Modern Fisheries Research Articles

Targeting Multiple Management Objectives in Sustainable Fisheries

Modern fisheries management must balance between return (economic value) and risk (harvest uncertainty and stock collapse). Management tools should target multiple simultaneous management objectives. These include output, number of seasons, total stock value and its uncertain fluctuations. I provide a stylized fishery model for simulating the outcomes of these competing management objectives under various regulatory and market environments. Results show that these objectives need not be mutually exclusive. They can be traded off gradually, quantitatively and transparently. The trade-offs involve profit and output versus job provision, employment security, stock conservation and less-risky harvesting. The pursuit of higher return must balance against the risk of stock collapse and harvest fluctuations.

Contemporary fisher images: Ideologies, policies and diversity

This paper presents survey results that document heterogeneity among contemporary Norwegian fishers and discusses the implications of such heterogeneity upon fisheries policies in general and recruitment policies in particular. With the help of Multiple Correspondence Analysis and fishers' discourses related to management and technology, a fisher typology is produced. This approach yields four types of fishers. Two types of fishers are closely linked to ideology and form a basis for modern fisheries management. The other two are not ideological figures, but more pragmatic, and deviate from the assumptions usually found in fisheries management. As governing is difficult without images, an ontological understanding of the fisher is necessary. Thus, our image of the fisher has to be revised and fisheries policies have to take into account the presence of a number of adaptations and rationalities; hence, a more diverse recruitment policy is called for.

The spectre of uncertainty in management of exploited fish stocks: The illustrative case of Atlantic bluefin tuna

The recent overexploitation of East Atlantic and Mediterranean bluefin tuna stock has been well documented in the media where it has become the archetype of overfishing and general mis-management. Beyond the public debate, the crisis also highlighted how the interactions between science and management can change through time according to the awareness of the public opinion. To reflect these issues, the history of Atlantic bluefin tuna overfishing is first described. Then, the major uncertainties that undermine the current scientific advice are summarized and the importance of reducing their impacts by improving knowledge and developing robust scientific framework is considered. The study also discusses how uncertainty was used by different lobbies to discredit science-based management. The recent improvement in bluefin tuna stock status following the implementation of the rebuilding plan shows that, despite uncertainty in the scientific advice, the management of a heavily exploited fish stock can be positive when there is a political will. However, optimizing long-term yields of modern fisheries implies good science. The study concludes by advocating for the implementation of a scientific quota that should be part of the management framework to support the scientific advice.

Correction: High Potential for Using DNA from Ancient Herring Bones to Inform Modern Fisheries Management and Conservation

Correction: High Potential for Using DNA from Ancient Herring Bones to Inform Modern Fisheries Management and Conservation

Correction: High Potential for Using DNA from Ancient Herring Bones to Inform Modern Fisheries Management and Conservation

Correction: High Potential for Using DNA from Ancient Herring Bones to Inform Modern Fisheries Management and Conservation

Territoriality as a Driver of Fishers' Spatial Behavior in the Northumberland Lobster Fishery

Knowledge of informal rules governing fishers' behavior is important to help formulate policies suited to local conditions and supported by resource users. Fishers' behavior may be influenced by informal property rights or territoriality, yet drivers of such behavior in UK fisheries have seldom been explored. This study presents findings from interviews with lobster fishers (n = 44) at six ports in Northumberland, UK. The study aimed to investigate the existence, importance, and drivers of territoriality in this fishery, contributing to the debate over whether informal rules and norms may benefit modern fisheries management. The findings showed evidence of group territorial behavior based more on social norms than on economic calculations, but declining in response to changes in fleet structure, technological developments, legal sanctions, and community cohesiveness. Territoriality was being replaced by a new norm of “first come first served”; if this norm fails, spatial planning regulations may need to be introduced.

