The first research meeting of the Ministry of Land, Infrastructure, Transport and Tourism's Chikuma River and Shinano River Research Project in fiscal year 2024 has been held!

On Friday, May 17, 2024, the first research meeting of the research group (research leader: Professor Hiroshi Hakoyama) of the Ministry of Land, Infrastructure, Transport and Tourism’s River Erosion Control Technology Research and Development and River Ecology General Research “The Importance of Habitat Continuity in Rivers - Research on Impact Assessment and Conservation Measures for River Ecosystems” was held. We had a first discussion about this year’s research (survey overview, schedule for presentation of results, etc.) and the on-site inspection meeting of the River Academic Ecology Research Group scheduled for October 17-18. This time, not only researchers from Nagano University Institute of Freshwater Biology, Nagano Prefectural Fisheries Experiment Station, and Shinshu University Faculty of Engineering, but also from Chikuma River Office, Shinano River Office, and Riverfront Research Institute attended, and there was a lively discussion about the research outline and plans for this year.

The research will be conducted in the Chikuma River system and aims to clarify the effects of disturbances in the river ecosystem and the presence of river works on the continuity of habitats and the health and sustainability of populations and communities.

Freshwater fish use different habitats by dispersing and migrating. Habitat fragmentation and flooding disturbances that impede such habitat use affect the movement and distribution of fish and the survival of populations. In fact, there are concerns about a significant decline in fish populations in the Chikuma River and Shinano River, and it is believed that a significant cause is habitat fragmentation. Therefore, we will investigate the continuity of river habitats and the quality of each habitat, evaluate the impact of river structures and flood disturbances that impede fish movement on fish declines, and propose plans to restore fish habitat use throughout the river system by improving fish passages, etc.