Grazing by the mysid Neomysis mirabilis during the warm season in a coastal lagoon in northeastern Japan

Yoshizumi Nakagawa; Fumiko Hirasawa; Koji Asakuma.

Mysids of the genus Neomysis are omnivorous, feeding on microalgae, zooplankton, and detritus, and are preyed upon by fish. Neomysis mirabilis is the most dominant mysid in the subarctic Notoro Lagoon, located on the coast of northeastern Hokkaido, Japan. The feeding habit of N. mirabilis was demonstrated as herbivorous during the icy season but has not yet been determined for the longer duration of the warm season. In this study, N. mirabilis were collected from the surface water of Notoro Lagoon in August to October 2023. To determine grazing by N. mirabilis on microalgae during the warm season we estimated the daily ration using gut pigment contents and the gut passage time in a gut evacuation experiment and then compared the data with the estimated carbon requirement. The average daily ration (carbon derived from the consumption of microalgae) ranged from 43.7 to 89.3 μg C ind.^-1 day^-1 from August to October. The percent composition of the daily ration of microalgae to the metabolic requirement of N. mirabilis ranged from 24.7% to 54.7%. These results reveal that the feeding habit of N. mirabilis can be omnivorous during the warm season.

KEYWORDS: Neomysis mirabilis; Feeding habit; Gut pigment; Daily ration; Notoro Lagoon



Download this PDF file

REFERENCES

1. Chiba, S. & Kawamura, T. 2011. Ecosystem services supplied by invertebrate resources. In: Shoji, J., Hori, M. & Yamashita, Y. (Eds.). Ecosystem Services of Coastal Waters―Benefits of the Sea and its Sustainable Use. Tokyo: Kouseisha-Kouseikaku (In Japanese).
2. Dagg, M. J. & Wyman, K. D. 1983. Natural ingestion rates of Neocalanus plumchrus and N. cristatus calculated from gut contents. Marine Ecology Progress Series, 13, 37-46.
3. De Jonge, V. N. 1980. Fluctuations in the organic carbon to chlorophyll a ratios for estuarine benthic diatom populations. Marine Ecology Progress Series, 2, 345-353.
4. Gnaiger, E. 1983. Calculation of energetic and biochemical equivalents of respiratory oxygen consumption. In: Gniger, E. & Forstner, H. (Eds). Polarographic oxygen sensors. New York: Springer.
5. Holm-Hansen, O., Lorenzen, C. J., Holmes, R. W., & Strickland, J. D. H. 1965. Fluorometric determination of chlorophyll. Journal du conseil - Conseil international pour l'exploration de la mer, 30, 3-15.
6. Ii, N. 1964. Fauna Japonica, Mysidae (Crustacea). Biogeographical Society of Japan. National Science Museum.
7. Ikeda, T. 1974. Nutritional ecology of marine zooplankton. Memoirs of the Faculty of Fisheries Hokkaido University, 22, 1-97.
8. Ikeda, T. 1985. Metabolic rates of epipelagic marine zooplankton as a function of body mass and temperature. Marine Biology, 85, 1-11.
9. Mauchline, J. 1980. The biology of mysids and euphausiids. Advances in Marine Biology, 18: 1-681.
10. Murano, M. 1963. Fisheries biology of a marine relict mysid Neomysis intermedia Czerniawsky II. On the food habits. Suisanzoshoku, 11, 158-165 (In Japanese).
11. Takahashi, K. 2004. Feeding ecology of mysids in freshwater and marine coastal habitats: a review. Bulletin of the Plankton Society of Japan, 51, 46−72 (In Japanese with English abstract).
12. Takahashi, K., Nagao, N. & Taguchi, S. 2015. Diel distribution and feeding habits of Neomysis mirabilis under seasonal sea ice in a subarctic lagoon of northern Japan. Aquatic Biology, 23, 183-190.
13. Yamada, K., Takahashi, K., Vallet, C., Taguchi, S. & Toda, T. 2007. Distribution, life history, and production of three species of Neomysis in Akkeshi-ko estuary, northern Japan. Marine Biology, 150, 905-917.
14. Yamada, K. 2008. Functional responses and effects of macrofaunal community at a seagrass meadow in northeastern Japan. PhD Thesis, Chiba University, Japan.
15. Yusa, T. & Goshima, S. 2011. Life history of Neomysis mirabilis (Crustacea: Mysidacea) in Notoro Lagoon, Hokkaido, Japan. CRUSTACEAN RESEARCH, 40, 81-92.
16. Willason, S. W. & Cox, J. L. 1987. Diel feeding, laminarinase activity, and phytoplankton consumption by euphausiids. Biological Oceanography, 4, 1-24.