We conducted a survey on the spawning migration of wild eels in Shizuoka and Kumamoto!
IFB
We conducted a spawning migration survey using pop-up tags on natural downstream eels in Shizuoka Prefecture on December 2, 2024, and in Kumamoto Prefecture on December 13, 2024.
In Shizuoka Prefecture, we set out by boat from Lake Hamana and released five individuals in an area approximately 700 meters deep.
In the Ariake Sea in Kumamoto Prefecture, we released three individuals in shallow water inside the bay.
This is the first time we have tried to collect data on eels migrating to the open ocean. We saw many dolphins from the boat!
We received cooperation from Ebisen Co., Ltd., the Fishing Shop BLUEJUNKIE, and the Kumamoto Prefectural Fisheries Research Center for this survey.
Thank you very much.
Nagano University Mitsuo Seminar Students Visited the Freshwater Biology Research Institute!
IFB
On Thursday, December 12, 2024, 15 first-year seminar students of Professor Yoshito Mitsuo visited the Freshwater Biology Research Institute as part of their seminar activities. The seminar students were given an explanation about the Freshwater Biology Research Institute, research projects on river ecology and Japanese eel, and the research, education, social contributions, and history of the Freshwater Biology Research Institute faculty. They also toured the wild fish stocks on the premises, as well as the facilities and equipment.
The Chikuma-Shinano Rivers Research Group presented their results at the River Ecology Academic Research Presentation (Tokyo Shoken Hall)
IFB
On November 21, 2024, the Chikuma River and Shinano River Research Group presented their results at the River Ecology Academic Research Presentation at the Tokyo Shoken Hall.
Hiroshi Hakoyama* (IFB, Nagano University) On the importance of habitat continuity for riverine ecosystems and related restoration measures.
Alessandra CERA*, Sakie KODAMA, Leanne FAULKS, Hiroshi HAKOYAMA (IFB, Nagano University) Effects of water flow velocity on metabolic functionality of freshwater epilithic biofilms: a field and laboratory study.
Leanne FAULKS*, Alessandra CERA, Sakie KODAMA, Hiroshi HAKOYAMA (IFB, Nagano University) River fragmentation at the local scale: effects on biodiversity.
Takato IDO, Mei YOSHIMURA, *Masashi TOYOTA (Faculty of Engineering, Shinshu University) River channel evolution in the middle reaches of the Chikuma River as seen from cross-sectional survey data and aerial photographs
Professor Hakoyama's Comments Published in Nihon Keizai Shimbun Article
IFB
On November 20, 2024, Professor Hiroshi Hakoyama’s comments were published in the Nihon Keizai Shimbun print and online articles “Minister of Land, Infrastructure, Transport and Tourism encourages setting numerical targets for river environment conservation, such as tidal flat area, visualization of ecosystem recovery” and “Ministry of Land, Infrastructure, Transport and Tourism sets new targets for river environment and ecosystem maintenance”.
The 8th IFB Seminar took place in the conference room of the Institute of Freshwater Biology.
Title: Fish that adapt their buoyancy to the environment
Lecturer: Yoshida Makoto
Affiliation: Special Researcher, Atmosphere and Ocean Research Institute, University of Tokyo
Abstract: Many fishes that swim underwater support their weight by obtaining buoyancy from the air in their swim bladders, reducing energy expenditure during swimming. On the other hand, in situations where sufficient buoyancy is not available, they use gliding swimming, which involves diving without swinging the caudal fin, to reduce the cost of locomotion. I will report on biological research on freshwater catfish and two strains of carp from Lake Biwa, taking into account the quality associated with maintaining buoyancy. I inferred the buoyancy state of Carrera during swimming from the behavioral records of the fish in the wild. Through these studies focusing on the trends in buoyancy regulation according to habitat, we will consider the behavioral adaptation of the three fish species from the perspective of buoyancy.
On October 24, 2024, a meeting of the Glass Eel Research Group of the International Resource Project Eel Unit, commissioned by the Fisheries Agency, was held at the Institute of Freshwater Biology. The Glass Eel Research Group is conducting long-term studies of glass eel migration in several regions through direct, non-fishing surveys. The meeting was also streamed online and was attended by more than 20 people from the Fisheries Agency and the Eel Unit. Lively discussions followed the agenda below.
