83 resultados para 11-108
em Aquatic Commons
Resumo:
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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Cover [pdf, 1.2 Mb] PICES Science Board and Governing Council hold their first joint meeting [pp. 1-3] [pdf, 0.2 Mb] 3rd International Zooplankton Production Symposium [pp. 4-7] [pdf, 0.6 Mb] The state of the eastern North Pacific entering spring 2003 [pp. 8-9] [pdf, 0.4 Mb] The state of the western North Pacific in 2002 [pp. 10-13] [pdf, 0.6 Mb] The Bering Sea: Current status and recent events [pp. 14-15] [pdf. 0.7 Mb] Patricia Livingston [pp. 16-19] [pdf. 0.5 Mb] Recent changes in the abundance of northern anchovy (Engraulis mordax) off the Pacific Northwest, tracking a regime shift? [pp. 20-21] [pdf. 0.6 Mb] Developing new scientific programs in PICES [pp. 22-26] [pdf. 0.2 Mb] Report of the Yokohama 2003 MODEL Task Team Workshop to develop a marine ecosystem model of the North Pacific Ocean including pelagic fishes [pp. 27-29] [pdf. 0.5 Mb] 3rd PICES Workshop on the Okhotsk Sea and adjacent Areas [pp.30-31] [pdf. 0.4 Mb] Recent oceanographic and marine environmental studies at FERHRI [pp.32-34] [pdf. 0.4 Mb] Symposium Announcement [p. 35] [pdf. 0.3 Mb] PICES announcements [p. 36] [pdf. 0.3 Mb]
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Editorial and Contents The state of PICES science - 2002 Second annual Wooster Award to Yutaka Nagata Qingdao Open Science Meeting: A major landmark for GLOBEC GLOBEC OSM Session Highhlights PICES/GLOBEC Data Management Workshop PICES and GLOBEC modelling Some personal impressions of the GLOBEC OSM Photo highlights of PICES XI and GLOBEC OSM PICES Climate Change and Carrying Capacity (CCCC) Integration Workshop PICES/CLIVAR Workshop on Climate Variability in the Pacific and its impact on the marine ecosystem IGBP/SCOR Open Science Meeting on Ocean Biogeochemistry and Ecosystem Analysis Subarctic Ecosystem Response to Iron Enrichment Study (SERIES): eastern subarctic Pacific in July 2002 Introducing the GLOBEC International Project Office / GLOBEC Calendar 2003 Introducing the PICES Secretariat PICES Calendar
Resumo:
Proceedings of the Fifth Annual Meeting Agenda Report of Opening Session Report of Governing Council Meetings Reports of Science Board and Committees Science Board Working Group 5: Bering Sea (Final Report) Working Group 9: Subarctic Pacific Monitoring Report of the First Meeting Report of the Second Meeting Biological Oceanography Committee Working Group 11: Consumption of Marine Resources by Marine Birds and Mammals Fishery Science Committee Working Group 12: Crabs and Shrimps Marine Environmental Quality Committee Working Group 8: Practical Assessment Methodology Physical Oceanography and Climate Committee Working Group 10: Circulation and Ventilation in the Japan Sea /East Sea and its Adjacent Areas Technological Committee on Data Exchange Finance and Administration Report of Finance and Administration Committee Assets on 31st of December, 1995 Income and Expenditures for 1995 Budget for 1997 Composition of the Organization Officers, Delegates, Finance and Administration Committee, Science Board, Secretariat, Scientific and Technical Committees List of Participants List of Acronyms (Document has 163 pages.)
