Northern Japan Sea Research Articles

Linguistic and Cultural Sketches in John M. Tronson´s Travel Diary

The article deals with the linguistic and cultural sketches in the book “A Voyage to Japan, Kamtchatka, Siberia, Tartary and various parts of the coast of China; in H.M.S. Barracouta” (1859) by John M. Tronson. The travel notes of the English author remain almost unknown in Russia. The only exception is the reference to this book by Peter Leopold von Schrenck in “Essay on Physical Geography of the Northern Sea of Japan” (1869). The linguistic and cultural content of the book presents to readers various descriptions of the Chinese, Manchu, Japanese, Korean languages, as well as the language of the Tungusic people (mistakenly taken for the Nivkh (in the book — Gilyak) language by John M. Tronson). At the same time, the interest is attracted by the Peoples of „Japan, Kamtchatka, Siberia, Tartary and China” perception of English as a mean of communication with the representatives of the European civilization. The author´s reference to the words from Japanese, Chinese, Korean and other languages is being perceived as a pioneering stage in creating in the middle of the XIX century European awareness for the culture of the Russian Far East Peoples (chiefly concerned with living environment). Regardless of being episodic, the linguistic and cultural descriptions in John M. Tronson´s travel notes are essential for the similar literature genres. The notes of the English author are regarded as the part of other travel works on Russian Far East, i.e. “Frigate ‘Pallada’” (1853-1857) by Ivan A. Goncharov. The Russian author provides not only personal observations but also scientific information on the emergence and evolution of the other Peoples languages. John M. Tronson introduces the words of foreign sound and origin, and familiarizes his readers with the realities that are absolutely new and unusual for European conscience. By acquainting with “new” world (through the reproduction of what we see, hear and interpret) different educational tasks that are bound to travelling and its genre varieties (travel notes, sketches, essays, adventures and others) are realized.

Nuclear microsatellites reveal population genetic structuring and fine-scale pattern of hybridization in the Japanese mantis shrimp Oratosquilla oratoria.

The interplay between historical and contemporary processes can produce complex patterns of genetic differentiation in the marine realm. Recent mitochondrial and nuclear sequence analyses revealed cryptic speciation in the Japanese mantis shrimp Oratosquilla oratoria. Herein, we applied nuclear microsatellite markers to examine patterns and causes of genetic differentiation in this morphotaxon. Population structure analyses revealed two genetically divergent and geographically structured clades in O. oratoria, one dominating the temperate zone of the Northwestern (NW) Pacific and the other occurring in the subtropical and tropical waters where are influenced by the Kuroshio Current. Two sympatric zones, one around the Changjiang Estuary in China coast and the other in the northern Japan Sea, were demonstrated to be hybrid zones where introgressive hybridization occurred asymmetrically. The interaction between historical climate shifts and contemporary factors (e.g., freshwater discharge, temperature gradient and isolation by distance) may contribute to the present-day genetic architecture in the Japanese mantis shrimp. Range shift induced by climate changes and oceanographic factors may promote hybridization and gene flow between the O. oratoria complex. Our results provide insights into the interacting mechanisms that give rise to diversification and speciation of coastal species in the NW Pacific.

Current state of resources for japanese flying squid Todarodes pacificus in the northwestern Tatar Strait (Japan Sea)

Data on commercial catches of japanese flying squid Todarodes pacificus in the northwestern Tatar Strait in 2003–2019 are analyzed. To assess the resours status in the study area, the relative number (individuals per jigger winch per hour) and biomass (kilograms per vessel per day) marks recognized to be the most applicable winch per hour or the catch in kg per vessel per day. The average CPUE value was 35.6 ± 3.6 ind./winch/hour; increasing trend of CPUE is observed (α = 1.5 ± 0.6, r2 = 0.3, p < 0.03). The squid abundance decreased slightly in the last 2 years, with CPUE decreasing to 28 ind./winch/hour in 2019, though the squid biomass was relatively stable (average CPUE 582.0 ± 45.8 kg/vessel/day) — decreased number of caught individuals was compensated by individual body weight increasing. Long-term tendency to the body weight increasing was noted: the average body weight was 205.0 ± 4.0 g in 2004, 256.0 ± 3.5 g in 2012, and 297.0 ± 6.3 g in 2019. Possible climate change influence on the squid population was discussed. Because of warming in the reproductive area of T. pacificus in the southern Japan Sea, SST in the spawning period reached 20–25 оC and exceeded the value optimal for reproduction and larvae development (15–23 оC), so the squid abundance decreased. On the contrary, in the northern Japan Sea (in the Tatar Strait) the warming caused better conditions for the squid feeding: the higher zooplankton biomass in this area was observed under SST 13–18 оC that is reached every year recently. On the other hand, the Tsushima Current intensifying promoted active migrations of T. pacificus to the northwestern Tatar Strait. These factors of climate warming ensure favorable environments for northward migrations of T. pacificus and forming of dense feeding aggregations in the northwestern Tatar Strait that allows to expect good conditions for the squid fishery in this area in the nearest future.