Meeting Agenda
Date: October 24th
Time: 13:30-15:40
Location: Institute of Freshwater Biology Conference Room, 1088 Komaki, Ueda City, TEL 0268-22-0594
Opening Ceremony
Survey of glass eels in Miyazaki, Teru Takahashi/Shuichi Hayashida (online) (13:30-13:50)
Glass eel survey in Wakayama, Yoshitsugu Kaji (13:50-14:10)
Glass eel survey in Kagoshima, Takashi Shiosaki (14:10-14:30)
10 minute break (14:30-14:40)
Glass eel survey in Fukuoka, Noritaka Mochioka (14:40-15:00)
Glass eel survey in Chiba, Yasuhiko Mabuchi (15:00-15:20)
General discussion (15:20-15:40)
Conclusion
10-minute break (15:40-15:50)
Data Analysis Session
Time: 15:50-18:00
Time series data analysis 2 by Hakoyama Hiroshi (15:50-16:10)
Discussion of Analysis of Survey Data from Each JV (16:10-18:00, with breaks)
The 2024 River Ecology Academic Research Group Chikuma River Field Trip was held!
IFB
A field trip to the research area of the Chikuma River and Shinano River Research Group (represented by Professor Hiroshi Hakoyama), which is part of the River Ecology Academic Research Group, was held on October 17 and 18. More than 50 people participated in the research, including members of the parent committee of the River Ecology Academic Research Group, members of the research group and related departments of the Ministry of Land, Infrastructure, Transport and Tourism, and the Riverfront Research Institute as the secretariat. This project research, funded by the River Ecology Research Fund of the Ministry of Land, Infrastructure, Transport and Tourism, focuses on the effects of river fragmentation on fish populations and communities. We are studying the fragmentation of the Shinano River by large dams and other structures throughout the river, and the fragmentation of the main river, tributaries, and irrigation canals by relatively small weirs. During this tour, we compared the Miyanaka Water Intake Dam and the small weirs at the Institute of Freshwater Biology, and also visited construction sites (Kamiimai Reservoir, etc.) for river basin flood control projects being implemented by the Chikuma River Office (photo). The primary goal of the Chikuma River and Shinano River Research Group is academic research, and the results will be useful for the river basin flood control projects conducted by the Ministry of Land, Infrastructure, Transport and Tourism.
7th UNMP Hosted by Ueda Nishi High School Students Held at Institute of Freshwater Biology!
IFB
The 7th UNMP (Ueda Nishi Learning Project) was held on the morning of September 23, 2024 in the conference room of the Institute of Freshwater Biology. Five students participated and gave presentations on their respective topics of interest: the relationship between water quality environment and living organisms of the Chikuma River, the ecology of aquatic insects, and the ecology of the Japanese newt. In addition, the Institute of Freshwater Biology presented the ecology of lampreys and water quality analysis of the Chikuma River. The Ueda Nishi High School Biology Club and the Institute of Freshwater Biology regularly hold events and cooperate in research activities.
Associate Professor Kodama Attends River Environment Conservation Monitor Conference Hosted by the Ministry of Land, Infrastructure, Transport and Tourism
IFB
On September 10, 2024, Associate Professor Kodama of the Institute of Freshwater Biology participated in the River Environment Conservation Monitor Conference for the Chikuma River Office of the Ministry of Land, Infrastructure, Transport and Tourism regarding construction projects that will affect the river channel as the person in charge of fish. She visited the proposed sites for flood control basins, river channel excavation, and public tree cutting in the Chikuma River basin, and gave her opinion on the project plan from the perspective of river environment conservation for fish. This project was established as an emergency flood control measure in response to the East Japan Typhoon that caused severe damage in 2019, and is being implemented with reference to the ecological perspective of fish, birds, and plants. With the aim of achieving both flood control and nature restoration, river project plans are being implemented that also aim to provide a multi-nature environment and environmental education.