Changes in size and age at maturity of the northern stock of Tilefish (Lopholatilus chamaeleonticeps) after a period of overfishing

The modern fishery for Tilefish (Lopholatilus chamaeleonticeps) developed during the 1970s, offshore of southern New England, in the western North Atlantic Ocean. The population quickly became over exploited, with documented declines in catch rates and changes in demographic traits. In an earlier study, median size at maturity (L50) of males declined from 62.6 to 38.6 cm fork length (FL) and median age at maturity (A50) of males declined from 7.1 to 4.6 years between 1978 and 1982. As part of a cooperative research effort to improve the data-limited Tilefish assessment, we updated maturity parameter estimates through the use of an otolith aging method and macroscopic and microscopic evaluations of gonads. The vital rates for this species have continued to change, particularly for males. By 2008, male L50 and A50 had largely rebounded, to 54.1 cm FL and 5.9 years. Changes in female reproductive schedules were less variable among years, but the smallest L50 and youngest A50 were recorded in 2008. Tilefish are dimorphic, where the largest fish are male, and male spawning success is postulated to be socially mediated. These traits may explain the initial rapid decline and the subsequent rebound in male L50 and A50 and less dramatic effects on females. Other factors that likely contribute to the dynamics of maturity parameter estimates are the relatively short period of overfishing and the amount of time since efforts to rebuild this fishery began, as measured in numbers of generations. This study also confirms the gonochoristic sexual pattern of the northern stock, and it reveals evidence of age truncation and relatively high proportions of immature Tilefish in the recent catch.

Traditional fishing rights: analysis of state practice

The recognition of traditional fishing rights is a major legal and policy issue in modern fisheries law at two levels. The first is at a purely domestic level relating to the legal recognition of traditional rights. The second level arises from the implication of the United Nations Convention on the Law of the Sea 1982 (LOSC) that has resulted in extended coastal jurisdiction over marine living resources. One consequence of the LOSC is that areas previously fished by nationals of other States have now come under the sovereignty and sovereign rights of the adjacent or opposite coastal State; necessitating legal arrangements to ensure the continuation and management of such rights. This paper analyses the types and classification of traditional fishing rights, issues and problems, as well as the state practice of traditional fishing rights that are guaranteed by one State to the nationals of another State.

The research on key technology and intelligent equipment of aquaculture welfare in industrial circulating water mode

The establishment of aquaculture welfare in circulating water system,based on fishery welfare concept and the characteristics of closed circulating w ater system of aquaculture,has become a strategic need to promote the sustainable development of modern fishery in China. In this paper,the impact factors of w elfare in circulating w ater system,intensive demands and scientific evaluation standards of aquaculture w elfare in circulating w ater system w ere analyzed and discussed. The contents of this paper refer to the key technology in circulating w ater system,cross merging advanced information technology and automatic control technology. The purpose of this paper is to provide theoretical and technical support to set up the criterion of production process control,establish security mechanism in aquaculture w elfare,and truly improve quality and safety level of aquacultural product in the future.

A step-by-step framework to assess benefits of established temperate marine protected areas

Marine protected areas (MPAs) have been advocated as a solution to the challenges of both conservation and modern fishery management, but their application remains controversial, partly because there are only general guidelines for evaluating their effectiveness. We propose a framework to specifically evaluate established MPAs in six steps. We tested the approach by reviewing published research and unpublished information on the Goukamma MPA in the centre of the South African temperate south coast. Information reviewed included effects on the structure of fish populations, catch and abundance indices of fish species, and ecosystem effects. We investigated factors that determine the usefulness of a MPA in fisheries management, including the movement behaviour of adult fishes, larval dispersal and fisher-displacement patterns. We found that differences in the rates of exploitation across the MPA border resulted in differences in abundance, size and condition of the main target species, roman (Chrysoblephus laticeps). The diversity and abundance of non-target fish species, and the composition of the benthic invertebrate community, were affected by the cessation of fishing. The potential for ‘spillover’ of adult roman might be limited to the vicinity of the MPA by their small home range, but there is potential for self-seeding and dispersal of roman eggs and larvae over wider areas. These theoretical considerations were confirmed by an analysis of catch data from before and after MPA implementation. The framework presented here may help to identify and fill gaps in the knowledge of established MPAs along South Africa’s temperate south coast.

High potential for using DNA from ancient herring bones to inform modern fisheries management and conservation.

