PLoS ONE (Jan 2016)

Environmental DNA as a 'Snapshot' of Fish Distribution: A Case Study of Japanese Jack Mackerel in Maizuru Bay, Sea of Japan.

  • Satoshi Yamamoto,
  • Kenji Minami,
  • Keiichi Fukaya,
  • Kohji Takahashi,
  • Hideki Sawada,
  • Hiroaki Murakami,
  • Satsuki Tsuji,
  • Hiroki Hashizume,
  • Shou Kubonaga,
  • Tomoya Horiuchi,
  • Masamichi Hongo,
  • Jo Nishida,
  • Yuta Okugawa,
  • Ayaka Fujiwara,
  • Miho Fukuda,
  • Shunsuke Hidaka,
  • Keita W Suzuki,
  • Masaki Miya,
  • Hitoshi Araki,
  • Hiroki Yamanaka,
  • Atsushi Maruyama,
  • Kazushi Miyashita,
  • Reiji Masuda,
  • Toshifumi Minamoto,
  • Michio Kondoh

DOI
https://doi.org/10.1371/journal.pone.0149786
Journal volume & issue
Vol. 11, no. 3
p. e0149786

Abstract

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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.