Mitsutaku Makino

Fishery management in Japan

There are few legal marine protected areas in Japan rather than fishing-ban areas. Fishers did not seek legal fishing-ban areas but they did establish fishing-ban areas by autonomous bases. We briefly introduce the institutional history and features of Japanese coastal fishery management, including the past decade’s major legislative developments. Japan still has a decentralized co-management system involving fishers and the government, and ca. 98% of Japanese fishers are artisanal. There are several successful cases of coastal fisheries management in Japan. However, offshore industrial fisheries have problems in Japan. We compare coastal fisheries co-management between Japan and Chile. We finally discuss the possibility of improvement for Japanese fisheries.

A guideline for ecological risk management procedures

A practical guideline for community-level ecological risk management is proposed, with particular emphasis on the mutual interdependencies of the scientific analysis, public consensus building, and an adaptive management. The procedure we recommend spans the screening of potential ecological risks, the involvement of related stakeholders, the conceptual development from the “undesired event” over assessment endpoints to measures of effect and stress factors, the risk assessment for the no-action case, the planning phase from the public decision to become active and the setting of goals over a specification of monitoring and control methods to an assessment of feasibility and a public approval of the management plan and finally the adaptive management from initiation over continued monitoring to revisions of the plan, if required. The procedure contains several checkpoints, alternative routes, and possibilities to correct previous decisions.

Towards integrated research in fisheries science

In this paper we present a call for a re-directing fisheries science towards an integrated scientific activity which includes the trajectory of fish from eggs and their life underwater to consumption on the table. We propose that integrated research in fisheries science be defined as “interdisciplinary research for society and human well-being which deals with the sustainability of dynamic fisheries systems, taking various knowledge, values, and needs into account.” As an integrative discipline, fisheries science offers many advantages to overcoming the limitations of the traditional sciences. The ability to conduct traditional research activities based on each academic discipline is a prerequisite to participating in integrated research. However, “additional processes” are needed, such as the introduction of new integrated thinking, joint determination of the research framework, mutual learning by participating researchers, interaction with stakeholders, among others. Integrated research in fisheries science would allow overall influences to be analyzed, including exogenous factors such as environmental changes and other marine industries. Walleye pollock Theragra chalcogramma provides a good model species for analyzing future scenarios of the structure of the industry as well as potential strategies for addressing and considering the effects of other highly fluctuating resources. One of the most challenging topics is identifying possible paths from a depleted stock to its future recovery. Scientific analyses on “How fast?” “Who should bear the costs?” “When it will occur”, etc., should be conducted by close interactions with stakeholders.

Application of the coastal ecosystem complex concept toward integrated management for sustainable coastal fisheries under oligotrophication

Harmonizing coastal fisheries with water-quality improvement has become an essential factor for the sustainable use of coastal ecosystem services. Here, we present the scope of our study based on an interdisciplinary approach including ecological actions, socio-economic actions and socio-psychological actions. We chose to focus on the interaction between oyster aquaculture and seagrass vegetation as a typical ecological action using the coastal ecosystem complex (CEC) concept. Coastal organisms have adapted their traits to the environment over a long period of time, so that restoration of the CEC represents reconstruction of the original process of coastal production. Subtidal seagrass vegetation with intertidal oyster reefs is the original CEC in Japan, which would be expected to enhance coastal production by improving the production efficiency without adding nutrients. A simple field experiment examining carbon and nitrogen contents and stable isotope ratios revealed that oyster spats cultivated on a tidal flat adjacent to seagrass beds had higher nitrogen contents and higher δ13C ratios than spats cultivated in an offshore area using only pelagic production. This result suggests that utilization of the CEC, which enables oysters to use both pelagic and benthic production, has potential to sustain a food provisioning service for humans, even in oligotrophic conditions.

TSUNAGARI: a new interdisciplinary and transdisciplinary study toward conservation and sustainable use of biodiversity and ecosystem services

The expanding economical activities have accelerated losses of biodiversity and ecosystem services, which are especially pronounced in Asia. To find solutions to stop these losses, a group of scientists studying both ecological and social sciences has launched an interdisciplinary research network, entitled TSUNAGARI (Trans-System, UNified Approach for Global and Regional Integration of social-ecological study toward sustainable use of biodiversity and ecosystem services). The project is based on two main perspectives: (1) integrating different disciplines of environmental research across multiple spatial scales, and (2) evaluating the importance of ecosystem connectivity between land and ocean for biodiversity and ecosystem services. The integrative studies have been started as follows: (1) integrating global-scale analyses of biodiversity and economy by developing GIS-based footprint analysis, (2) establishing the link between the studies of local good practices of ecosystem management and life cycle assessment on ecosystem good and services, (3) linking local-scale ecosystem studies to decision making processes for sustainable society by multiple stakeholders, and (4) upscaling local analyses of ecosystem processes to broad-scale analyses of ecosystem patterns. The proposed approaches are considered effective to solve problems that impede conservation of biodiversity and sustainable use of multiple ecosystem services in various situations although we also find some gaps such as regional biases in biodiversity data and involvement of different types of stakeholders. By overcoming the major bottlenecks, we believe the new integrated approaches will promote conservation and sustainable management of biodiversity and ecosystem services research, and contribute to advance decision-making processes from local communities to international levels.

