Technological aspects of preservation and processing of edible shell fishes III. Factors influencing the keeping quality of crab (Scylla serrata) during freezing and frozen storage

The possible factors leading to the loss of flavour and general quality of crab during freezing and frozen storage have been studied. The preprocess ice storage condition of the raw material was found to be one such important factor while the fresh frozen crab meat remained in good organoleptic condition for about 51 weeks at -23°C, the 7 days iced material held frozen was found to have a shelf life of about 21 weeks. The fall in myofibrillar protein noted during frozen storage together with the loss of myosin ATPase activity correlated well with the loss of organoleptic qualities.

An assessment of handling and processing methods used for the shrimp fishery by-catch in Kalpitiya, Sri Lanka

The by-catch from the shrimp trawl fishery in Kalpitiya is mainly used for the production of dried fish, which provides an additional source of income for fishermen in the area. It has been observed that current handling practices along the value addition chain are responsible for the poor quality and low price of the end product. This study was aimed at identifying the shortcomings in such handling practices by fishermen and dried fish producers and assessing the quality of shrimp fishery by-catch along the processing chain in order to recommend more efficient utilization methods that will improve the quality of the end product. Fresh fish, dried fish and harbour water samples were tested for total coli forms, faecal coliforms, E. coli and Salmonella in order to assess their microbial quality: In addition, standard plate counts (SPC) of fish samples were also carried out. A survey was carried out from July-October 2006 at Kalpitiya, using a pre-tested questionnaire to collect information from individuals who have been engaged in dried fish processing. Average values obtained for freshly landed and dried fish respectively, were, SPC 9.88x10 super(5) CFU/g and 30.43x10 super(5) CFU/g, total coliforms 23.05 and 24.23 MPN/g and fecal coliforms 8.28 and 9.00 MPN/g. These values exceed the recommendations in the SL standards. A quarter of the landed fresh fish and 38% of dried fish from the producers were positive for E. coli and thus failed to show required end product quality. SPC of harbour water was 14.35x10 super(6) CFU/ml and all samples were found to be contaminated with E. coli. None of the fishermen and dried fish producers were satisfied with the quality of the end product. The reasons for poor quality as indicated by them were: limited availability of ice (75%), lack of infrastructure facilities (65%), uncertainty of markets (52%), lack of emphasis on quality (47%) and poor access to available technologies (41%). Respondents to the questionnaire also identified: unavailability of potable water, insulated boxes, good landing jetty, racks for drying fish, poor cold storage facilities and limitations in dried fish storage facilities, as further factors leading to the loss of quality in their products. Results demonstrate that improvements to the infrastructure facilities and conducting of proper awareness programmes on handling practices could lead for improvements in the quality of value added products prepared from the shrimp fishery by-catch at Kalpitiya.

The Nile perch fishery: traditional and emerging fisheries, overfishing and the use of illegal gears on Lake Albert

The fisheries of Lake Albert have come under increasing focus due to several driving forces that have synergistically evolved resulting into concerns from diverse stakeholders. The driving forces include: the commercialization of the fisheries with entry into the value chain of industrial fish processing, a decline in fish stocks especially of the large-size fishes and the emergency of the light - fishing targeting small pelagic fishes. In addition, the assumption by some opinion leaders that light-fishing (use of light) has destroyed the Nile perch fishery of Lake Albert, other factors such as cross-border fishing conflicts, the emergence of oil, an influx of traders in fish-related activities, and the limited regulatory and enforcement regimes for the diverse commercially exploited fish fauna of Lake Albert all require continuous information and action.

The present status of the fishery for tilapia in Lake Victoria (Uganda)

The commercial fisheries of Lake Victoria are presently dominated by three species: the stocked Lates niloticus and Oreochromis niloticus, and the endemic cyprinid Rastrineobola argentea. The three comprise at least 90% of the commercial catch while the rest of the endemic species mostly occur as by-catch (incidental catch) except in localised areas. Apart from being a major source of food, the three species especially the Nile perch represent the usually recognized main forms of predation, As they exert a "top-down" effect on production, they are important in the trophic dynamics of the Lake Victoria ecosystem. However, another form of predation which is usually unrecognized in the lake productivity mechanisms is one due to fishing mortality. Fishermen essentially behave as predatory elements in the ecosystem. This is manifested in ways that paral1el the effect of fish as predators e.g. some fishermen are habitat restricted and specialised in catching particular species or sizes, others are opportunistic and switch to whatever species (prey) are available which may depend on season, etc. There are also indirect factors that influence fishing mortality as a form of predation e.g. availability on the market of different gears, thefts of nets and of fish from nets, civil strife, market demand etc. The fatter are essentially socioeconomic factors. Application of the principles of fisheries management requires "a data base from which effective options can be generated. It is considered that one of the fundamental requirements for such a data base is information on the spatial distribution of the species fishery. This can be combined with information on landings which can eventually be incorporated into a programme of stock monitoring. The aim of this paper is to highlight information on the Tilapia fishery that may benefit fisheries management.

Productivity factors and fish production and their fisheries management concerns

The fundamental purpose of fisheries management is to ensure sustainable production over time from fish stocks, preferably through regulatory and enhancement actions that promote economic and social well being of the fishers and industries that depend on the resource. To achieve this purpose, management authorities must design, justify and administer (enforce) a collection of restraints on fishing and fishery-related activities. Productivity and management of the fisheries should be based on the understanding that they are complex and dynamic systems. Physical, chemical and biological components support a community of organisms that is unique to the these systems. All these components are in constant change but mainly dictated by human interference in the water body ecosystem.

