Distribution of Japanese Eel Anguilla japonica Revealed by Environmental DNA

The abundance of Japanese eel Anguilla japonica has rapidly decreased in recent decades. Following a re-evaluation of the possibility of extinction, the Japanese Ministry of the Environment and the International Union for Conservation of Nature listed the Japanese eel as an endangered species in 2013 and 2014, respectively. However, their abundance and precise distribution have never been clarified owing to their nocturnality and difficulty in their capture. In this study, the distribution of Japanese eels was investigated by monitoring for environmental DNA (eDNA), a non-invasive and efficient detection method. A total of 365 water samples were collected from 265 rivers located throughout Japan. High concentrations of eDNA of Japanese eels were detected in rivers on the Pacific side, but were low in the Sea of Japan side. In particular, very little eDNA amplification was confirmed from Hokkaido and the north of the Sea of Japan. The eDNA distribution in Japanese rivers coincides with the transport of the larvae in the ocean, as estimated by numerical simulations. Generalized linear mixed models were developed to explain the distribution of eDNA concentrations. The total nitrogen concentration emerged as an important factor in the best model. These results indicate that the distribution of Japanese eel is mostly determined by the maritime larval transport, and their survival and growth depend on the abundance of food in the river. The findings of the present study are useful for the management of populations and in the conservation of Japanese eels.

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Effect of El Niño on migration and larval transport of the Japanese eel (Anguilla japonica)

ICES Journal of Marine Science ◽

10.1093/icesjms/fsm091 ◽

2007 ◽

Vol 64 (7) ◽

pp. 1387-1395 ◽

Cited By ~ 62

Author(s):

Heeyong Kim ◽

Shingo Kimura ◽

Akira Shinoda ◽

Takashi Kitagawa ◽

Yoshikazu Sasai ◽

...

Keyword(s):

El Niño ◽

Western North Pacific ◽

El Nino ◽

Anguilla Japonica ◽

Japanese Eel ◽

Larval Transport ◽

North Equatorial Current ◽

The North ◽

Equatorial Current ◽

The Kuroshio

Abstract Kim, H., Kimura, S., Shinoda, A., Kitagawa, T., Sasai, Y., and Sasaki, H. 2007. Effect of El Niño on migration and larval transport of the Japanese eel (Anguilla japonica). – ICES Journal of Marine Science, 64: –. To clarify the effect of an El Niño on the migration of Japanese eels (Anguilla japonica) in the western North Pacific, differences in migration patterns of eel larvae (leptocephali) in El Niño and non-El Niño years were compared qualitatively through a numerical particle-tracking model. Depending on interannual meridional displacements of the salinity front and bifurcation of the North Equatorial Current, transport of Japanese eel larvae to the Kuroshio was much less than to the Mindanao Current in an El Niño year, and recruitment to coastal habitats in Japan decreased in those years. In non-El Niño years, transport to the Kuroshio was twice as high, and recruitment to coastal habitats increased. If the spawning area of eels was independent of El Niño, transport differences between the two currents were not clear. In the western North Pacific, mesoscale eddies also played a significant role in dispersing eel larvae and prolonging their migration. Consequently, the changing oceanic conditions associated with climate change have resulted in decreased recruitment of Japanese eels, and the eddy effect on migration of the Japanese eel larvae needs to be added into the North Equatorial Current–Kuroshio system.

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Assessment of ecological state of the Posyet Bay (the Sea of Japan) by heavy metals content in brown algae

Samara Journal of Science ◽

10.17816/snv201762118 ◽

2017 ◽

Vol 6 (2) ◽

pp. 91-95

Author(s):

Nadezhda Konstantinovna Khristoforova ◽

Anna Dmitrievna Kobzar

Keyword(s):

Heavy Metals ◽

Sea Of Japan ◽

Coastal Waters ◽

Atmospheric Transport ◽

The Sea Of Japan ◽

High Concentration ◽

The North ◽

Recreational Pressure ◽

North Western ◽

Sargassum Miyabei

The paper contains the study of heavy metals in three species - Sargassum miyabei , Sargassum pallidum , Cystoseira crassipes in the coastal waters of the Posyet Bay. The analysis of the spatial distribution of trace elements revealed the highest contents of zinc, copper and nickel in the Troitsa Bight, due to recreational pressure and a high concentration of nickel and cadmium in Sivuchya Bight that was caused by transboundary atmospheric transport. All of detected concentrations exceed natural background values for the North-Western part of the Sea of Japan. The authors show that there has been a distinct change in the environmental situation in the the Posyet Bay since 1998: the concentration of lead has sharply decreased, the content of zinc, copper and cadmium has decreased, it could be connected with influence reduction in the free economic zone, located on the Chinese side on the Tumannaya River.

