We analyze the population size of Japanese eels using a next-generation

Next-generation sequencers (NGS) are state-of-the-art genetic analysis instruments that can decipher genome sequences at high speed. The Institute of Freshwater Biology owns a model called NextSeq 550 from Illumina, and researcher Faulks, research assistant Fujimori, and research assistant Daryani are the main researchers conducting analysis to read a large number of gene sequences of Japanese eels.

As shown in the figure, the number of juvenile Japanese eels (glass eels) has declined significantly, and the IUCN has listed them as an endangered species. Eel farming begins with the introduction of wild glass eels into farm ponds, so it is also necessary to protect glass eel resources for eel farming. To manage and conserve eel resources, it is necessary to understand the status of Japanese eel populations (groups) using various methods, and gene analysis using NGS makes it possible to estimate a certain population size (effective population size).

This research is part of a research project led by the Institute of Freshwater Biology, Nagano University, in collaboration with 35 universities, prefectural fisheries research institutes, and other testing and research institutions nationwide as part of the Fisheries Agency’s Fisheries Resource Survey and Evaluation Promotion Commissioned Project (Commissioned Project).