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*Table of Contents* Research & farming techniques Nursery rearing of Puntius goniotus: A preliminary trial K.N. Mohnta, J.K. Jena & S.N. Mohanty Artemia enrichment and biomass production for larval finfish and shellfish culture A.S. Ninawe Vembanad Lake: A potential spawner bank of the giant freshwater prawn Macrobrachium rosenbergii on the southwest coast of India Paramaraj Balamurugan, Pitchaimuthu Mariappan & Chellam Balasundaram Seed production of mud crab Scylla serrata at the Rajiv Gandhi Center for Aquaculture, Tamil Nadu, India Mohamed Shaji, Emilia T. Quinitio, Thampi Samraj, S. Kandan, K. Ganesh, Dinesh Kumar, S. Arulraj, S. Pandiarajan, Shajina Ismail and K. Dhandapan. Sustainable aquaculture Fish wastes in urban and suburban markets of Kolkata: Problems and potentials Kausik Mondal, Anilava Kaviraj & P.K. Mukhopadhyay People in aquaculture Peter Edwards writes on rural aquaculture: Farming carps in leased ponds by groups of poor women in Chandpur, Bangladesh Aquatic animal health Lymphocystis disease and diagnostic methods in China Jing Xing, Xiuzhen Sheng & Wenbin Zhan Asia-Pacific Marine Finfish Aquaculture Network Mesocosm technology advances grouper culture in northern Australia Elizabeth Cox, Peter Fry & Anjanette Johnston
Resumo:
Prosiguiendo con la política de rescatar documentos que, por diferentes motivos, se han extraviado con el paso del tiempo, el Programa para el estudio y uso sustentable de la biota austral (ProBiota) reedita el primer y único boletín de la Asociación Limnológica y Oceanográfica Argentina (ALOA). Esta asociación pretendía convocar a los hidrobiólogos argentinos, pero interrumpió su camino a poco de iniciado en el año 1953. Los motivos de ese hecho los desconozco; aunque personalmente creo que, entre otras cosas, debe haber influido el quiebre institucional de 1955 cuando se profundizaron nuevamente las heridas en nuestra sociedad. No deja de ser paradójico que hoy, a casi cincuenta años de este suceso, la Asociación Argentina de Limnología (AAL) se encuentre en una situación similar luego de veinte años de trayectoria que se cumplirían en el mes de marzo del próximo año. Hasta 1998, fecha de su último congreso, tuvo un gran impulso generando importantes eventos nacionales e internacionales. Sin embargo, a partir de allí fue decayendo con rapidez y hoy se enfrenta a su inminente disolución. A mi entender, la reversión de este hecho sólo podría lograrse sobre la base del sacrificio personal y del conjunto, solidaridad y, sobre todo, respeto a la memoria de todos aquellos que construyeron las bases de la limnología nacional.
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The paper presents: 1) biologic summaries for each of the formations for which paleontologic data are available, with brief discussions of the geologic age; 2) geologic correlations of the formations and the distribution of their age-equivalents in Central America, the West Indies, and the southeastern United States; 3) an outline of the paleogeography of middle America. The biologic summaries are based on the paleontologic memoirs in this vol. by Messars. Howe, Berry, Chuchman, Jackson, Canu and Bassler and Pilsbry, Miss Rathbun and myself.
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This technical memorandum documents the design, implementation, data preparation, and descriptive results for the 2006 Annual Economic Survey of Federal Gulf Shrimp Permit Holders. The data collection was designed by the NOAA Fisheries Southeast Fisheries Science Center Social Science Research Group to track the financial and economic status and performance by vessels holding a federal moratorium permit for harvesting shrimp in the Gulf of Mexico. A two page, self-administered mail survey collected total annual costs broken out into seven categories and auxiliary economic data. In May 2007, 580 vessels were randomly selected, stratified by state, from a preliminary population of 1,709 vessels with federal permits to shrimp in offshore waters of the Gulf of Mexico. The survey was implemented during the rest of 2007. After many reminder and verification phone calls, 509 surveys were deemed complete, for an ineligibility-adjusted response rate of 90.7%. The linking of each individual vessel’s cost data to its revenue data from a different data collection was imperfect, and hence the final number of observations used in the analyses is 484. Based on various measures and tests of validity throughout the technical memorandum, the quality of the data is high. The results are presented in a standardized table format, linking vessel characteristics and operations to simple balance sheet, cash flow, and income statements. In the text, results are discussed for the total fleet, the Gulf shrimp fleet, the active Gulf shrimp fleet, and the inactive Gulf shrimp fleet. Additional results for shrimp vessels grouped by state, by vessel characteristics, by landings volume, and by ownership structure are available in the appendices. The general conclusion of this report is that the financial and economic situation is bleak for the average vessels in most of the categories that were evaluated. With few exceptions, cash flow for the average vessel is positive while the net revenue from operations and the “profit” are