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(Document pdf contains 54 pages)

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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)

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Fish were collected weekly in Biscayne Bay using a monofilament gill net set from a small skiff during 20-30 minute intervals. Although weekly sampling took place for 2.5 years, only the data from samples collected from June 1976 to June 1977 were used in this document. Abnormal external conditions of fins and body were observed on each fish and recorded. Fish were returned immediately to their habitats. Fish collected in the time period for this study numbered 3,765 and included 32 species. Of these, 16 species, totaling 3,556 fish, were caught in sufficient numbers (20 or more) to warrant data analysis. Only 3 of the 16 species could be considered relatively unafflicted: Aetobatus narinari (spotted eagle ray), Diodon hystrix (porcupinefish), and Selene vomer (lookdown). More than 80% of the examined specimens of these three species were unaffected. Less than 20% of the specimens of Diapterus plumieri (striped mojarra), Micropogonias undulatus (Atlantic croaker), and Pogonias cromis (black drum) displayed normal conditions. The three most afflicted species were Diapterus plumieri, striped mojarra; Micropogonias undulatus, Atlantic croaker; and Pogonias cromis, black drum. Only 7, 3, and 7% respectively showed no external evidence of disease. Data described in this document were originally tabulated in the mid-1970s, remained unpublished, and are no longer available. This document was based on archived unpublished text, a data summary table, and figures. Most of the text and cited references were the ones used in the original manuscript and no attempt was made to update them. (PDF contains 44 pages)

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This report provides an assessment of recent investigations into endocrine disruption in fresh and saltwater species of fish. Most work to date has concen-trated on reproductive endocrine disruption. Laboratory studies have shown a variety of synthetic and natural chemicals including certain industrial intermediates, PAHs, PCBs, pesticides, dioxins, trace elements and plant sterols can interfere with the endocrine system in fish. The potency of most of these chemicals, however, is typically hundreds to thousands of times less than that of endog-enous hormones. Evidence of environmental endocrine disruption ranges from the presence of female egg proteins in males and reduced levels of endogenous hormones in both males and females, to gonadal histopathologies and intersex (presence of ovotestes) fish. Overt endocrine disruption in fish does not appear to be a ubiquitous environmental phenomenon, but rather more likely to occur near sewage treatment plants, pulp and paper mills, and in areas of high organic chemical contamination. However, more wide-spread endocrine disruption can occur in rivers with smaller flows and correspondingly large or numerous wastewater inputs. Some of the most severe examples of endocrine disruption in fish have been found adjacent to sewage treatment plants. Effects are thought to be caused prima-rily by natural and synthetic estrogens and to a lesser extent by the degradation products of alkylphenol poly-ethoxylate surfactants. Effects found in fish near pulp and paper mills include reduced levels of estrogens and androgens as well as masculinization of females, and has been linked to the presence of β-sitosterol, a plant sterol. Effects seen in areas of heavy industrial activity typically include depressed levels of estrogens and androgens as well as reduced gonadal growth, and may be linked to the presence of PAHs, PCBs, and possibly dioxins. At this time, however, there is no clear indication that large populations of fish are being seriously impacted as a result of endocrine disruption, although additional work is needed to address this possibility. (PDF contains 63 pages)

