The Fish Industry—Toward Supply Chain Modeling

Mathematical models for simulating and optimizing aspects of supply chains such as distribution, planning, and optimal handling of raw materials are widely used. However, modeling based on a holistic chain view including several or all supply chain agents is less studied, and food-related aspects such as quality and shelf-life issues enforce additional requirements onto the chains. In this article, we consider the supply chain structure of the fish industry. We discuss and illustrate the potential of using mathematical models to identify quality and value-adding activities. The article provides a first step toward innovative supply chain modeling aimed to identify benefits for all agents along chains in the fish industry.     

The reproductive cycle of the ‘blunt’ sea urchin

The reproductive cycle of the blunt sea urchin, Sphaerechinus granularis (Lamarck), was studied in the Bay of Brest, West Brittany, from monthly samples by examining seasonal changes in gonadal index, in the stages of gonad development and in oocyte diameters. This echinoid exhibited an annual cycle of gonadal growth, with a short breeding season occurring in May and June, and a decrease in gonadal index during the winter attributed to the use of nutrient resources. Histological examinations defined long mature stages during autumn, winter and early spring, where the vitellogenic oocytes accumulated in the lumen of the gonad. Changes in oocyte diameters showed a short pre-spawning period in April and May. The brief breeding season was followed by rapid post-spawning recovery and gonad growing stages during the summer, where the gonads mainly grew through the development of nutritive tissue. The features of this reproductive cycle show that the species can be commercially exploited and these results are used to make recommendations in terms of the management of S. granularis fisheries in Brittany. The influence of temperature on the initiation of spawning was noted again. This exogenous factor could be monitored to improve gonad production and availability of mature gametes in mariculture projects. © Rapid Science Ltd. 1998     

The lake at Llandrindod Wells—a restoration comedy?

• 1. The lake at Llandrindod Wells, Wales, UK, is a typical urban shallow lake. Created in the 19th century for amenity, it has a long history of management for various, often conflicting, purposes. After the 1950s, the once clear water became turbid with phytoplankton, and aquatic plants became very scarce.
• 2. The most likely reason for this was introduction of common carp, for angling, into a fish community that contained no piscivores. Mobilization of phosphorus from the sediments by activities of the fish led to severe internal phosphorus loading, culminating ultimately in a requirement to close the lake, temporarily in summer, to water contact activities, because of a risk of toxic cyanophyte blooms.
• 3. The lake‐owners decided to restore the lake to greater amenity and conservation value by biomanipulation of the fish community and associated works. The restoration was successful in restoring clear water and plant communities, but because of the nature of the plants reintroduced, there were new problems of dense plant growth. Ownership of the lake then changed and, in a somewhat confused situation, the lake has been returned to a carp fishery.
• 4. Documents on the history of management of the lake, and available limnological data, are reviewed in relation to a general strategy for lake restoration and general lessons are drawn for future restoration projects.

Copyright © 2002 John Wiley & Sons, Ltd.     

The financial feasibility of small‐scale grouper aquaculture in the Philippines

Abstract

This paper presents the results of an economic analysis of the aquaculture of two species of grouper E. coloides (orange‐spotted grouper, green grouper, red‐spotted grouper) and E. malabaricus (malabar grouper, black‐spotted grouper) for small producers in the Philippines. The findings of the analysis indicate that, based on the assumptions, grouper culture is financially feasible. However, the capital requirements for the broodstock, hatchery/nursery, and integrated system may be beyond the financial means of many small producers. These stages of grouper culture may need to be developed as a larger project by private investors or government. The capital investment requirement for grow‐out (not including purchase of transport boxes) is within the financial means of small producers. Loans or other incentives will need to be made available for the small producer, but the cash flow indicates that these loans can be repaid in the first year of production.     

The teleost pseudobranch: a role for preconditioning of ocular blood supply?

The physiological relevance of the teleost pseudobranch as a remnant of a reduced gill arch is still unclear. Numerous hypotheses have been proposed regarding its physiological role, but direct confirmatory evidence is lacking. The close relationship by serial blood flow arrangement with the fish eye’s choroid rete has sparked the idea that pseudobranchial preconditioning of blood pH may facilitate initiation of the Root effect and thus support the establishment of high oxygen tensions for retinal diffusive supply. This idea was critically tested by studies on isolated pseudobranchs in situ (Oncorhynchus mykiss), perfused with RBC/Ringer or RBC/plasma suspensions of widely varied composition (pH 7.4–8.2). Detailed analysis of inflowing as compared to effluent perfusates indicated normal aerobic metabolism expressed by a rise in Pco₂ (+0.39 ± 0.13 mmHg ), an oxygen utilization of 25% and a high oxygen consumption of ∼400 nmol g⁻¹ min⁻¹. Upon passage of the pseudobranch, pH (corrected for Haldane effect) was only slightly acidified (−0.03 to −0.10), [HCO₃ ⁻] and [lactate] were slightly enhanced (+0.51 mmol l⁻¹ or 0.13 mmol l⁻¹, respectively). In order to test for yet unknown plasma components involved in pseudobranch function, a second series of experiments was conducted using RBC-suspensions in fresh plasma instead of Ringer, with results closely resembling those of the RBC/Ringer series. Lacking any physiologically significant correlation with the level of perfusate pH, the obtained data indicate pseudobranchial basic metabolic activity rather than pH regulatory characteristics. Also the observed absolute changes in pH are negligible in terms of pH regulation towards the Root-threshold. Accordingly, the present experiments as well as plausibility evaluation of mechanisms do not support the idea of blood pH pre-adjustment prior to entry into the choroid rete structure of the teleost eye to facilitate the Root-mediated oxygen release.     