negative. With negative net revenue from operations, the economic return for average shrimp vessels is less than zero. Only with the help of government payments does the average owner just about break even. In the short-term, this will discourage any new investments in the industry. The financial situation in 2006, especially if it endures over multiple years, also is economically unsustainable for the average established business. Vessels in the active and inactive Gulf shrimp fleet are, on average, 69 feet long, weigh 105 gross tons, are powered by 505 hp motor(s), and are 23 years old. Three-quarters of the vessels have steel hulls and 59% use a freezer for refrigeration. The average market value of these vessels was $175,149 in 2006, about a hundred-thousand dollars less than the average original purchase price. The outstanding loans averaged $91,955, leading to an average owner equity of $83,194. Based on the sample, 85% of the federally permitted Gulf shrimp fleet was actively shrimping in 2006. Of these 386 active Gulf shrimp vessels, just under half (46%) were owner-operated. On average, these vessels burned 52,931 gallons of fuel, landed 101,268 pounds of shrimp, and received $2.47 per pound of shrimp. Non-shrimp landings added less than 1% to cash flow, indicating that the federal Gulf shrimp fishery is very specialized. The average total cash outflow was $243,415 of which $108,775 was due to fuel expenses alone. The expenses for hired crew and captains were on average $54,866 which indicates the importance of the industry as a source of wage income. The resulting average net cash flow is $16,225 but has a large standard deviation. For the population of active Gulf shrimp vessels we can state with 95% certainty that the average net cash flow was between $9,500 and $23,000 in 2006. The median net cash flow was $11,843. Based on the income statement for active Gulf shrimp vessels, the average fixed costs accounted for just under a quarter of operating expenses (23.1%), labor costs for just over a quarter (25.3%), and the non-labor variable costs for just over half (51.6%). The fuel costs alone accounted for 42.9% of total operating expenses in 2006. It should be noted that the labor cost category in the income statement includes both the actual cash payments to hired labor and an estimate of the opportunity cost of owner-operators’ time spent as captain. The average labor contribution (as captain) of an owner-operator is estimated at about $19,800. The average net revenue from operations is negative $7,429, and is statistically different and less than zero in spite of a large standard deviation. The economic return to Gulf shrimping is negative 4%. Including non-operating activities, foremost an average government payment of $13,662, leads to an average loss before taxes of $907 for the vessel owners. The confidence interval of this value straddles zero, so we cannot reject, with 95% certainty, that the population average is zero. The average inactive Gulf shrimp vessel is generally of a smaller scale than the average active vessel. Inactive vessels are physically smaller, are valued much lower, and are less dependent on loans. Fixed costs account for nearly three quarters of the total operating expenses of $11,926, and only 6% of these vessels have hull insurance. With an average net cash flow of negative $7,537, the inactive Gulf shrimp fleet has a major liquidity problem. On average, net revenue from operations is negative $11,396, which amounts to a negative 15% economic return, and owners lose $9,381 on their vessels before taxes. To sustain such losses and especially to survive the negative cash flow, many of the owners must be subsidizing their shrimp vessels with the help of other income or wealth sources or are drawing down their equity. Active Gulf shrimp vessels in all states but Texas exhibited negative returns. The Alabama and Mississippi fleets have the highest assets (vessel values), on average, yet they generate zero cash flow and negative $32,224 net revenue from operations. Due to their high (loan) leverage ratio the negative 11% economic return is amplified into a negative 21% return on equity. In contrast, for Texas vessels, which actually have the highest leverage ratio among the states, a 1% economic return is amplified into a 13% return on equity. From a financial perspective, the average Florida and Louisiana vessels conform roughly to the overall average of the active Gulf shrimp fleet. It should be noted that these results are averages and hence hide the variation that clearly exists within all fleets and all categories. Although the financial situation for the average vessel is bleak, some vessels are profitable. (PDF contains 101 pages)
Resumo:
