title: Environmental DNA as a 'Snapshot' of Fish Distribution: A Case Study of Japanese Jack Mackerel in Maizuru Bay, Sea of Japan.
abstract: Recent studies in streams and ponds have demonstrated that the distribution and biomass of aquatic organisms can be estimated by detection and quantification of environmental DNA (eDNA). In more open systems such as seas, it is not evident whether eDNA can represent the distribution and biomass of aquatic organisms because various environmental factors (e.g., water flow) are expected to affect eDNA distribution and concentration. To test the relationships between the distribution of fish and eDNA, we conducted a grid survey in Maizuru Bay, Sea of Japan, and sampled surface and bottom waters while monitoring biomass of the Japanese jack mackerel (Trachurus japonicus) using echo sounder technology. A linear model showed a high R(2) value (0.665) without outlier data points, and the association between estimated eDNA concentrations from the surface water samples and echo intensity was significantly positive, suggesting that the estimated spatial variation in eDNA concentration can reflect the local biomass of the jack mackerel. We also found that a best-fit model included echo intensity obtained within 10-150 m from water sampling sites, indicating that the estimated eDNA concentration most likely reflects fish biomass within 150 m in the bay. Although eDNA from a wholesale fish market partially affected eDNA concentration, we conclude that eDNA generally provides a 'snapshot' of fish distribution and biomass in a large area. Further studies in which dynamics of eDNA under field conditions (e.g., patterns of release, degradation, and diffusion of eDNA) are taken into account will provide a better estimate of fish distribution and biomass based on eDNA.
authors.affiliation: Graduate School of Human Development and Environment, Kobe University, Hyogo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Faculty of Fisheries Sciences, Hokkaido University, Hokkaido, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Minami
authors.affiliation: The Institute of Statistical Mathematics, Tokyo, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Fukaya
authors.affiliation: Maizuru Fisheries Research Station, Kyoto University, Kyoto, Japan.
authors.forename: Kohji
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Maizuru Fisheries Research Station, Kyoto University, Kyoto, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Sawada
authors.affiliation: Maizuru Fisheries Research Station, Kyoto University, Kyoto, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Murakami
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Satsuki
authors.initials: S
authors.lastname: Tsuji
authors.affiliation: Graduate School of Human Development and Environment, Kobe University, Hyogo, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Hashizume
authors.affiliation: Graduate School of Environmental Science, Hokkaido University, Hokkaido, Japan.
authors.forename: Shou
authors.initials: S
authors.lastname: Kubonaga
authors.affiliation: Maizuru Fisheries Research Station, Kyoto University, Kyoto, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Horiuchi
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Hongo
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Jo
authors.initials: J
authors.lastname: Nishida
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Okugawa
authors.affiliation: Faculty of Human Development, Kobe University, Hyogo, Japan.
authors.forename: Ayaka
authors.initials: A
authors.lastname: Fujiwara
authors.affiliation: Faculty of Human Development, Kobe University, Hyogo, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Fukuda
authors.affiliation: Faculty of Human Development, Kobe University, Hyogo, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Hidaka
authors.affiliation: Maizuru Fisheries Research Station, Kyoto University, Kyoto, Japan.
authors.forename: Keita W
authors.initials: KW
authors.lastname: Suzuki
authors.affiliation: Natural History Museum & Institute, Chiba, Chiba, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Miya
authors.affiliation: Research Faculty of Agriculture, Hokkaido University, Hokkaido, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Araki
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamanaka
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Maruyama
authors.affiliation: Field Science Center for the Northern Biosphere, Hokkaido University, Hokkaido, Japan.
authors.forename: Kazushi
authors.initials: K
authors.lastname: Miyashita
authors.affiliation: Maizuru Fisheries Research Station, Kyoto University, Kyoto, Japan.
authors.forename: Reiji
authors.initials: R
authors.lastname: Masuda
authors.affiliation: Graduate School of Human Development and Environment, Kobe University, Hyogo, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Minamoto
authors.affiliation: Department of Environmental Solution Technology, Faculty of Science and Technology, Ryukoku University, Shiga, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Kondoh
mesh_terms: D000818:Animals; D061006:Bays; D018533:Biomass; D004247:DNA / Q000235:genetics*; D017753:Ecosystem; D007564:Japan; D010473:Perciformes / Q000235:genetics*
chemical_list: D004247:DNA