A study of the age, growth, sexual maturity, and spawning of the anchoveta, Cetengraulis mysticetus, in the Gulf of Panama

ENGLISH: Crew members of tuna clippers and Commission personnel are collecting specimens of anchovetas (Cetengraulis mysticetus) for studies of the biology of this important tuna-bait species. More than 27,000 fish from 231 collections captured in the Gulf of Panama between June 1951 and January 1956 are the basis of this study of the age, growth, sexual maturity, and spawning season of this species in that area. Estimates of age and rate of growth were made by studying the temporal progression of modal size groups from monthly length frequency distributions. Sexual development and time of spawning were determined from gross examination of ovaries and measurements of ovarian eggs. SPANISH: Con el fin de estudiar la biología de la anchoveta (Cetengraulis mysticetus) los tripulantes de los barcos atuneros y el personal de la Comisión están recolectando especimenes de esta importante especie de carnada para capturar el atún. Mas de 27,000 ejemplares de las 231 colecciones hechas en el Golfo de Panamá entre junio de 1951 y enero de 1956, sirven de material al presente estudio sobre la edad, el crecimiento, la madurez sexual y las épocas de desove de esta especie en el área indicada. Las estimaciones de la edad y de la proporción del crecimiento fueron hechas a base del estudio de la progresión temporal de los grupos modales de tamaño en las distribuciones mensuales de frecuencias de longitud. El desarrollo sexual y el periodo de desove fueron determinados mediante el examen microscópico de los ovarios y las mediciones de los huevos ováricos. (PDF contains 79 pages.)

Markets, marketing and production issues for aquaculture in East Africa: the case of Uganda

Aquaculture is currently responsible for an insignificant proportion of total fish production in Uganda. However, given the increasing demand for fresh fish in urban and peri-urban araes, and threats to the supply of fish from natural catch fisheries, the potential exists for a strong market in aquaculture. Small-scale fish farmers located relatively close to markets or all-season roads, and who can supply consistent and high quality produce, will have the widest range of marketing opportunities, and will likely be within the area of operation of potential traders and intermediaries that deliver fish to markets. Fish farmers that are not close to roads, or produce unreliable quantities and variable quality products may face high transaction costs of marketing their product, and decreasing net returns to production. The authors found that significant on-farm labor, and access to input markets are important factors leading to positive net returns to fish production. Areas with high population density and relatively low wages will be well suited to labor intensive aquaculture. The authors concluded that aquaculture development has good potential in certain areas of Uganda and should therefore be pursued as a potential development pathway. However, policy makers should consider the importance of the price of fresh fish relative to the cost of labor, as well as other factors including the importance of smallholder credit and access to extension services, when directing investments in aquaculture technology.

The effect of Rosmarinus officinalis and Zataria multiflora extracts on the stability of poly unsaturated fatty acids in frozen silver carp minced

The purpose of this study, Evaluation the effect of Rosmarinus officinalis and Thymus vulgaris extracts on the stability of poly unsaturated fatty acids in frozen Silver carp minced. Treatments include: Treatment 1 - Control: frozen meat packaged in conventional Treatment 2: Frozen Silver carp minced+Thyme 300 mg/kg in normal packaging Treatment 3: Frozen Silver carp minced+Rosemary 200 mg/kg in normal packaging Treatment 4: Frozen Silver carp minced+Rosemary compound (100 mg/kg) and Thyme (100 mg/kg) in normal packaging After rapid freezing of samples in the spiral freezer by individual quick freezing method, to maintain the cold temperature (-18) °C were transferred. Sampling and measurements to determine the fatty acid profile of the zero phase beginning in the first month and then every ten days, and 15 days in the second month of the third month after the monthly test. Identifying, defining and measuring the fatty acid profile by gas chromatography was performed. In this study, levels of both saturated and unsaturated fatty acids in three experimental and one control were identified as follows: A: saturated fatty acids: Meristic C14: 0/Palmitic C16: 0/Hepta decaenoic C17: 0/Stearic C18: 0/Arashidic C20: 0/B:Mono unsaturated fatty acids: palmitoleic C16: 1-W7/Oleic C18: 1-W9/Gadoleic C20: 1-W9 C:Poly unsaturated fatty acids: Linoleic C18: 2-W6/α-Linolenic C18: 3-W3 D:High unsaturated fatty acids: Arachidonic C20: 4-W6 Eicosapentaenoic acid C20: 5-EPA/W3 Docosahexaenoic C22: 6-DHA/W3 Results of this study was to determine, Thyme and rosemary extracts containing silver carp minced stored in freezing conditions, Stability of different types of fatty acids, monounsaturated fatty acids, poly-unsaturated fatty acids, omega-3 and omega-6 fatty acids are. So that none of the fatty acids measured were not significant 100% increase or decrease, While changes in the fatty acid oxidation during storage time is minimized. The results obtained from the fatty acid profiles and indicators of their and statistical tests show that treatment with rosemary extract More stable during storage (-18) ° C In comparison with the control and other treatments are shown; And at relatively low compared to other treatments and control samples oleic acid and linoleic acid, palmitic more. According to studies,in Silver carp minced that containing rosemary extract, end of the storage period of six months. Were usable, so even rosemary extract the shelf-life examples to increase more than six months.

