A number of artificial reefs has been constructed in many coastal areas of Japan to enhance coastal fisheries. They can improve the productivity but also protect and recover fish habitats, as well as preserve and nurture fishery resources. New methods are required to assess the impact of artificial reefs on the local marine environment and to assess their commercial productivity. The acoustic method is the most practical way to determine the distribution and behavior patterns of various fish, which inhabit the three dimensional space. This information is essential to assess the relationship between the artificial reefs and fish behavior and distribution, and furthermore, the seaweed forest. 　　As the area and depth of fishing developed grounds expand, a method for the evaluation of these grounds despite the time and location is a key requirement. To settle this problem, we explored the combined use of acoustic information from sonar and GIS-based 3D visualized software. This study provides a greater understanding of fish schools and seaweed distributions within the marine environment. It is considered that this method provides valuable fundamental information for building effective coastal fishing grounds and reefs.

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To perform the forced roll test using a model ship, it is necessary to accurately estimate the resonance frequency of the roll. If the restoring term of the equation of motion is linear, the frequency response function is a monovalent function. However, assuming that the restoring term is nonlinear, so that it becomes more realistic, the frequency response function becomes a multivalued function. In this study, this problem was overcome using a complete elliptic integral of the first kind.

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The conservation and increase of spawning ground of low-biomass pacific herring Clupea pallasii in Japan is essential for the resource management. The appearance and development of herring egg on installed artificial seaweed and fishing nets in natural habitats were observed. Among two years, no spawning and egg was found on the artificial seaweed in natural habitats. On the other hand, four times spawning and more than 1,000,000 eggs was observed on the artificial seaweed and fishing net in the set net in a year. Almost 100% of egg on the artificial seaweed was fertilized and hatched, however approximately 20% of egg sampled from fishing net was dead due to the egg density at the developing and the external stimuli at the sampling. Therefore, it is probably efficient to focus on the spawn in set net for the conservation and increase of spawning ground of pacific herring by artificial seaweed. In addition to the installation of artificial seaweed in set net, the development of substitutable part in the set net may be more effective.

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We developed a system “Uminavi@Aomori” for browsing automatically acquired sea observation information in Aomori. This system provides various information such as the latest observation value and predicted water temperature in real time on the web site. It contributes to reducing the mortality cultured scallops. The conventional system “Buoy Robot” is operating stably as a business, but it is difficult to customize it according to fishermen's needs. On the other hand, “Uminavi@Aomori” is an inhouse development system, so it can respond flexibly to needs.

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　Recent UAV （Unmanned Aerial Vehicle） is inexpensive and rapidly developed from the ease of maneuvering, and various models ranging from hobby to business use are spreading. UAV is a new technology that enables detailed investigation in places where people are difficult to approach easily and where quantitative localization is necessary. In the event of an emergency, it is also possible to grasp the situation of the site promptly. UAV has become increasingly used in many different fields, and remarkable research and development is in progress. In this paper, we introduced the following method using UAV. 1） Survey of soundness of aged fishing port structures, 2） coastline shoreline surveying, 3） coastal topography and depth survey by laser survey, 4） seaweed bed and coral reef distribution survey, 5） fishing port / fishing ground Security and surveillance. And the challenges and direction of these uses were shown.

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The inspection and diagnosis of the lower part of the pier is the concerning problem due to the poor working environment and labor shortage. In order to address this problem, we have developed the inspection and diagnosis by using wireless LAN boat. The camera attached with wireless LAN boat captures image and these images are studied by various images processing method for the inspection and diagnosis. In addition, we have developed a method that automatically determines the degree of degradation from the captured images. These results have been applied to the 45-year-old pier and compared with the expert judgment. In this paper, the usefulness of the inspection efficiency and the degradation judgment from the proposed development method has been discussed.

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The foundation mound of the offshore deployed structure and artificial seabed mountain ranges for the purpose of restoring fishery resources are created at depths of deep water. This technology is a construction control system aimed at creating riprap mounds at high depth with high precision by direct introduction of riprap. The feature of this system is that by using the individual element method for predicting the shape of deposited sediments, planning and management of riprap entry can be performed in conjunction with site conditions even in a situation where experience is insufficient.

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Until recently, artificial fish reef survey has been evaluated as swarm effect by fish finder, observation of diving, and sampling by various fishing methods, but it was difficult to directly count and analyze the fish school populations. Also, as most of the fishing ports have been developed during the period of high economic growth, aging has progressed and there are enormous number of facilities requiring prompt inspection and maintenance.　　A technology was developed to measure the population size and size of fish school by visualizing underwater using underwater 3D scanner which is compact with high frequency acoustic equipment. Furthermore, a method was developed utilizing multibeam sonar and underwater 3D scanner etc to efficiently measure underwater infrastructure such as fishing port quays and breakwaters in three dimensions, integrating with 3D land data measured by 3D laser to seamless 3D model.

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In Japan, investment of social capital facilities has increased since the 1950s. More than 50 years after, aging these facilities became a social issue, so facility improvement has been in progress. However, as depopulation goes on, tax revenue of local governments also decreases, and lack of investment and human resousces for facility maintenance is concerned. By unifying the electronic format of fishing port records, the costs for developing and using a new database can be increased. Also, by integrating a cloud system to save and use these databases, it will prevent data loss from natural disasters, and reduce labor and costs. Therefore, a cloud ststem for Fisherie Infrastructure Information has been developed and used.

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Amid increasing global demand for marine products and expanding exports, it is required to take measures to eradicate the Illegal, Unreported and Unregulated （IUU） Fishing. More consumers prefer and choose traceable and sustainable products due to growing interest in environment. In Japan, rapidly declining and aging population have a great impact on maintaining fishing communities such as a serious shortage of workers. Therefore, the authors have surveyed major fishing ports and their markets in Europe as well as collected existing reports and information on fishing ports overseas and conducted comparative analysis on the management and operations of the fish market which utilizing ICTs. After clarifying the characteristics of the management and operations overseas and at home, and the background of advanced auction system such as electronic auction and online in Europe, the authors have found that digitalization and expanding network - utilizing ICT such as PCs, tablets, smartphones and the internet - surely contribute to ensuring traceability against IUU Fishing. It is clear that Japan is left far behind in introducing electronic auction apart from the difference of landing, selling and shipping style. The authors have also proposed the digitalized and networked system for the management and operations of the fish market based on the database sales information combined with catch information, designed to realize hygiene highly-managed fishing port - fish market in Japan - which can supply quality, traceable and sustainable marine products to consumers globally. In addition, the proposed system can help market officials, producers and buyers save their labor and time.

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