The aquarium hobby: can sinners become saints in freshwater fish conservation?

The aquarium hobby is popular worldwide, but it has positives and negatives for freshwater fish conservation. The most damaging impacts of the aquarium trade on ecosystems are overharvesting and invasive species. Consequently, many conservationists and academics have the perception that aquarium hobbyists are generally harmful to species conservation. Without overlooking these major drawbacks of the aquarium hobby, we aim to establish common ground between hobbyists and conservationists by correcting some misconceptions and showing the benefits of serious aquarium hobbyists in the conservation of freshwater fishes and their habitats. Our overview illustrates that the aquarium hobby is not insensitive to the pernicious effects of this enduring hobby on natural systems and that serious aquarists and their associations can directly assist and fund scientific research, increase conservation awareness among the general public and even participate in ex situ and in situ conservation programmes for native fish species at national or international levels. Whilst the relationship between conservationists and the aquarium hobby has often been antagonistic in recent years, ultimately most biologists and aquarists share a love of the species they study or maintain, and this common interest could be the basis for a more positive and productive relationship.     

The value of recreational fishing in Sweden – Estimates based on a nationwide survey

A nationwide recreational fishing survey in Sweden was used to estimate the benefits of recreational fishing in Sweden. The survey targeted the Swedish population and, consequently, the sample contained a large fraction of zero fishing days. To consider this, a zero-inflated Poisson model was used in the estimations. Swedes fished about 15.6 million days in 2013, of which two-thirds were spent on inland fishing, and one-third on marine and coastal fishing. Expected consumer surplus per fishing day varied with the season; SEK 193 for winter fishing, SEK 787 for summer fishing and SEK 95 for autumn fishing. Although about 70 per cent of total fishing days were spent on inland fishing, the weighted consumer surplus per fishing day in marine and coastal areas were higher. The results also demonstrated strong positive effects of increases in expected catch per day on number of fishing days demanded and consumer surplus, which have important implications for fishery policies directed at recreational fishing.     

The cooperation between the Chinese Bureau of Fisheries and the Norwegian Directorate of fisheries

Activities1994In 1994 Peter Gullestad(Present Director General of Fisheries in Bergen) headed a Norwegian delegationvisiting China.In his presentation of“The N orwegian exp erience in fisheries management and control” - hestressed the fact that overcapacity is“the root of all evil”.He also underlined that it is important not only toset up a legal system for fisheries management but also to establish reliable catch statistics.He further morepointed out that good scientific advice is th…     

Fisheries Oceanography: The first 30 years and new challenges in the 21st century

The journal Fisheries Oceanography provides a global forum for fisheries scientists and oceanographers to understand how marine ecosystems, and the services they provide to society, are structured and shaped by environmental variability and climate change. With this special issue, as well as the 30th Anniversary Virtual Issue of the most influential papers from the journal's history, we commemorate 30 years of publishing leading research in the field of fisheries oceanography. These issues showcase the extent, depth and impact of the research published in Fisheries Oceanography. We also reflect on the evolution of research themes through the journal's history, and highlight key emergent themes in our field. We look forward to continuing to publish impactful research in the pages of Fisheries Oceanography in the years ahead.     

The effect of α-MSH treatment on the hypothalamic-pituitary-gonad axis in the cichlid fish Oreochromis mossambicus

Fish Physiology and Biochemistry - In this investigation, we examined the influence of alpha-melanocyte stimulating hormone (α-MSH), a proopiomelanocortin-derived peptide, along the...     

Understanding and valuing conflicts in marine protected areas: The best way to develop innovations?

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The modified Johnson-Reid method--a practice model for coccidiosis monitoring in the fattening of young fowl?

Models of coccidiosis-monitoring known from literature are described. A suitable alternative of determining the coccidia status in a broiler population is the "modified Johnson-Reid method". This method makes a standardization of diagnostic finding and evaluation possible as well as a differentiated intestinal localization and the determination of coccidia incidence severity. In addition to the microscopic screening of the caecum contents--as described by Johnson-Reid--it appears necessary to take also swabs from parts of the duodenum and jejunum (near the Meckel's diverticulum). Subsequently this method is an important help for veterinarians working with broiler production, for diagnostic institutions as well as producers of anticoccidial agents, especially in regard to its documentation rate and the resulting consequences. In this way other diagnostic efficiency data in broiler production are significantly completed.     