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Deep-sea mysids (Crustacea: Mysida) in the north part of the Sea of Japan with description of new species from genus Meterythrops

Russian Journal of Marine Biology ◽

10.1134/s106307401502008x ◽

2015 ◽

Vol 41 (2) ◽

pp. 94-102

Author(s):

V. V. Petryashov

Keyword(s):

New Species ◽

Sea Of Japan ◽

Deep Sea ◽

The Sea Of Japan ◽

The North ◽

North Part

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The barnacleBalanus rostratusand its habitats in the north-western part of the Sea of Japan

Ophelia ◽

10.1080/00785326.1998.10409372 ◽

1998 ◽

Vol 49 (1) ◽

pp. 47-54 ◽

Cited By ~ 7

Author(s):

Alla V. Silina ◽

Ida I. Ovsyannikova

Keyword(s):

Sea Of Japan ◽

The Sea Of Japan ◽

The North ◽

North Western

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Distribution and some traits of biology of the elongated sculpin Alcichthys elongatus in the north-western part of the Sea of Japan

Journal of Ichthyology ◽

10.1134/s0032945211010103 ◽

2011 ◽

Vol 51 (3) ◽

pp. 217-226 ◽

Cited By ~ 4

Author(s):

V. V. Panchenko ◽

O. I. Pushchina ◽

D. V. Antonenko ◽

S. F. Solomatov ◽

P. V. Kalchugin

Keyword(s):

Sea Of Japan ◽

The Sea Of Japan ◽

The North ◽

North Western

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RESEARCHES OF THE RED SNOW CRAB CHIONOECETES JAPONICUS (DECAPODA, MAJIDAE) IN THE SEA OF JAPAN. 5. FUNCTIONAL STRUCTURE OF THE POPULATION FROM THE NORTH-EAST PART OF THE SEA OF JAPAN

Problems of fisheries ◽

10.36038/0234-2774-2016-17-3-277-289 ◽

2016 ◽

Vol 17 (3) ◽

pp. 277-289

Author(s):

A.I. Buyanovsky ◽

◽

V.V. Miroshnikov ◽

Keyword(s):

Sea Of Japan ◽

Functional Structure ◽

Snow Crab ◽

The Sea Of Japan ◽

East Part ◽

North East ◽

The North ◽

Red Snow Crab

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Morphology of larvae of the family Mytilidae (Bivalvia) from the north-western part of the Sea of Japan

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315408000659 ◽

2008 ◽

Vol 88 (2) ◽

pp. 331-339 ◽

Cited By ~ 9

Author(s):

Olga Ya. Semenikhina ◽

Natalya K. Kolotukhina ◽

George A. Evseev

Keyword(s):

Sea Of Japan ◽

Morphological Characters ◽

Shell Morphology ◽

Larval Shell ◽

The Sea Of Japan ◽

Time Interval ◽

Musculista Senhousia ◽

The North ◽

The Family ◽

Modiolus Kurilensis

The larval shell morphology of 10 bivalve species of the family Mytilidae (Adula falcatoides, Crenella decussata, Crenomytilus grayanus, Modiolus kurilensis, Musculista senhousia, Mytilus coruscus, Mytilus galloprovincialis, Mytilus trossulus and Septifer keenae, and an unidentified species Mytilidae indeterminate) from the Sea of Japan is described. The following morphological features were comparatively examined: larval shell outlines including shape and size of umbones, and anterior, posterior and ventral margins, hinge morphology, ligament location, sculpture, colour, and eye-spot outlines. Some dimensional parameters of larval shells are given. The time interval of occurrence of larvae in the plankton, water temperature in this period, and shell length of competent larvae are presented. It is demonstrated that, in spite of sometimes similar external morphological characters, identification of mytilid larvae creates no difficulties if all distinguishing characters are used.

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Diversity of corticolous myxomycetes in the last glacial refugia of Cryptomeria japonica in Japan

Karstenia ◽

10.29203/ka.2020.499 ◽

2020 ◽

pp. 260-274

Author(s):

Kazunari Takahashi

Keyword(s):

Species Diversity ◽

Sea Of Japan ◽

Cryptomeria Japonica ◽

Host Tree ◽

Ice Age ◽

The Sea Of Japan ◽

Fruiting Bodies ◽

Yakushima Island ◽

Biogeographical Distribution ◽

Pacific Side

Cryptomeria japonica, commonly known as Japanese cedar, is now widely distributed from glacial refuges to the entire Japanese archipelago, after the last ice age. The bark surface provides a habitat for many corticolous myxomycetes. Although corticolous myxomycetes are known to prefer tree species, the association between myxomycete distribution and host tree (C. japonica) divergence across the refuges has not been investigated. In this study, myxomycete communities in five refuges were assessed and compared with those in 14 peripheral areas. Bark samples were collected from at least 10 trees per site and were subjected to the moist chamber culture method (10 Petri dishes per tree) to examine the myxomycete fruiting bodies strictly. Environmental variables such as geographical location, climate condition, and bark traits (tree size, bark pH, and electric conductivity) were measured. Fruiting bodies appeared in 91% of the cultures, and 32 taxa (31 species and one varie ty) were recorded. Comparison of the communities between refuges and peripheral sites showed six myxomycete species, Arcyria cinerea, Macbrideola argentea, Cribraria minutissima, Clastoderma debaryanum, Physarum viride and Physarum pusillum, were significantly more abundant in the refuges and these communities preserved higher species diversity. By nonmetric multidimensional scaling, the communities in the Pacific side and the Sea of Japan side were ordered based on snow cover depth, in a pattern similar to the phylogenetic distribution of the host tree. Myxomycete groups were identified in the northern region, the Sea of Japan region, and the southern region (including Yakushima Island) of Japan. Thus, the refugial tree populations preserved the myxomycete species diversity on their bark and functioned as an important hotspot for myxomycetes. The distribution of corticolous myxomycetes was associated with the diversification and biogeographical distribution history of their host tree, C. japonica.

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