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ENGLISH: 1. Quantitative phytoplankton samples were collected by the Inter-American Tropical Tuna Commission at the surface and ten meters in the Gulf of Panama, as follows: a) 18-21 March, 1958 (31 stations)-during the height of the upwelling season, b) 10-12 July, 1957 (10 stations)-during the transition to the rainy season at a time when mild upwelling winds reappear, c) 7-8 November, 1957 (15 stations)-during the height of the rainy season. 2. Maximum phytoplankton populations occurred during the upwelling season, followed by a considerable decline during July, and a further Subsidence during November. 3. A remarkable regional uniformity in species composition was observed during the surveys despite regional differences in growth conditions. Diatoms overwhelmingly dominated the communities. 4. During all surveys, the innermost regions, generally north of 8°30'N, were the most productive. The least productive areas were in the offing of San Miguel Bay and Parita Bay, suggesting that nutrient accretion via runoff is inadequate to sustain sizeable autotrophic plant populations in those regions. 5. During all surveys, phytoplankton growth appeared to be limited by nutrient availability. 6. During all surveys, phytoplankton growth appeared to be related to depth of the water column. 7. Although below average rainfall contributed to unusually favorable growth conditions (reduced stability, increased transparency and, presumably, nutrient reserves) during the November survey relative to November 1955 and 1956 at 8°45'N, 79°23'W, the anticipated heightened phytoplankton response was not observed. 8. During the November survey, the local diatom responses and their regional fluctuations could be satisfactorily related to the accompanying surface salinity conditions. However, this correspondence is undoubtedly attributable to factors associated with the observed salinity levels, probably nutrients, rather than salinity directly. 9. Unusually warm conditions occurred during the March survey, attributable to considerably weaker upwelling winds than normally occurring then, which contributed to a considerably lower standing crop and a retardation in succession of three to five weeks relative to that observed during 1955-1957 at 8°45'N, 79°23'W in the Gulf of Panama. 10. During the March survey, a well defined inverse relationship existed between mean temperature and mean diatom abundance in the upper ten meters, and between transparency and mean diatom abundance. A direct relationship occurred between surface salinity and mean diatom abundance in the upper ten meters. These relationships are interpreted to indicate that diatom abundance primarily reflected the nutrient concentrations associated with a given upwelling intensity, rather than describing casual relationships. 11. The survey results indicate that the phytoplankton dynamics observed at 8°45'N, 79°23'W from November, 1954 through May, 1957 are generally representative of the Gulf of Panama. 12. The following new forms, to be described in a later publication, were observed during the surveys: Actinoptychus undulatus f. catenata n.f., Asterionella japonica f. tropicum n.f., Leptocylindrus maximus n. sp., Skeletonema costatum f. tropicum n.f. SPANISH: 1. La Comisión Interamericana del Atun Tropical recolectó en el Golfo de Panama muestras cuantitativas de fitoplancton en la superficie y a los diez metros, como sigue: a) Del 18 al 21 de marzo de 1958 (31 estaciones)-durante el maximum de la estación de afloramiento. b) Del 10 al 12 de julio de 1957 (10 estaciones)-durante la epóca de transición a la estación lluviosa cuando reaparecen los vientos ligeros que causan el afloramiento. c) Del 7 al 8 de noviembre de 1957 (15 estaciones)-durante el maximum de la estación lluviosa. 2. Las poblaciones maximas de fitoplancton aparecieron durante la estación de afloramiento, seguido por una considerable disminución durante el mes de julio y una calma durante noviembre. 3. Durante la investigación se observó una remarcable uniformidad regional en la composición de las especies a pesar de las diferencias regionales en las condiciones de crecimiento. Las diatomeas predominaban en gran numero en las comunidades. 4. Durante todas las investigaciones, las regiones mas cerca de la costa, generalmente al norte de los 8°30'N, eran las mas productivas. Las areas menos productivas fueron las mar afuera de las Bahias de San Miguel y Parita, lo que sugiere que el aumento en las sales nutritivas causado por las escorrentias es inadecuado para sostener poblaciones grandes de plantas autotróficas en estas regiones. 5. Durante todas las investigaciones, el crecimiento del fitoplancton parecio estar limitado por la disponibilidad de las. sales nutritivas. 6. Durante todas las investigaciones el crecimiento del fitoplancton parecio estar relacionado con la profundidad de la columna de agua. 7. Aunque las precipitacion por debajo del promedio normal contribuyo a condiciones desusadamente favorables de crecimiento (estabilidad reducida, aumento de la transparencia y, presumiblemente, de la reserva de sales nutritivas) durante la investigación de noviembre en relación a noviembre de 1955 y de 1956 en los 8°45'N, 79°23'W, no se observo-la alta reacción de fitoplancton que se esperaba. 8. Durante la investigación de noviembre, las reacciones locales de las diatomeas y sus fluctuaciones regionales pudieron relacionarse en forma satisfactoria con condiciones asociadas con la salinidad de la superficie. Sin embargo, esta correspondencia puede atribuirse sin duda a factores asociados con los niveles observados de salinidad, probablemente con las sales nutritivas, en lugar de directamente con la salinidad. 9. Condiciones calurosas no comunes ocurrieron durante la investigación de marzo, las que pueden atribuirse a que los vientos que ocasionan el afloramiento fueran mas debiles que los normales, lo que contribuyó a que la cosecha estable fuera considerablemente mas baja y a la demora de tres a cinco semanas en la sucecion relativa a la que se observó durante 1955-1957 en los 8°45'N, 8°23'W, en el Golfo de Panama. 10. Durante la investigación de marzo, existió una relación inversa bien definida entre la temperatura y la abundancia media de las diatomeas en los diez metros superiores, y entre la transparencia y la abundancia media de las diatomeas. Una relación directa ocurrio entre la salinidad de superficie y la abundancia media de las diatomeas en los diez metros superiores. Estas relaciones se interpretan como indicadoras de que la abundancia de diatomeas refleja primeramente las concentraciones de las sales nutritivas asociadas con una intensidad de afloramiento dada, en lugar de describir relaciones causales. 11. Los resultados de la investigacion indican que la dinamica del fitoplancton observada en los 8°45'N, 79°23'W, desde noviembre de 1954 a mayo de 1957, es generalmente representativa del Golfo de Panama. 12. Durante las investigaciones se observaron las siguientes formas nuevas, las que seran descritas en una publicación posterior: Actinoptychus undulatus f. catenata n.f., Asterionella japonica f. tropicum n.f., Leptocylindrus maximus n. sp., Skeletonema costatum f. tropicum n.f.