Study of the development and evolution of seasonal thermocline and turbulent processes in the northern parts of Persian Gulf using numerical modeling

The Persian Gulf (PG) is a semi-enclosed shallow sea which is connected to open ocean through the Strait of Hormuz. Thermocline as a suddenly decrease of temperature in subsurface layer in water column leading to stratification happens in the PG seasonally. The forcing comprise tide, river inflow, solar radiation, evaporation, northwesterly wind and water exchange with the Oman Sea that influence on this process. In this research, analysis of the field data and a numerical (Princeton Ocean Model, POM) study on the summer thermocline development in the PG are presented. The Mt. Mitchell cruise 1992 salinity and temperature observations show that the thermocline is effectively removed due to strong wind mixing and lower solar radiation in winter but is gradually formed and developed during spring and summer; in fact as a result of an increase in vertical convection through the water in winter, vertical gradient of temperature is decreased and thermocline is effectively removed. Thermocline development that evolves from east to west is studied using numerical simulation and some existing observations. Results show that as the northwesterly wind in winter, at summer transition period, weakens the fresher inflow from Oman Sea, solar radiation increases in this time interval; such these factors have been caused the thermocline to be formed and developed from winter to summer even over the northwestern part of the PG. The model results show that for the more realistic monthly averaged wind experiments the thermocline develops as is indicated by summer observations. The formation of thermocline also seems to decrease the dissolved oxygen in water column due to lack of mixing as a result of induced stratification. Over most of PG the temperature difference between surface and subsurface increases exponentially from March until May. Similar variations for salinity differences are also predicted, although with smaller values than observed. Indeed thermocline development happens more rapidly in the Persian Gulf from spring to summer. Vertical difference of temperature increases to 9 centigrade degrees in some parts of the case study zone from surface to bottom in summer. Correlation coefficients of temperature and salinity between the model results and measurements have been obtained 0.85 and 0.8 respectively. The rate of thermcline development was found to be between 0.1 to 0.2 meter per day in the Persian Gulf during the 6 months from winter to early summer. Also it is resulted from the used model that turbulence kinetic energy increases in the northwestern part of the PG from winter to early summer that could be due to increase in internal waves activities and stability intensified through water column during this time.

Review of river fisheries valuation in tropical Asia

This study attempts to estimate the economic value of riverine fisheries in tropical Asia and quantify the economic impacts of any changes to the environment that affects rivers and hence fisheries. The value of riverine fisheries has been considered in the following two ways: firstly, through a compilation and summary of the results of existing studies on this topic; secondly, by estimating the direct use value of riverine and floodplain fishing by country using quantities and freshwater fish prices derived from various sources. Furthermore, a review of the characteristics of the fisheries is presented. These fisheries have been shown to be valuable (i.e., economically or socially important) in at least two specific ways: as a generator of commercially marketable output, and as a source of income and employment in relatively impoverished communities.