Can a cow save a newt? The role of cattle drinking troughs in amphibian conservation

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Why is the antibody response of Atlantic cod so poor? The search for a genetic explanation

ABSTRACT:   The immune system of the Atlantic cod ( Gadus morhua L) is unusual in that it cannot produce a specific antibody response upon immunization. Despite this, the cod is not particularly susceptible to infectious disease in its normal environment. This review examines the potential genetic basis for the lack of a specific antibody response in the cod. The genetics of cod immunoglobulins are compared with those of other well-characterized teleost fish. A review of the evidence suggests that deficiencies in the number, structure, organization, diversity and expression of both Immunoglobulin (Ig) heavy and Ig light chain genes in cod cannot explain its unusual antibody response. It is concluded that a deficiency in cod major histocompatibility (MH) class II molecules is a prime suspect for the lack of a specific antibody response in cod, and that testing of this hypothesis must await future experimentation.     

Small-Scale Shrimp Grower–Collector Relationships: The Case of Thua Thien Hue Province,Central Vietnam

Small-scale shrimp-culture is an important livelihood for rural residents in Thua Thien Hue (TTH) province, central Vietnam. However, they are facing the risk of exclusion from the food system due to globalization and trade liberalization. To keep these farmers in modern supply chains, their relationships with other chain actors, foremost the collectors, need to be improved. Thus, this study explores the characteristics and constructs of the relationships between the small-scale shrimp growers and their collectors. Data was based on a survey on 83 small-scale shrimp growers, together with 16 unstructured interviews with growers (10) and collectors (6). It was revealed that the relationships between small-scale shrimp growers and collectors in TTH province are short-term and price-driven and are influenced by the power of collectors. The relationship strength was measured by five intercorrelated constructs including reliability, willingness-to-maintain, desire-fulfilment, negotiation capacity, and discussion capacity. Although some constructs were positively correlated, the strength of the relationships was weak. Both business linkages and social connections affected the grower-collector relationships. Female traders had stronger relationships with collectors than males. Therefore, interventions should be focused on business and social linkages as well as females’ involvement in shrimp trade.     

The European Water Framework Directive: a new era in the management of aquatic ecosystem health?

1. The forthcoming European Commission Water Framework Directive will introduce catchment management throughout Europe, and could have major impacts on the conservation and restoration of aquatic ecosystems. The Directive is outlined, and the proposed mechanisms for determining water quality status under the Directive are described. 2. The Directive is assessed using the developing ideas of ecosystem health. These combine scientific validity with an open acknowledgement of the value judgements inherent in all assessments of ecological quality, and emphasize the importance of public involvement. 3. Permitted derogations and exemptions are identified and their likely consequences discussed. These include substantial reductions in the potential of the Directive to improve water status in some cases. Existing bioassessment methods relevant to the proposed scheme are reviewed, and the sampling and statistical implications of the Directive are explored. Much work is needed on the development of ecological classification and referencing systems if the requirements of the Directive are to be met. 4. The emphasis of the Directive on biological (and not just chemical) quality goals, and the introduction of a consideration of ecological functioning (as well as structure) is welcomed. Although the Directive requires the assessment of hydromorphological and chemical, in addition to biological, variables, in most cases biological assessment is given priority. We advocate inclusion of all three elements in quality assessments. 5. The Directive gives little advice on policy integration for catchment management at European and national levels, and fails to provide for public involvement in the process of ecosystem management. These omissions will limit the ability of the Directive to deliver ecosystem health, and need to be addressed if the goals of the Directive are to be achieved. © 1998 John Wiley & Sons, Ltd.     

Does upwelling intensity determine larval fish habitats in upwelling ecosystems? The case of Senegal and Mauritania

European sardine (Sardina pilchardus) and round sardinella (Sardinella aurita) comprise two‐thirds of total landings of small pelagic fishes in the Canary Current Eastern Boundary Ecosystem (CCEBE). Their spawning habitat is the continental shelf where upwelling is responsible for high productivity. While upwelling intensity is predicted to change through ocean warming, the effects of upwelling intensity on larval fish habitat expansion is not well understood. Larval habitat characteristics of both species were investigated during different upwelling intensity regimes. Three surveys were carried out to sample fish larvae during cold (permanent upwelling) and warm (low upwelling) seasons along the southern coastal upwelling area of the CCEBE (13°–22.5°N). Sardina pilchardus larvae were observed in areas of strong upwelling during both seasons. Larval habitat expansion was restricted from 22.5°N to 17.5°N during cold seasons and to 22.5°N during the warm season. Sardinella aurita larvae were observed from 13°N to 15°N during cold seasons and 16–21°N in the warm season under low upwelling conditions. Generalized additive models predicted upwelling intensity driven larval fish abundance patterns. Observations and modeling revealed species‐specific spawning times and locations, that resulted in a niche partitioning allowing species' co‐existence. Alterations in upwelling intensity may have drastic effects on the spawning behavior, larval survival, and probably recruitment success of a species. The results enable insights into the spawning behavior of major small pelagic fish species in the CCEBE. Understanding biological responses to physical variability are essential in managing marine resources under changing climate conditions.