We participated in the Chiba Prefecture Glass Eel Survey at the Tone River Estuary Barrage!

On Saturday, February 10, 2024, Professor Hiroshi Hakoyama and Research Assistant Chiaki Okamoto of the Institute of Freshwater Biology participated in a glass eel migration survey conducted by the Chiba Prefectural Inland Fisheries Research Institute at the Tone River Estuary Barrage. The survey uses a bag net to determine the number of glass eels migrating up the river. There is a lot of bycatch, including Japanese mullet, ice fish, red mullet and blue crab, as well as non-native fish such as silver carp and Pacific thrush, so it is necessary to sort the glass eels to find them.

This survey is part of a research project by the Eel Unit (Unit Leader: Hiroshi Hakoyama), a research project commissioned by the Fisheries Agency, and is being conducted to understand the migratory status of glass eels in the Tone River over time and to use the information for resource management (the Eel Unit is currently conducting migratory volume surveys in a total of five regions: Chiba, Wakayama, Fukuoka, Miyazaki and Kagoshima prefectures).