Benthic sampling program in Biscayne Bay, 1981-1982

The Biscayne Bay Benthic Sampling Program was divided into two phases. In Phase I, sixty sampling stations were established in Biscayne Bay (including Dumfoundling Bay and Card Sound) representing diverse habitats. The stations were visited in the wet season (late fall of 1981) and in the dry season (midwinter of 1982). At each station certain abiotic conditions were measured or estimated. These included depth, sources of freshwater inflow and pollution, bottom characteristics, current direction and speed, surface and bottom temperature, salinity and dissolved oxygen, and water clarity was estimated with a secchi disk. Seagrass blades and macroalgae were counted in a 0.1-m2 grid placed so as to best represent the bottom community within a 50-foot radius. Underwater 35-mm photographs were made of the bottom using flash apparatus. Benthic samples were collected using a petite Ponar dredge. These samples were washed through a 5-mm mesh screen, fixed in formalin in the field, and later sorted and identified by experts to a pre-agreed taxonomic level. During the wet season sampling period, a nonquantitative one-meter wide trawl was made of the epibenthic community. These samples were also washed, fixed, sorted and identified. During the dry season sampling period, sediment cores were collected at each station not located on bare rock. These cores were analyzed for sediment size and organic composition by personnel of the University of Miami. Data resulting from the sampling were entered into a computer. These data were subjected to cluster analyses, Shannon-Weaver diversity analysis, multiple regression analysis of variance and covariance, and factor analysis. In Phase II of the program, fifteen stations were selected from among the sixty of Phase I. These stations were sampled quarterly. At each quarter, five Petite Ponar dredge samples were collected from each station. As in Phase I, observations and measurements, including seagrass blade counts, were made at each station. In Phase II, polychaete specimens collected were given to a separate contractor for analysis to the species level. These analyses included mean, standard deviation, coefficient of dispersion, percent of total, and numeric rank for each organism in each station as well as number of species, Shannon-Weaver taxa diversity, and dominance (the compliment of Simpson's Index) for each station. Multiple regression analysis of variance and covariance, and factor analysis were applied to the data to determine effect of abiotic factors measured at each station. (PDF contains 96 pages)

Diel differences in catches of Western Baltic Spring Spawning Herring Larvae (Clupea harengus)

Comparative night and day catches of herring larvae were taken during the Rügen-Herring-Larval-Survey (RHLS) in 2007 and 2008 in the Greifswalder Bodden which is the main spawning area of the Western Baltic Spring Spawning Herring. The quantities and the size composition of larvae caught during night and day were examined. During night more larvae were caught compared to the samples taken at daytime, especially with larvae larger than 25 mm. This indicates avoidance reactions, which increase with the developmental stage of the larvae. The differences of the night and day catches are relatively constant until a length of about 25 mm, thus the night/day effect does not influence estimations concerning larvae smaller than 25 mm (e.g. N20 index). There might be an impact on estimations for larger larvae due to the night/day effect. For further research other aspects like cloud coverage at night, phase of the moon, underwater visibility and turbidity should be taken into account. These aspects might influence the avoidance reactions.

Aktivitäten des nationalen Fischereidatenerhebungsprogramms im Jahr 2004

Based on the EU Regulation 1543/2000 for the improvement of quantity and quality of fishery data the Federal Ministry for Consumer Protection, Food and Agriculture has initiated a national data collection programme, executed by three institutions, Federal Research Centre for Fisheries (BFAFi), Federal Agency for Ariculture and Food and the Federal Research Centre Agriculture, co-ordinated by BFAFi. In 2004 samples have been taken from 943 hauls during 29 commercial fishing trips; 357 000 fish have been measured. From 2002 to 2004 the number of length and weight and measurements, and age determinations could increased by 32, 65 and 156 % resp. Pilot inquiries have been carried out to prepare also the collection of economical date of fishing vessels and of fish processing plants from 2006.

Gegenüberstellung von mathematisch-physikalischer Modellierung und Messungen an geschleppten fischereitechnischen Systemen

When drafting a new model of a towed technical system for fisheries (trawl, towed TV gear or similar), and also when measuring an existing and already tested system it is not easy to foresee of practical behaviour, which depends of various parameters. The measuring programme for recording all data needs a lot of time and money, and also has some limitations. Therefore we developed for such systems mathematical-physical models, which allow a complex calculation. Their real value, however, results only from practical verification. During the cruise no. 222 of “Walther Herwig III” in November 2000 comparative investigations for 2concrete systems were carried out. This was done in cooperation with the University in Rostock, where such models are being developed and computerized. One of the systems mesasured was a pelagic herring trawl and the other one the towed TV gear for underwater observations of the Institute for Fishery Technology and Fish Quality. The correspondence between model calculation and measurements was very high for both systems.