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During June 1974 the California Department of Fish and Game, in cooperation with the Sea Grant program at Moss Landing Marine Laboratories, conducted an exploratory fishing cruise that extended from La Jolla to Santa Cruz and included the Channel Islands, concentrating on inshore waters. The cruise was preliminary to the initiation of a major program of squid research and had six objectives: 1) To gather samples of market squid (Lo1igo opa1escens) for population, growth, aging and food chain studies. 2) To locate potential new fishing grounds. 3) To investigate methods for determining spawning intensity. 4) To gather data on oceanographic parameters of the spawning grounds. 5) To make incidental collections as requested by other investigators. 6) To familiarize Sea Grant personnel with the capabilities of the Department's largest research vessel, ALASKA, with respect to squid. Especially good weather and oceanographic conditions persisting throughout the cruise enabled us to make 66 night1ight stations, 17 midwater trawls and eight bottom trawls. Fishable concentrations of squid were discovered in the areas between Cape San Martin and Partington Point, between Pfeiffer Point and Point Sur, and in Carmel Bay, heretofore unfished. Squid spawning off Santa Cruz Island was observed utilizing an underwater observation chamber aboard the vessel. Mating and feeding behavior were observed in shipboard aquaria. PDF contains 28 pages)

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This report presents oceanographic data supporting the detailed chemical studies in the VERTEX Particle Interceptor Trap (PIT) experiment off the central California coast. Prior to the deployment of the PITs, an oceanographic survey of the intended study area was made on R/V CAYUSE from 17 to 21 August 1980. During this cruise, twenty CTD stations (Fig. 1) were occupied in a grid centered about the PIT site selected earlier based on archival oceanographic data. During the second leg of the VERTEX experiment from 25 August to 3 September, CTO profiles were taken as time permitted. In addition, a short survey near the PITs was made on 2 September. The intent of the pre-deployment cruise was to obtain data characterizing the vertical and horizontal variability of physical and chemical properties and to map the geostrophic flow field. Toward this end, vertical profiles of salinity, temperature and dissolved oxygen were made using a Plessey 9040 CTOa profiler. Considerable effort was expended to make vertical beam attenuation profiles to