Executive Summary: This study describes the socio-economic characteristics of the U.S. Caribbean trap fishery that encompasses the Commonwealth of Puerto Rico and Territory of the U.S. Virgin Islands. In-person interviews were administered to one hundred randomly selected trap fishermen, constituting nearly 25% of the estimated population. The sample was stratified by geographic area and trap tier. The number of traps owned or fished to qualify for a given tier varied by island. In Puerto Rico, tier I consisted of fishermen who had between 1-40 fish traps, tier II was made up of fishermen who possessed between 41 and 100 fish traps, and tier III consisted of fishermen who held in excess of 100 fish traps. In St. Thomas and St. John, tier I was composed of fishermen who held between 1 and 50 fish traps, tier II consisted of fishermen who had between 51-150 fish traps and tier III was made up of fishermen who had in excess of 150 fish traps. Lastly, in St. Croix, tier I was made up of fishermen who had less than 20 fish traps and tier II consisted of fishermen who had 20 or more fish traps. The survey elicited information on household demographics, annual catch and revenue, trap usage, capital investment on vessels and equipment, fixed and variable costs, behavioral response to a hypothetical trap reduction program and the spatial distribution of traps. The study found that 79% of the sampled population was 40 years or older. The typical Crucian trap fisherman was older than their Puerto Rican and St. Thomian and St. Johnian counterparts. Crucian fishermen’s average age was 57 years whereas Puerto Rican fishermen’s average age was 51 years, and St. Thomian and St. Johnian fishermen’s average age was 48 years. As a group, St. Thomian and St. Johnian fishermen had 25 years of fishing experience, and Puerto Rican and Crucian fishermen had 30, and 29 years, respectively. Overall, 90% of the households had at least one dependent. The average number of dependents across islands was even, ranging between 2.8 in the district of St. Thomas and St. John and 3.4 in the district of St. Croix. The percentage utilization of catch for personal or family use was relatively low. Regionally, percentage use of catch for personal or family uses ranged from 2.5% in St. Croix to 3.8% in the St. Thomas and St. John. About 47% of the respondents had a high school degree. The majority of the respondents were highly dependent on commercial fishing for their household income. In St. Croix, commercial fishing made up 83% of the fishermen’s total household income, whereas in St. Thomas and St. John and Puerto Rico it contributed 74% and 68%, respectively. The contribution of fish traps to commercial fishing income ranged from 51% in the lowest trap tier in St. Thomas and St. John to 99% in the highest trap tier in St. Croix. On an island basis, the contribution of fish traps to fishing income was 75% in St. Croix, 61% in St. Thomas and St. John, and 59% in Puerto Rico. The value of fully rigged vessels ranged from $400 to $250,000. Over half of the fleet was worth $10,000 or less. The St. Thomas and St. John fleet reported the highest mean value, averaging $58,518. The Crucian and Puerto Rican fleets were considerably less valuable, averaging $19,831 and $8,652, respectively. The length of the vessels ranged from 14 to 40 feet. Fifty-nine percent of the sampled vessels were at least 23 feet in length. The average length of the St. Thomas and St. John fleet was 28 feet, whereas the fleets based in St. Croix and Puerto Rico averaged 21 feet. The engine’s propulsion ranged from 8 to 400 horsepower (hp). The mean engine power was 208 hp in St. Thomas and St. John, 108 hp in St. Croix, and 77 hp in Puerto Rico. Mechanical trap haulers and depth recorders were the most commonly used on-board equipment. About 55% of the sampled population reported owning mechanical trap haulers. In St. Thomas and St. John, 100% of the respondents had trap haulers compared to 52% in Puerto Rico and 20% in St. Croix. Forty-seven percent of the fishermen surveyed stated having depth recorders. Depth recorders were most common in the St. Thomas and St. John fleet (80%) and least common in the Puerto Rican fleet (37%). The limited presence of emergency position indication radio beacons (EPIRBS) and radar was the norm among the fish trap fleet. Only 8% of the respondents had EPIRBS and only 1% had radar. Interviewees stated that they fished between 1 and 350 fish traps. Puerto Rican respondents fished on average 39 fish traps, in contrast to St. Thomian and St. Johnian and Crucian respondents, who fished 94 and 27 fish traps, respectively. On average, Puerto Rican respondents fished 11 lobster traps, and St. Thomian and St. Johnian respondents fished 46 lobster traps. None of the Crucian respondents fished lobster traps. The number of fish traps built or purchased ranged between 0 and 175, and the number of lobster traps built or bought ranged between 0 and 200. Puerto Rican fishermen on average built or purchased 30 fish traps and 14 lobster traps, and St. Thomian and St. Johnian fishermen built or bought 30 fish traps and 11 lobster traps. Crucian fishermen built or bought 25 fish traps and no lobster traps. As a group, fish trap average life ranged between 1.3 and 5 years, and lobster traps lasted slightly longer, between 1.5 and 6 years. The study found that the chevron or arrowhead style was the most common trap design. Puerto Rican fishermen owned an average of 20 arrowhead traps. St. Thomian and St. Johnian and Crucian fishermen owned an average of 44 and 15 arrowhead fish traps, respectively. The second most popular trap design was the square trap style. Puerto Rican fishermen had an average of 9 square traps, whereas St. Thomian and St. Johnian fishermen had 33 traps and Crucian fishermen had 2 traps. Antillean Z (or S) -traps, rectangular and star traps were also