Pacific herring (Clupea pallasi) are an abundant and important component of the coastal ecosystems for the west coast of North America. Current Canadian federal herring management assumes five regional herring populations in British Columbia with a high degree of exchange between units, and few distinct local populations within them. Indigenous traditional knowledge and historic sources, however, suggest that locally adapted, distinct regional herring populations may have been more prevalent in the past. Within the last century, the combined effects of commercial fishing and other anthropogenic factors have resulted in severe declines of herring populations, with contemporary populations potentially reflecting only the remnants of a previously more abundant and genetically diverse metapopulation. Through the analysis of 85 archaeological herring bones, this study attempted to reconstruct the genetic diversity and population structure of ancient herring populations using three different marker systems (mitochondrial DNA (mtDNA), microsatellites and SNPs). A high success rate (91%) of DNA recovery was obtained from the extremely small herring bone samples (often <10 mg). The ancient herring mtDNA revealed high haplotype diversity comparable to modern populations, although population discrimination was not possible due to the limited power of the mtDNA marker. Ancient microsatellite diversity was also similar to modern samples, but the data quality was compromised by large allele drop-out and stuttering. In contrast, SNPs were found to have low error rates with no evidence for deviations from Hardy-Weinberg equilibrium, and simulations indicated high power to detect genetic differentiation if loci under selection are used. This study demonstrates that SNPs may be the most effective and feasible approach to survey genetic population structure in ancient remains, and further efforts should be made to screen for high differentiation markers.This study provides the much needed foundation for wider scale studies on temporal genetic variation in herring, with important implications for herring fisheries management, Aboriginal title rights and herring conservation.

QUANTITATIVE METHODS FOR DECISION SUPPORT IN THE ICELANDIC FISHING INDUSTRY

Abstract Modern fisheries already collect vast amount of data, for example, through ERP systems and electronic log‐books. It is however well known that the data are rarely used for improving operational decision making. By converting this data into useable information, decision making in the fishing industry could be improved. This paper attempts to show that quantitative methods can be of use in many aspects of decision making in the fishing industry. The paper proposes a hierarchically structured decision support process based on two different optimization models for supporting the long‐ and short‐term decision making in fisheries. For long‐term planning the paper proposes a linear optimization model that describes the entire operation of a vertically integrated seafood company. For short‐term decision making the paper proposes a mixed integer linear optimization model to assist in organizing vessel trips and deciding catch location with regard to raw material quality and yield obtained in processing.

Major Retailing Logistics Management Mechanisms

Due to the emergence of the global economy and increased competition, many of the modern fishing companies have recognized that their fisheries rapid product introduction and service innovation to market the importance of supply chain management. To improve their competitiveness, many modern fishing companies have accepted supply chain management to improve organizational effectiveness and achievement of organizational objectives, increase customer value, better use of resources, and improve profitability. Consider adhere to enterprise operational efficiency to improve collaboration and client response in the modern fisheries management advocated by business partners, an additional thrust towards a successful competitive strategy. Supply chain management in the fisheries industry has become part of the agenda of the senior management of the fishery production and the retail industry. Appropriate mechanism to optimize fisheries logistics supply chain design and effective fisheries management method is a reference to the fisheries in this article the major retail logistics supply chain management. Soft computing technology based on the proposed new program, and effectively solve the problems by a variety of dynamic segment of the logistics supply chain of the fisheries of the major retail companies.

Ancient history of flatfish research

Owing to both their special appearance and behavior flatfish have attracted the special attention of people since ages. The first records of humans having been in touch with flatfish date back to the Stone Age about 15,000yearsB.C. Detailed descriptions were already given in the classical antiquity and were taken up 1400years later in the Renaissance by the first ichthyologists, encyclopédists, and also by practical men. This was more than 200years before a number of common flatfish species were given their scientific names by Linnaeus in 1758. Besides morphology, remarkable and sometimes amusing naturalistic observations and figures are bequeathed. Ancient history of flatfish research is still a wide and open array. Examples are presented how the yield of information and interpretation from these times increases with interdisciplinary cooperation including archeologists, zoologists, ichthyologists, historians, art historians, fisheries and fishery biologist. The timeline of this contribution ends with the start of modern fishery research at the end of the 19th century in the course of the rapidly increasing exploitation of fish stocks.

