On the computation of space-time correlations by large-eddy simulation

The effect of subgrid-scale (SGS) modeling on velocity (space-) time correlations is investigated in decaying isotropic turbulence. The performance of several SGS models is evaluated, which shows superiority of the dynamic Smagorinsky model used in conjunction with the multiscale large-eddy simulation (LES) procedure. Compared to the results of direct numerical simulation, LES is shown to underpredict the (un-normalized) correlation magnitude and slightly overpredict the decorrelation time scales. This can lead to inaccurate solutions in applications such as aeroacoustics. The underprediction of correlation functions is particularly severe for higher wavenumber modes which are swept by the most energetic modes. The classic sweeping hypothesis for stationary turbulence is generalized for decaying turbulence and used to analyze the observed discrepancies. Based on this analysis, the time correlations are determined by the wavenumber energy spectra and the sweeping velocity, which is the square root of the total energy. Hence, an accurate prediction of the instantaneous energy spectra is most critical to the accurate computation of time correlations. (C) 2004 American Institute of Physics.

Spawn production of common carp

(4 p.)

Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish

Foreword [pdf, < 0.1 MB] Acknowledgements PHASE 1 [pdf, 0.2 MB] Summary of the PICES/NPRB Workshop on Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish (July 19–20, 2007, Seattle, U.S.A.) Background Links to Other Programs Workshop Format Session I. Status of climate change scenarios in the PICES region Session II. What are the expected impacts of climate change on regional oceanography and what are some scenarios for these drivers for the next 10 years? Session III. Recruitment forecasting Session IV. What models are out there? How is climate linked to the model? Session V. Assumptions regarding future fishing scenarios and enhancement activities Session VI Where do we go from here? References Appendix 1.1 List of Participants PHASE 2 [pdf, 0.7 MB] Summary of the PICES/NPRB Workshop on Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish (October 30, 2007, Victoria, Canada) Background Workshop Agenda Forecast Feasibility Format of Information Modeling Approaches Coupled bio-physical models Stock assessment projection models Comparative approaches Similarities in Data Requests Opportunities for Coordination with Other PICES Groups and International Efforts BACKGROUND REPORTS PREPARED FOR THE PHASE 2 WORKSHOP Northern California Current (U.S.) groundfish production by Melissa Haltuch Changes in sablefish (Anoplopoma fimbria) recruitment in relation to oceanographic conditions by Michael J. Schirripa Northern California Current (British Columbia) Pacific cod (Gadus macrocephalus) production by Caihong Fu and Richard Beamish Northern California Current (British Columbia) sablefish (Anoplopoma fimbria) production by Richard Beamish Northern California Current (British Columbia) pink (Oncorhynchus gorbuscha) and chum (O. keta) salmon production by Richard Beamish Northern California Current (British Columbia) ocean shrimp (Pandalus jordani) production by Caihong Fu Alaska salmon production by Anne Hollowed U.S. walleye pollock (Theragra chalcogramma) production in the eastern Bering Sea and Gulf of Alaska by Kevin Bailey and Anne Hollowed U.S. groundfish production in the eastern Bering Sea by Tom Wilderbuer U.S. crab production in the eastern Bering Sea by Gordon H. Kruse Forecasting Japanese commercially exploited species by Shin-ichi Ito, Kazuaki Tadokoro and Yasuhiro Yamanka Russian fish production in the Japan/East Sea by Yury Zuenko, Vladimir Nuzhdin and Natalia Dolganova Chum salmon (Oncorhynchus keta) production in Korea by Sukyung Kang, Suam Kim and Hyunju Seo Jack mackerel (Trachurus japonicus) production in Korea by Jae Bong Lee and Chang-Ik Zhang Chub mackerel (Scomber japonicus) production in Korea by Jae Bong Lee, Sukyung Kang, Suam Kim, Chang-Ik Zhang and Jin Yeong Kim References Appendix 2.1 List of Participants PHASE 3 [pdf, < 0.1 MB] Summary of the PICES Workshop on Linking Global Climate Model Output to (a) Trends in Commercial Species Productivity and (b) Changes in Broader Biological Communities in the World’s Oceans (May 18, 2008, Gijón, Spain) Appendix 3.1 List of Participants Appendix 3.2 Workshop Agenda (Document contains 101 pages)

Guide to the meso-scale production of the copepod Acartia tonsa

This manual is intended as a guide for the daily production of a few million A. tonsa nauplii for feeding to marine vertebrates and invertebrates. This scale of production is greater than most research would require, but smaller than commercial production, hence the term meso-scale production. This manual will briefly describe the biology of Acartia tonsa Dana that is relevant to culture, the culture methodology for meso-scale production of their eggs and nauplii, the system components utilized in production, and how to construct a few simple tools useful for this scale of production. Commercial production of copepods requires much greater feed production than is described, or the development of an efficient artificial feed, and, therefore, is not the focus of this manual. (PDF conatains 29 pages.)