Fishermen cooperatives in the Green Revolution Programme

The aim of this study was to examine areas in which fishermen cooperatives can become involved and then suggest operational guidelines in order to increase fishermen income and also to make the Green Revolution Programme a success through increased production of fish. The paper enumerated different areas in which fishermen cooperatives can participate. These include: thrift and credits, thrift and savings, consumers and building cooperative societies. It is the belief of the author that the expansion of fishermen cooperatives into the areas mentioned in this paper can enable members to process and market their products more economically, buy supplies and equipment in large quantities and obtain lower cost credit

Makrelen- und Holzmakrelenfänge stimmen zuversichtlich

In order to determine the abundance of incoming year classes of both mackerel and horse mackerel a couple of research vessels in the frame of ICES investigats waters west of the British Isles, the Gulf of Biscay and areas west of the Iberian Peninsula in the first half of each third year. In 1995, Germany took place in these investigations with R.V. "Walther Herwig III" from March 23 to April 18. A total of 100 plankton stations were made using a Gulf - III - Sampier between Fastnet Rock and the Gironde estuary. In addition, 87 fishing stations were occupied by a GOV net. Though fish indications were not fished on purpose large amounts of especially horse mackerel and mackerel were gained in the half hour tows. Besides, boarfish (Capros aper L.), blue whiting, and sprat were found in considerable quantities and numbers in some areas. The hydrographc situation was as expected: The development of a surfaee thermocline created by radiation indieates the collapse of the vertically homogeneous situation of the winter period.

A Positive trajectory for corals at Little Cayman Island

Coral reefs are damaged by natural disturbances and local and global anthropogenic stresses. As stresses intensify, so do debates about whether reefs will recover after significant damage. True headway in this debate requires documented temporal trajectories for coral assemblages subjected to various combinations of stresses; therefore, we report relevant changes in coral assemblages at Little Cayman Island. Between 1999 and 2012, spatiotemporal patterns in cover, densities of juveniles and size structure of assemblages were documented inside and outside marine protected areas using transects, quadrats and measurements of maximum diameters. Over five years, bleaching and disease caused live cover to decrease from 26% to 14%, with full recovery seven years later. Juvenile densities varied, reaching a maximum in 2010. Both patterns were consistent within and outside protected areas. In addition, dominant coral species persisted within and outside protected areas although their size frequency distributions varied temporally and spatially. The health of the coral assemblage and the similarity of responses across levels of protection suggested that negligible anthropogenic disturbance at the local scale was a key factor underlying the observed resilience.

Control charts: an application in shrimp canning

Control chart is a statistical tool which can be employed with advantage to learn the situation in the process (whether it is under control or not). There are different kinds of control charts but one which is most commonly used is the control chart for variables, known as X-R chart. This chart can be used for measurable characteristics in food industry like appearance, colour, sizes and dimensions for chemical properties such as moisture, fat and many other analytical counts and measurements. Since construction and maintenance of such charts involve a recognizable amount of time and effort, they should not be used indiscriminately but only where it can be definitely shown that their use improves the overall operation. Since one control chart can be used for only one quality attribute, those for which the charts are used should be selected with care (Kramer and Twigg, 1962). In this article, the procedure of setting up a variable control chart is described with observations taken on filling operation of cans in a shrimp canning factory.

Annual Report of the Game Department for the year ended 31st December 1938

The annual report presents information on the following under fisheries section Breaches of Game Laws (Fish Sections) Development and Control of the Lake Victoria Fishing Industry. Collection of Statistics Statistical Tables.- (A) Number of half-yearly licences issued (B) Quantities and value of nets imported (C) Dried fish handled by Railways and Steamers (D) Smoked and salted fish exported to the Belgian Congo Mpondwe Customs Post Lake Bunyonyi Lake Mugisha (or Kaiyumbu) Lake Chahafi Lake Mulehe Lake Mutanda Lake Saka Lake Nabugabo Lake Kachira and Lake Kijanebalola Lake Kyoga Commercial Development:- Lake Edward and associated fisheries Uganda Fisheries Limited Nsonzi Fishery, Kigezi Experimental Nets in Lake Victoria Legislation (B) angling a) Trout (b) Nile pereh or mpufa

Assessing Biological Control Damage of Giant Salvinia with Field Reflectance Measurements and Aerial Photography

A study was conducted on a small pond in southeast Texas to evaluate the potential for using remote sensing technology to assess feeding damage on giant salvinia ( Salvinia molesta Mitchell) by the salvinia weevil ( Cyrtobagous salviniae Calder and Sands). Field spectral measurements showed that moderately damaged and severely damaged plants had lower visible and near-infrared reflectance values than healthy plants. Healthy, moderately damaged, and severely damaged giant salvinia plants could be differentiated in an aerial color-infrared photograph of the study site. Computer analysis of the photograph showed that the three damage level classes could be quantified. (PDF has 5 pages.)