EVALUATE OF FISH GATHERING ON COASTAL SUBSTRATUMS USING ENVIRONMENTAL RNA AND DNA

Abstract

 The purpose of this study is to evaluate the fish gathering on seaweed beds, fish reef seagrass bed and sediment area using environmental RNA/DNA in Hiroshima Bay by comparing with monitoring data by stationary cameras. In the artificial seaweed beds, fish reef blocks, seagrass bed, and surrounding sediment area in Shinto, Iwakuni City, Yamaguchi Prefecture, the average population of Sebastes inermis was higher than other fish species, however it was about one-tenth compared to September 2018 to December 2021. There was a positive correlation between DNA copy number and possibility of appearance of Sebastes inermis in artificial seaweed beds and sediment areas. However no correlation with RNA copy number could be confirmed. When fish were not detected, RNA was more often undetected than DNA, and environmental RNA was more accurate. The possibility of appearance of fish was low, it was not possible to quantitatively evaluate fish gathering in the oscillatory flow using environmental DNA and/or RNA in the oscillatory flow.