Stable Isotope Evidence for Late Medieval (14th–15th C) Origins of the Eastern Baltic Cod (Gadus morhua) Fishery

Although recent historical ecology studies have extended quantitative knowledge of eastern Baltic cod (Gadus morhua) exploitation back as far as the 16th century, the historical origin of the modern fishery remains obscure. Widespread archaeological evidence for cod consumption around the eastern Baltic littoral emerges around the 13th century, three centuries before systematic documentation, but it is not clear whether this represents (1) development of a substantial eastern Baltic cod fishery, or (2) large-scale importation of preserved cod from elsewhere. To distinguish between these hypotheses we use stable carbon and nitrogen isotope analysis to determine likely catch regions of 74 cod vertebrae and cleithra from 19 Baltic archaeological sites dated from the 8th to the 16th centuries. δ13C and δ15N signatures for six possible catch regions were established using a larger sample of archaeological cod cranial bones (n = 249). The data strongly support the second hypothesis, revealing widespread importation of cod during the 13th to 14th centuries, most of it probably from Arctic Norway. By the 15th century, however, eastern Baltic cod dominate within our sample, indicating the development of a substantial late medieval fishery. Potential human impact on cod stocks in the eastern Baltic must thus be taken into account for at least the last 600 years.

The Tragedy of Our Legacy: How do Global Management Discourses Affect Small Scale Fisheries in the South?

Modern fisheries management discourse is supported by two fundamental narratives that have global impacts. One is the fear of open access regimes, and the other is the condemnation of catching under-sized and immature fish. These narratives have existed for more than half a century and originate from the common property theory and the maximum yield per recruit theory. Our aim is to critically discuss and evaluate these narratives which have been developed within the context of scientific management of single-species industrial fisheries. We will show that the underlying assumptions can be seriously wrong and particularly absurd in fluctuating multi-species, multi-gear artisanal fisheries. Fishing effort in small scale fisheries is often largely regulated by natural production, like other top predators, and many targeted fish stocks and fish communities display a high degree of resilience. Furthermore, in spite of common belief, small scale unregulated, non-selective, adaptive fishing patterns could be healthier and far more ecosystem conserving than the current imposed single species management strategies. Many of these fisheries are serving as a ‘social security system’ – a common good and thereby function as a ‘last resort’ for economic mishap. Limiting open access will undermine the role of small scale fisheries to provide insurance, particularly for the poorest and least advantaged. The immense pressure to adapt to modern fisheries management thinking and economic theory is based on flawed assumptions and will not only have negative social effects, but also negative biological effects.

Global Sushi: The Political Economy of the Mediterranian Bluefin Tuna Fishery in the Modern Era

The bluefin tuna fishery in the Mediterranean has a long history of human interaction. In recent times, this fishery has become the central source of bluefin tuna for core nations, particularly Japan. This process was set off in large part by the growth of global fish markets, driven by the valuable sushi and sashimi market, and overfishing of other bluefin stocks in other parts of the world. The transformation of this fishery from an artisanal trap fishery to a globalized industrial fishery has had a number of social and environmental consequences. Based on in-depth fieldwork and historical research, this paper examines the political economy of the bluefin tuna fishery in the Mediterranean, with a focus on Sicily. It provides a descriptive history of the changing conditions in this fishery, paying special attention to the modern fishery. This research contributes to the discussions regarding the globalization and industrialization of agri-foodsystems and environmental degradation.

Comparison of Modern and Historical Fish Catches (AD 750-1400) to Inform Goals for Marine Protected Areas and Sustainable Fisheries

We tested the unsustainable fishing hypothesis that species in assemblages of fish differ in relative abundance as a function of their size, growth rates, vagility, trophic level, and diet by comparing species composition in historical bone middens, modern fisheries, and areas closed to fishing. Historical data came from one of the earliest and most enduring Swahili coastal settlements (approximately AD 750-1400). Modern data came from fisheries near the archeological site and intensively harvested fishing grounds in southern Kenya. The areas we sampled that were closed to fishing (closures) were small (<28 km(2) ) and permanent. The midden data indicated changes in the fish assemblage that are consistent with a weak expansion of fishing intensity and the unsustainable fishing hypothesis. Fishes represented in the early midden assemblages from AD 750 to 950 had longer life spans, older age at maturity, and longer generation times than fish assemblages after AD 950, when the abundance of species with longer maximum body lengths increased. Changes in fish life histories during the historical period were, however, one-third smaller than differences between the historical and modern assemblages. Fishes in the modern assemblage had smaller mean body sizes, higher growth and mortality rates, a higher proportion of microinvertivores, omnivores, and herbivores, and higher rates of food consumption, whereas the historical assemblage had a greater proportion of piscivores and macroinvertivores. Differences in fish life histories between modern closures and modern fishing grounds were also small, but the life histories of fishes in modern closures were more similar to those in the midden before AD 950 because they had longer life spans, older age at maturity, and a higher proportion of piscivores and macroinvertivores than the modern fisheries. Modern closures and historical fish assemblages were considerably different, although both contained species with longer life spans.