Reproduction, maturation, and seed production of cultured species: Proceedings of the Twelfth U.S.-Japan Meeting on Aquaculture, Baton Rouge, Louisiana, October 25-29, 1983

The United States and Japanese counterpart panels on aquaculture were formed in 1969 under the United States-Japan Cooperative Program in Natural Resources (UJNR). The panels currently include specialists drawn from the federal departments most concerned with aquaculture. Charged with exploring and developing bilateral cooperation, the panels have focused their efforts on exchanging information related to aquaculture which could be of benefit to both countries. The UJNR was begun during the Third Cabinet-Level Meeting of the Joint United States-Japan Committee on Trade and Economic Affairs in January 1964. In addition to aquaculture, current subjects in the program include desalination of seawater, toxic microorganisms, air pollution, energy, forage crops, national park management, mycoplasmosis, wind and seismic effects, protein resources, forestry, and several joint panels and committees in marine resources research, development, and utilization. Accomplishments include: Increased communication and cooperation among technical specialists; exchanges of information, data, and research findings; annual meetings of the panels, a policy-coordinative body; administrative staff meetings; exchanges of equipment, materials, and samples; several major technical conferences; and beneficial effects on international relations. (PDF file contains 79 pages.)

Small scale commercial production of tilapia fingerlings in floating bamboo net-hapas

The inadequate supply of tilapia seed is considered as one of the major present constraints to the development of the culture industry in Nigeria. The floating bamboo net-hapa hatchery/nursery system was observed to be very efficient in the mass production of tilapia (Oreochromis niloticus) fry and fingerlings at Kainji Lake Research Institute. This system was therefore, recommended for small-scale (artisanal) commercial operators consisting of fishermen families in order to increase their productivity and hasten development of rural communities. The economic analysis of this system showed that loan obtained for the recommended scale of operation can be amortized within 2 years of the project. It was emphasized that the operational and managerial skills of the fish farm operators account largely to the production cost and profitability of the enterprise

Small-scale commercial production of tilapia fry and fingerlings in concrete raceways

This paper discusses the investment prospects in Tilapia fry and fingerling production in raceways created from the concrete drainage channel of a reservoir or pond of an existing fish farm in Nigeria. With an initial capital of 1,300 and an annual operating cost of 310 spent on procurement of fish feed and brood stock for a 10 m super(2) raceway per se, a net profit of 4,100 and 5,090 would be realized from Sarotherodon galilaeus in the first year and subsequent years of production respectively, assuming that the fingerling production rate has been maintained through the production period. It is concluded that the application of this approach of optimizing the use of available resources in the fish farm for the productive breeding of Tilapia fry and fingerlings will apart from alleviating the problem of scarcity of stocking materials in the country, increase the profit margin accruing to the fish farmer

Commercial production of Clarias fry and fingerlings in indoor and outdoor concrete tank systems

Induced breeding technique by hypophysation is being applied at the Kainji Lake Research Institute Fisheries Division Hatchery complex in New Bussa, Nigeria, for the production of Clarias fry and fingerlings in indoor and outdoor concrete tank systems. The hatchlings are fed on livefood (zooplankton) and artificial feed. Source of zooplankton is from cultured stock which is maintained throughout the breeding season by fertilization. Production values show that an average of over 4,000 hatchlings (larvae) can be produced by a female breeder (over-700g wt) and percentage survival after two months ranges between 70 to 75%. With the proposed modification and expansion project, an estimated production of over 0.5 million fingerlings per breeding season is projected

Investment prospects in the production of the common carp (Cyprinus carpio) fingerlings in freshwater ponds

Since the introduction of Common carp Cyprinus carpio in Oyo State (Nigeria) from Israel in 1964, various local breeding methods have been employed in carp rearing to improve the survival rate at all stages of development during breeding. The physico-chemical parameters of the ponds which were simultaneously investigated for carp rearing in this study includes temperature (t), dissolved oxygen (DO) and hydrogen-ion concentration (pH). However, high rates of water displacement in the breeding ponds were unfavourable to the development of zooplankton which play important role in the food web of C. carpio. The survival rates of 15.88-69.50% and 19.60-33.83% obtained for the egg-hatchling and hatchling-fingerling stages respectively were encouraging. A breeding performance of this magnitude was found to be viable, breaking even in the fourth year. However, an increase in size of this trial project would be more profitable and increase fingerling supply as well as provide employment opportunities. This study thereby provides some baseline information on some local techniques and progress in the propagation of C. carpio and scope for further improvement

The potentials for commercial production of fish feeds in Nigeria

Studies in fish feed technology revealed that there is a potential for big time investment into fish feed production and marketing in view of the growing awareness of fish farming in Nigeria. Intensification of aquaculture is one of the primary methods of food (finfish) production which requires technical knowledge and expertise in the formulation and manufacture of adequate feeds for the cultured species. Studies also revealed that all sort of food items were used by fish farmers ranging from animal dung, groundnut cake etc, to culture fish to table size because of non-availability of rightly prepared feeds. Inadequate knowledge of detailed requirements of tropical cultured species was found to pose a hindrance to formulation despite the fact that a lot has been accumulated in terms of biochemical and nutritive values of food sources in Nigeria. The investigation further revealed the challenges posed to researchers in aquaculture, fish nutritionists and fisheries biologists among others to elucidate the complete requirements of local fish species in terms of their protein, lipid and carbohydrate requirements such that their patents could be made available to companies like PFIZER, IBRU etc, and individuals alike to make commercialization of fish feeds a reality