform water purification functions, removing contaminants as water flows through sediment and vegetation. This paradigm was challenged when Grant et al. (2001) reported that Talbert Salt Marsh (Figure 1.) increased fecal indicator bacteria (FIB) output to coastal waters, contributing to poor coastal water quality. Like most southern California wetlands, Talbert Salt Marsh has been severely degraded. It is a small (10 ha), restored wetland, only 1/100th its original size, and located at the base of a highly urbanized watershed. Is it reasonable to expect that this or any severely altered wetland will perform the same water purification benefits as a natural wetland? To determine how a more pristine southern California coastal wetland attenuated bacterial contaminants, we investigated FIB concentrations entering and exiting Carpinteria Salt Marsh (Figure 2.), a 93 ha, moderate-sized, relatively natural wetland.(PDF contains 4 pages)
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Questionnaires containing 39 questions were prepared and administered to 50 women in ten fishing villages in the Southern Kainji Lake Basin to assess the level of women participation in fisheries activities. Results showed that 100% of the women interviewed were involved in fisheries activities and the following factors were considered. Age group between 20-30 years was 18%; 31-40 years; 30%; and above 40 years had the highest percentage of 40%. Also 98% of the women involve in fisheries activities were married while only 2% were not married. Muslin women constituted 82% while 18% were Christians. About 70% of Hausas were involved: no Igbos and Yorubas, while 30% were other tribes, which included Ijaws, Isokos and Urohobos. The percentage of women without education amounted to 62%, those women with Koranic education accounted for 22%, 14% had primary education while only 2% had secondary education. Few women were directly involved in fishing and statistical analysis showed that there was insignificant difference from village to village. All the women (100%) were involved in fish processing and storage (preservation) before sale. Only 26% of the women were not involved in fish marketing. Also 26% of the women made profits ranging from N500 to N1,000 per week, 24% make N1,000 to N1,500 per week, 12% made N1,500 to N2,000 and 38% made profit above N2,000. Statistical analysis showed that there was a significant difference in the profit made by the women (P<0.05) from the foregoing, women were actively involved in all fisheries activities
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This study examines how Thailand’s biodiversity conservation measures affect fishing communities, especially in the marine protected areas (MPAs) on the Andaman Sea coastline. It documents the various efforts of the local fishing communities to protect the resources in the area. Also included are recommendations for government agencies, civil society and the international community. [PDF contains 94 pages]
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The objective of this article is to review the populations of Arctic charr in the south of Scotland which have become locally extinct, and the reasons for their demise. In the British Isles, the Arctic charr in individual lakes have been isolated from each other for thousands of years and have developed a variety of phenotypic characteristics which are probably genetically based. About 200 populations of Arctic charr have been recorded from different parts of the British Isles: approximately 12 in England, 50 in Ireland, 175 in Scotland and four in Wales. The threats to charr from acidification, afforestation, engineering schemes, angling and fish farming are assessed, and the establishment of new populations is proposed as a method of replacing extinct stocks or providing an additional safeguard for valuable stocks in threatened waters.