International workshop on opportunities for ecosystem approaches to fisheries management in the Pacific Ocean tuna fisheries

Modern fisheries management encompasses ecosystem-wide perspectives, and sustainability is measured both in terms of the target stocks but also in terms of the direct and indirect impact that fishing practices may have upon populations of non-target, associated and dependent species and ecosystem structure and function (Garcia and Cochrane 2005). Implementing an Ecosystem Approach to Fisheries Management (EAFM) requires performance measures against criteria that can be used to assess overall ecosystem status, the impacts of human activities, and environmental variation. In single-species management these decision criteria are quantitative measures primarily based on stock assessment model outcomes which can guide management. Analogous decision criteria for non-target and ecosystem-level attributes are in a nascent stage of development (Samhouri et al. 2010). There is increasing effort by a range of organizations to collect detailed data on the structure and dynamics of the Pacific Ocean pelagic ecosystem. This has primarily occurred through observer programmes (e.g. bycatch composition and quantities), trophic ecology (e.g. stomach contents, stable isotopes), and mid-trophic level sampling (e.g. acoustics and net sampling of micronekton and zooplankton). Tuna fisheries from the tropical Pacific Ocean (Fig. 1) provide more than 50% of the global catch, and applying EAFM is explicit in the conventions of the Regional Fisheries Management Organisations (RFMOs) responsible for their management. The Global Environment Facility Oceanic Fisheries Management project recently brought together scientists who have been leading ecosystem research in the Pacific Ocean pelagic systems, by convening a workshop to synthesize past progress and identify future priorities within the scientific and monitoring component of EAFM. The workshop was hosted by the Secretariat of the Pacific Community at its headquarters in Noumea, New Caledonia in March 2011.

An In Situ, Individual-Based Approach to Quantify Connectivity of Marine Fish: Ontogenetic Movements and Residency of Lingcod

As modern fishery assessments change in an effort to be more accurate and encompass the range of potential ecosystem interactions, critical information on the ecology of species including life history, intra and inter-specific competitive interactions and habitat requirements must be added to the standard fishery-dependent and independent data sets. One species whose movements and habitat associations greatly affects exploitation patterns is lingcod, Ophiodon elongatus, which support an economically important fishery along the coastal waters of the Pacific Coast of North America. High site fidelity and limited movements within nearshore areas are hypothesized to have resulted in high catchability, a major factor that has contributed to overfished stocks. Thus, assessing the level of movement and connectivity among lingcod subpopulations inhabiting nearshore habitats is a prerequisite to determining the condition of lingcod stocks. We used the Pacific Ocean Shelf Tracking (POST) Project acoustic receiver array in Alaska's Prince William Sound to monitor movements and residency of 21 acoustic-tagged lingcod for up to 16 months. Eight of sixteen lingcod (50%) initially aged at 2.5- to 3.5- years-old dispersed from their tag site. Dispersal was highly seasonal, occurring in two, five-week periods from mid-December through January and from mid-April through May. Dispersal in winter may be related to sexually immature lingcod or newly-mature male lingcod being displaced by territorial males. Spring dispersal may be indicative of the onset of migratory behavior where lingcod move out into Prince William Sound and possibly the offshore waters of the Gulf of Alaska. Our results reveal a pattern of ontogenetic dispersal as lingcod approach 4-years-old and exceed 50 cm total length. The large proportion of tagged fish migrating out of Port Gravina, their tagging site, reflects a high level of connectivity among Prince William Sound subpopulations. Our results also support the hypotheses that these subpopulations may be highly susceptible to overfishing because most fish show long residence times.