Feeding ecology of a mysid species, neomysis awatschensis in the lake kasumigaura: Combining approach with microscopy, stable isotope analysis and dna metabarcoding

Yasuhide Nakamura, Akihiro Tuji, Wataru Makino, Shin Ichiro S. Matsuzaki, Nobuaki Nagata, Megumi Nakagawa, Noriko Takamura

Research output: Contribution to journalArticlepeer-review

Abstract

Neomysis awatschensis is an important prey item for various fishes in Lake Kasumigaura, Japan. There is, however, a contradiction concerning the major food sources of this mysid species: whether “bottom mud”, “particulate organic matter (POM) including phytoplankton”, or “mesozooplankton” is the main diet, and this uncertainty may be due to differences in the methodology used to determine the prey items in previous studies. This study examined the main food sources of N. awatschensis by combining three methods to eliminate methodological biases: DNA metabar-coding, microscopy and stable isotope analysis. Planktonic diatoms and green algae sequences were the main taxa detected by DNA metabarcoding and microscopy on the fecal pellets. The δ15N values of the mysids were similar to those of phytoplankton feeders rather than carnivorous planktonic crustaceans. These results suggest that diatoms and green algae were the major food sources for N. awatschensis in Lake Kasumigaura during the investigation period, and that its trophic level is as low as that of herbivores. However, the partial contribution of other “POM” (e.g., benthic diatoms) is also implied, considering the dispersion in δ13C values. Mesozooplankton prey, such as copepods, were detected both using DNA metabarcoding and microscopy, but they could not be a major food source due to the low nitrogen stable isotopic signature of the mysids. The opportunistic feeding habits of N. awatschensis possibly explain the consistent dominance of this species in the lake, where the ecosystem structure was substantially changed because of successive desalination.

Original languageEnglish
Pages (from-to)44-54
Number of pages11
JournalPlankton and Benthos Research
Volume15
Issue number1
DOIs
Publication statusPublished - 2020

Keywords

  • Desalination
  • Fecal pellets
  • Mysida
  • Mysidacea
  • Zooplankton

ASJC Scopus subject areas

  • Oceanography
  • Ecology, Evolution, Behavior and Systematics
  • Aquatic Science
  • Ecology

Fingerprint Dive into the research topics of 'Feeding ecology of a mysid species, neomysis awatschensis in the lake kasumigaura: Combining approach with microscopy, stable isotope analysis and dna metabarcoding'. Together they form a unique fingerprint.

Cite this