A transdisciplinary research of coastal fisheries co-management: the case of the hairtail Trichiurus japonicus trolling line fishery around the Bungo Channel, Japan

Under the coastal fisheries co-management regime in Japan, local fishers play important roles in deciding on and implementing local management measures. Therefore, using the case study of a hairtail trolling line fishery, we conducted a transdisciplinary research with fishers, processors, government officers, etc. Taking social and biological factors into account, we defined management criteria and targets (resource, economic, human community, and local food culture) in collaboration with local fishers. We chartered local fishing vessels to determine parameters that were easily understood by local fishers. We established a local consultative committee comprising fishers, processors, and distributors, and developed a fish distribution strategy to nurture the local hairtail food culture. The integrated effects of various management scenarios were evaluated by the operating model. We found that co-ordinated management by both the trolling line fishery and purse seiners in the neighbouring prefecture was required to achieve targets. Two realistic scenarios are recommended: a conservative scenario that could achieve targets even with few strong year classes, and an adaptive scenario that protects strong year classes, but relies on a higher frequency of these. We shared these results with the local fishers and government officers, which led to actual improvements in management measures.

Conservation of small hairtail Trichiurus japonicas by using hooks with large artificial bait: effect on the trolling line fishery

Overfishing has reduced the stock of hairtail Trichiurus japonicus around the Bungo Channel, Japan. To determine whether using larger bait in the trolling line fishery could avoid catching small/undersize hairtail, we developed and trialled a new large artificial bait (a soft plastic bait, 6 inches long). A traditional lure with natural bait (type-1), a new lure of the new artificial bait hook without natural bait (type-2), and a new lure with natural bait (type-3) were tested in fishing operations around the Bungo Channel. Compared with type-1, type-2 and type-3 caught fewer undersized and immature female individuals. The number of fish caught, yield, and composition of commercial size grades per recruitment were calculated from field data for each lure and compared. The catch sizes (number of fish per recruitment) were smaller for type-2 and type-3 than for type-1, but yield per recruitment was higher for type-3 than for type-1. Compared with type-1, type-2 and type-3 caught more large individuals, which are more valuable. The newly developed artificial bait conserves hairtail stocks by targeting larger fish, which is economically beneficial for the hairtail trolling line fishery.

Stock structure and resource management of hairtail Trichiurus japonicus based on seasonal broods around the Bungo Channel, Japan

Declines in landings of the hairtail Trichiurus japonicas indicate the need for more effective management of this species. Hairtail spawning peaks occur twice yearly in the Bungo Channel, in spring and autumn. Relationships between hairtail stock and brood seasonality were examined to determine if an association between either and a decline in landings existed. Stock assessments show that the biomass of both spring and autumn hairtail broods from within and around the Bungo Channel are decreasing, with a rapid reduction in spring-brood stock abundance after 2007 largely responsible for decreased landings. Yield and spawning per recruitment analyses indicate current fishing pressure to be higher than several reference points. We suggest that fishing pressure needs to be reduced by at least 20% of the current level for this fishery to remain sustainable, as the projected stock abundance and catch demonstrate that the current fishing pressure is unsustainable. Analysis of time-series data of recruits per spawning revealed spring-brood recruitment to have been strong in year classes 2003 and 2005. Of various options available for improved management of this fishery, we propose that fishing pressure should be reduced in the years following the appearance of strong year classes to increase future biomasses and landings.

Introduction: from the birth to the table of walleye pollock Theragra chalcogramma

Fisheries provide food, feedstuff, and materials which are reliant on ecosystem services provided by marine and freshwater systems. Fish spawn and mature in aquatic systems, from which they are harvested by fishers, distributed and processed in households, restaurants, or processing plants, and either eaten by consumers, used in aquaculture, horticulture or agriculture, or used in manufacturing. The movement of fish from sea to plate follows distinct sequential stages. We call this the “fisheries system”. While each stage of the fisheries system has been the focus of specific research activities, these activities have generally proceeded from the perspective of individual disciplines, e.g., oceanography, chemistry, biology, ecology, resource dynamics, economics, business management, food science, processing, nutrition studies, etc. As a result, their objectives, data, models, discussions, etc., do not present an effectively integrated perspective of the fisheries system as a whole. This Special Feature brings together research from across disciplines to provide a broad perspective of the walleye pollock Theragra chalcogramma fisheries system. While this falls short of being a fully integrated model, it highlights key interfaces among disciplines and illustrates fundamental research questions for each stage. By highlighting these questions and interfaces, we hope to foster an intellectual environment that will lead to true “integrated research” that can best be pursued by multi-disciplinary teams rather than by individual scientists who limit their research activities to the narrow scope of their specific disciplines.