used. Although Z (or S) -traps are considered the most productive trap design, fishermen prefer the smaller-sized arrowhead and square traps because they are easier and less expensive to build, and larger numbers of them can be safely deployed. The cost of a fish trap, complete with rope and buoys, varied significantly due to the wide range of construction materials utilized. On average, arrowhead traps commanded $94 in Puerto Rico, $251 in St. Thomas and St. John, and $119 in St. Croix. The number of trips per week ranged between 1 and 6. However, 72% of the respondents mentioned that they took two trips per week. On average, Puerto Rican fishermen took 2.1 trips per week, St. Thomian and St. Johnian fishermen took 1.4 trips per week, and Crucian fishermen took 2.5 trips per week. Most fishing trips started at dawn and finished early in the afternoon. Over 82% of the trips lasted 8 hours or less. On average, Puerto Rican fishermen hauled 27 fish traps per trip whereas St. Thomian and St. Johnian fishermen and Crucian fishermen hauled 68 and 26 fish traps per trip, respectively. The number of traps per string and soak time varied considerably across islands. In St. Croix, 84% of the respondents had a single trap per line, whereas in St. Thomas and St. John only 10% of the respondents had a single trap per line. Approximately, 43% of Puerto Rican fishermen used a single trap line. St. Thomian and St. Johnian fishermen soaked their traps for 6.9 days while Puerto Rican and Crucian fishermen soaked their traps for 5.7 and 3.6 days, respectively. The heterogeneity of the industry was also evidenced by the various economic surpluses generated. The survey illustrated that higher gross revenues did not necessarily translate into higher net revenues. Our analysis also showed that, on average, vessels in the trap fishery were able to cover their cash outlays, resulting in positive vessel income (i.e., financial profits). In Puerto Rico, annual financial profits ranged from $4,760 in the lowest trap tier to $32,467 in the highest tier, whereas in St. Thomas and St. John annual financial profits ranged from $3,744 in the lowest tier to $13,652 in the highest tier. In St. Croix, annual financial profits ranged between $9,229 and $15,781. The survey also showed that economic profits varied significantly across tiers. Economic profits measure residual income after deducting the remuneration required to keep the various factors of production in their existing employment. In Puerto Rico, annual economic profits ranged from ($9,339) in the lowest trap tier to $ 8,711 in the highest trap tier. In St. Thomas and St. John, annual economic profits ranged from ($7,920) in the highest tier to ($18,486) in the second highest tier. In St. Croix, annual economic profits ranged between ($7,453) to $10,674. The presence of positive financial profits and negative economic profits suggests that higher economic returns could be earned from a societal perspective by redirecting some of these scarce capital and human resources elsewhere in the economy. Furthermore, the presence of negative economic earnings is evidence that the fishery is overcapitalized and that steps need to be taken to ensure the long-run economic viability of the industry. The presence of positive financial returns provides managers with a window of opportunity to adopt policies that will strengthen the biological and economic performance of the fishery while minimizing any adverse impacts on local fishing communities. Finally, the document concludes by detailing how the costs and earnings information could be used to develop economic models that evaluate management proposals. (PDF contains 147 pages)
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This is the report of the “DoF/NACA-STREAM/FAO Workshop on Livelihoods Approaches and Analysis” that was conducted in Yangon, Union of Myanmar from 11-15 May 2004. The purpose of the workshop was to develop and document mechanisms for training in livelihoods approaches and analysis, and to build national capacity to conduct livelihoods studies. The workshop in Yangon was the first STREAM event in Myanmar, with colleagues coming to participate from Yangon and many Divisions and States throughout the country. The workshop in Yangon was the fourth in a series, the first of which was held in Iloilo City, Philippines, in November 2003, the second in Ranchi, India, in February 2004, and the third in Vientiane, Lao PDR in March 2004. A subsequent workshop will take place in Yunnan, China. The objectives of the workshop were to: Understand issues of interest to people whose livelihoods include aquatic resources management, especially those with limited resources Build “(national) livelihoods teams” to do livelihoods analyses and training, and share their experiences with communities and other stakeholders Share understandings of livelihoods approaches and analysis using participatory methods Review current NACA-STREAM livelihoods analysis documentation, adapt and supplement, towards the drafting of a Guide for Livelihoods Analysis Experience the use of participatory tools for livelihoods analysis Plan activities for carrying out livelihoods analyses, and Consider how to build capacity in monitoring and evaluation (M&E) and “significant change”. (Pdf contains 56 pages).