Aspects of the fishery and biology of the African catfish Clarias gariepinus (Burchell, 1822) amidst environmental changes in Lake Wamala (Uganda)

Environmental changes are some of the factors that affect fisheries and biological characteristics of fishes. The African catfish Clarias gariepinus (Burchell, 1822) has biological characteristics that enable it to persist under various stressful environmental conditions. However, few studies have examined how the African catfish responds to conditions created by a changing climate. The study examined some of the fishery and biological characteristics of African catfish in Lake Wamala (Uganda) to provide an understanding of their response to changing climatic conditions using data for the period 1950 - 2013. Temperature around the lake increased by 0.02ºC/year since 1980, commensurate with the regional trend, while rainfall was above average since 1996, except in 2004 and 2008. Lake depth was strongly positively correlated with rainfall (r =0.83, n= 6, p<0.05) up to 2000, after which, lake depth decreased amidst increase in rainfall. The contribution of African catfish increased from 20% to 85% and 17% to 78% respectively to commercial and experimental catches respectively between 1975 and 2013 despite the decrease in lake depth. The modal total length, condition factor, food, and fecundity did not change. Only size at first maturity decreased from 37.5 to 30 cm TL in females and 39.5 to 34.2 cm TL in males between 1999/2000 and 2012/2013. The biological characteristics of the African catfish were comparable with those of the same species in other lakes and remained relatively stable. The results suggested that the African catfish has the capacity to persist and/or adjust appropriately under conditions created by climate variability and change, and if properly managed, can sustain the fisheries of Lake Wamala.

PICES Press, Vol. 14, No. 1, January 2006

The state of PICES science - 2005 (pdf, 0.2 Mb) 2005 Wooster Award (pdf, 0.4 Mb) Korea and U.S. federate metadata collection (pdf, 0.3 Mb) PICES Interns (pdf, 0.3 Mb) Studies on long-term variation of ocean ecosystem / climate interactions based on the Odate collection (pdf, 0.2 Mb) Hokkaido University Fisheries & Oceanographic Database CD-ROM (pdf, 0.2 Mb) Workshop on sardine and anchovy fluctuations (pdf, 0.1 Mb) Photo highlights of PICES XIV (pdf, 0.4 Mb) Workshop on SEEDS-II (pdf, 0.2 Mb) NPAFC-PICES joint symposium "The status of Pacific salmon and their role in North Pacific marine ecosystems" (pdf, 0.2 Mb) PICES Calendar (pdf, 0.2 Mb) New Chairman of the PICES Fishery Science Committee (pdf, 0.1 Mb) The state of the western North Pacific in the first half of 2005 (pdf, 0.4 Mb) Latest and upcoming PICES publications (pdf, 0.4 Mb) Recent trends in waters of the subarctic NE Pacific (pdf, 0.2 Mb) The Bering Sea: Current status and recent events (pdf, 0.1 Mb) PICES and GLOBEC to sponsor workshop on sub-arctic seas (pdf, 0.1 Mb) Professor Mikhail N. Koshlyakov - 75 (pdf, 0.1 Mb) Obituary - Dr. Al Tyler (pdf, 0.1 Mb)

Annual report 2005 - North Pacific Marine Science Organization (PICES). Fourteenth meeting, Vladivostok, Russia, September 29-October 9, 2005

Report of Opening Session (pdf 0.07 Mb) Report of Governing Council (pdf 0.2 Mb) Report of the Finance and Administration Committee (pdf 0.07 Mb) Reports of Science Board and Committees Science Board inter-sessional meeting (pdf 0.07 Mb) Science Board (pdf 0.1 Mb) Biological Oceanography Committee (pdf 0.2 Mb) Fishery Science Committee (pdf 0.04 Mb) Marine Environmental Quality Committee (pdf 0.06 Mb) MONITOR Technical Committee (pdf 0.05 Mb) Physical Oceanography and Climate Committee (pdf 0.06 Mb) Technical Committee on Data Exchange (pdf 0.04 Mb) Reports of Sections, Working and Study Groups Section on Ecology of harmful algal blooms in the North Pacific (pdf 0.03 Mb) Section on Carbon and Climate Working Group 18 on Mariculture in the 21st century - The intersection between ecology, socio-economics and production (pdf 0.06 Mb) Working Group 19 on Ecosystem-based management science and its application to the North Pacific (pdf 0.03 Mb) Reports of the Climate Change and Carrying Capacity Program Implementation Panel on the CCCC Program (pdf 0.04 Mb) CFAME Task Team (pdf 0.04 Mb) MODEL Task Team (pdf 0.04 Mb) Reports of Advisory Panels Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (pdf 0.04 Mb) Advisory Panel on Marine Birds and Mammals (pdf 0.03 Mb) Advisory Panel on Micronekton Sampling Inter-Calibration experiment (pdf 0.05 Mb) Summary of Scientific Sessions and Workshops (pdf 0.2 Mb) Membership List (pdf 0.07 Mb) List of Participants (pdf 0.07 Mb) List of Acronyms (pdf 0.03 Mb)