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In this report, we present oceanographic results from VERTEX 3 Particle Interceptor Trap (PIT) experiment conducted off the western-coast of Mexico during October to November 1982. The oceanographic data presented here were obtained during three cruise legs by Moss Landing Marine Laboratory scientists aboard R/V Cayuse while the detailed chemical studies were done by other scientists aboard R/V Wecoma. Only the oceanographic data will be presented in this report. (PDF contains 82 pages)

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The estuarine populations of juvenile Atlantic and gulf menhaden (Brevoortia tyrannus and B. patronus) were sampled during two-boat, surface-trawl, abundance surveys extensively conducted in the 1970s. Juvenile Atlantic menhaden were sampled in 39 estuarine streams along the U.S. Atlantic coast from northern Florida into Massachusetts. Juvenile gulf menhaden were sampled in 29 estuarine streams along the Gulf of Mexico from southeast Texas into western Florida. A stratified, two-stage, cluster sampling design was used. Annual estimates of relative juvenile abundance for each species of menhaden were obtained from catch-effort data from the surveys. There were no significant correlations, for either species, between the relative juvenile abundance estimates and fishery-dependent estimates of year-class strength. From 1972 to 1975, the relative abundance of juvenile Atlantic menhaden in north Atlantic estuaries decreased to near zero. (PDF file contains 22 pages.)

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The utilization of waste waters in aquaculture were briefly reviewed. At the National Institute for Freshwater Fisheries Research (NIFFR), stocking density (20 to 160 fish/m super(3)) experiments using Sarotherodon galilaeus (without supplementary feeding) in floating cages were carried out in a sewage pond (0.4ha surface area). Cage culture of S. galilaeus was observed to have potentials in waste waters aquaculture. Recommendations were made on the execution of an intergrated waste water management and utilization.

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Monthly fish surveys were made from 1997-1999 in the Kenyan waters of Lake Victoria in order to estimate the magnitude of fisheries resources. Sample sites were defined using GPS while thirty minute hauls in alternate grid squares were made. Demersal fish biomass was estimated using the swept area method, while for trawling two different trawl nets were used. Collected fish was sorted into species, measured (TL) and weighed. Smaller fish were mixed on deck and sub-samples taken. Sexual maturity stages of fish were also observed. Areas with consistency high catches were located outside major urban and riverine influence where most artisanal fishermen were concentrated. Very low catches were obtained from areas that had recently been covered by water hyacinth Eichhornia crassipes

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A lakewide hydroacoustic research programme was designed in the Ugandan waters of Lake Victoria in order to ascertain the status of fish stocks. Data obtained from the hydroacoustic surveys were complemented with by catch data from multi mesh gillnets and frame trawls to validate acoustic estimates. Fish were distributed over the whole survey area, though the densities and species composition varied from place to place. Echo traces showed the fish formed schools during daytime and became more dispersed towards evening. Approximately equivalent indices of abundance were estimated for Rastrineobola argentea and Haplocromines. The distribution of the freshwater prawn, Caridina nilotica and the lakefly Chaoborus sp. was patchy. Dense swarms of Chaoborus larvae were observed to disperse from the lake bottom as the night approached thus assuring echo-traces formed by fish on the echogram and making their interpretation difficult. Caridina nilotica were observed to form dense echo-traces at the thermocline

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In studying sexual attraction in gammarids of the group pulex, it has seemed necessary to dissociate the processes of moulting and ovogenesis in order to recognize their respective effects on this phenomenon. For this purpose a synthetic hormone, ecdysterone, was utilized. In the first instance the author followed the action of the hormone on isolated females in vitellogenesis. It was proved that the behaviour of Gammarus pulex and Gammarus fossarum vis-a-vis the ecdysterone used proves to be very close to that of isopods that was observed in Orchestia gammarellus in earlier research. Although they were in vitellogenesis, the females saw their intermoult cycle shortened.

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As it is clearly stated in the title, this book section aims to identify fishers' livelihoods and their role as a stakeholder in the process of co-management with the other stakeholders and official institutions within the LVFRP.