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Executive Summary: Tropical marine ecosystems in the Caribbean region are inextricably linked through the movement of pollutants, nutrients, diseases, and other stressors, which threaten to further degrade coral reef communities. The magnitude of change that is occurring within the region is considerable, and solutions will require investigating pros and cons of networks of marine protected areas (MPAs), cooperation of neighboring countries, improved understanding of how external stressors degrade local marine resources, and ameliorating those stressors. Connectivity can be broadly defined as the exchange of materials (e.g., nutrients and pollutants), organisms, and genes and can be divided into: 1) genetic or evolutionary connectivity that concerns the exchange of organisms and genes, 2) demographic connectivity, which is the exchange of individuals among local groups, and 3) oceanographic connectivity, which includes flow of materials and circulation patterns and variability that underpin much of all these exchanges. Presently, we understand little about connectivity at specific locations beyond model outputs, and yet we must manage MPAs with connectivity in mind. A key to successful MPA management is how to most effectively work with scientists to acquire the information managers need. Oceanography connectivity is poorly understood, and even less is known about the shape of the dispersal curve for most species. Dispersal kernels differ for various systems, species, and life histories and are likely highly variable in space and time. Furthermore, the implications of different dispersal kernels on population dynamics and management of species is unknown. However, small dispersal kernels are the norm - not the exception. Linking patterns of dispersal to management options is difficult given the present state of knowledge. The behavioral component of larval dispersal has a major impact on where larvae settle. Individual larval behavior and life history details are required to produce meaningful simulations of population connectivity. Biological inputs are critical determinants of dispersal outcomes beyond what can be gleaned from models of passive dispersal. There is considerable temporal and spatial variation to connectivity patterns. New models are increasingly being developed, but these must be validated to understand upstream-downstream neighborhoods, dispersal corridors, stepping stones, and source/sink dynamics. At present, models are mainly useful for providing generalities and generating hypotheses. Low-technology approaches such as drifter vials and oceanographic drogues are useful, affordable options for understanding local connectivity. The “silver bullet” approach to MPA design may not be possible for several reasons. Genetic connectivity studies reveal divergent population genetic structures despite similar larval life histories. Historical stochasticity in reproduction and/or recruitment likely has important, longlasting consequences on present day genetic structure. (PDF has 200 pages.)
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In September 2002, side scan sonar was used to image a portion of the sea floor in the northern OCNMS and was mosaiced at 1-meter pixel resolution using 100 kHz data collected at 300-meter range scale. Video from a remotely-operated vehicle (ROV), bathymetry data, sedimentary samples, and sonar mapping have been integrated to describe geological and biological aspects of habitat and polygon features have been created and attributed with a hierarchical deep-water marine benthic classification scheme (Greene et al. 1999). The data can be used with geographic information system (GIS) software for display, query, and analysis. Textural analysis of the sonar images provided a relatively automated method for delineating substrate into three broad classes representing soft, mixed sediment, and hard bottom. Microhabitat and presence of certain biologic attributes were also populated into the polygon features, but strictly limited to areas where video groundtruthing occurred. Further groundtruthing work in specific areas would improve confidence in the classified habitat map. (PDF contains 22 pages.)
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The First SPARK-STREAM Workshop on Livelihoods and Languages took place in Bangkok, Thailand, from 9-11 April 2003. It was the first activity in a SPARK-STREAM learning and communications process around livelihoods and languages. (PDF contains 53 pages)
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The swordfish, Xiphias gladius, is a large migratory oceanic species. It is widely distributed in tropical, temperate, and sometimes cold waters of all oceans, and is usually found in areas with sea-surface temperatures above 13°C. It can reach a maximum size of 540 kg, and is a favorite food fish in many countries. It is excellent for steaks, canning, or teriyaki, the Japanese dish of meat grilled with sugar, soy sauce, and rice wine. Swordfish is harvested commercially throughout its distribution, in both coastal and high-seas fisheries. Sport fisheries for swordfish are very small compared to those for other billfishes, accounting for no more than a few hundred fish per year. (PDF file contains 284 pages.)