Hydrocarbon gases in seafloor sediments of the TATAR strait, the northern sea of Japan

The distributions of hydrocarbon gases (HCGs) from C1-C5 in seafloor sediments of the South Tatar sedimentary basin (northern Sea of Japan) were obtained during five research cruises from 2012 to 2017. As a result of this work, areas of gas hydrates, gas flares, and anomalous gas concentrations were discovered. The concentration of HCGs in seafloor sediment, as determined by the “headspace method” varied from 0.38 to 149,000 ppm, with a median of 177 ppm (N = 1420). The median values of HCGs for the Western, Central, and Eastern part of the South Tatar sedimentary basin are 11.7, 99, and 1134 ppm, respectively. Maximum values and gradients in concentrations of HCGs were found in the central and eastern parts of Tatar Strait, where multiple cores contain gas hydrates and gas-saturated sediments. The predominant gas component in all samples was methane, but relatively high concentrations of ethane (up to 789 ppm) and propane (up to 111 ppm) occur. Methane concentrations below 5.25 ppm can be considered as regional background for near seafloor (0–15 cm) sediments from the South Tatar sedimentary basin. The С1/(С2 + С3) ratio across all samples ranges between 2.6 and 345,000, with a median value of 219. The presence of a large-scale degassing zone exists in the northeastern part of Tatar Strait, which coincides with areas of gas hydrates and gas anomalies in the sediments and gas flares in the water column.

A Mesocyclone over the Northern Sea of Japan in February 2013

The article considers a particular event in the influence of a mesoscale cyclone (MC) on the northern Sea of Japan on February 10–11, 2013. The passage of the MC was accompanied by a sharp increase in wind to storm conditions, an almost twofold decrease in total heat transport, and a fourfold increase in the momentum flux. Perturbations of the hydrological characteristics in the wake of the MC estimated from data of two Argo floats were traced to a depth of 300 m off the west coast of Hokkaido and up to ~100 m in the deep-water region, caused by the difference in the background stability of the vertical structures. Several estimates of the contribution of various factors to the observed variability of the upper sea layer are given.

Delineating management units for Pacific cod (Gadus macrocephalus) in the Sea of Japan

Advances in population genetics have brought about the use of management units (MUs) for the assessment and management of marine resources. Some marine species with an apparently continuous distribution actually have local genetically distinct populations across their range, so careful consideration is required in the delineation of MUs. To delineate MUs for Pacific cod (Gadus macrocephalus) in the coastal area of the Sea of Japan, we studied the geographic distribution and genetic variation of the species. Two geographically separate groups were identified based on the analysis of trawl survey data. A spatially explicit clustering analysis of 309 sequences of the mitochondrial NADH dehydrogenase 2 gene identified two groups of samples: one in the central to northern Sea of Japan (NJ) and another in the westernmost shelf area around the Tsushima Strait (WJ). The population structure was further confirmed by analysis of molecular variance and a significant pairwise Φst value between the two groups. The NJ population had experienced a post-glacial population expansion, whereas the WJ population size remained stable, probably reflecting different oceanographic conditions in the two regions. The two populations diverged from each other during the last glacial period, likely due to habitat discontinuity. Finally, based on the species’ genetic population structure and the geographic distributions, we parsimoniously propose that a single boundary be set along the coast of western Honshu Island to divide MUs in the Sea of Japan.

Probabilistic assessment of storm surge potential due to explosive cyclogenesis in the northwest Pacific region

ABSTRACTExplosive cyclones formed in the northwest Pacific region can be categorized into three major types based on their evolution: Type-I cyclones develop over the Sea of Japan, Type-II are generated on the continent and move toward the Pacific Ocean, and Type-III travel northward in the Pacific Ocean along the Japanese archipelago. We performed computational experiments of past storm surges to find statistical features of local sea levels, depending on the types of the cyclone evolution under a realistic meteorological scenario of winter cyclones, with an aim to provide possible sea-level rise expected in the northeast Asia. Here, we show that amplification of local sea level, governed by the orientation of coastal lines with cyclone tracks, is defined by the evolution type that is classified by their trajectories, rather than the intensity, of the cyclone. Nemuro Bay is the most vulnerable site in the northwest Pacific region regardless of the evolution type. Severe storm surges are also expected along certain other semi-enclosed coasts facing the northern Sea of Japan and Sea of Okhotsk due to Type-I cyclones. The probabilistic evaluation of sea levels depending on the cyclone evolution type as introduced in this study may be useful for evaluating potential disasters.

北海道周辺4海域(道東・道南太平洋,北部日本海および南部オホーツク海)における動物プランクトンバイオマスおよび種組成の季節変化と年変動

北海道周辺4海域(道東・道南太平洋,北部日本海および南部オホーツク海)における動物プランクトンバイオマスおよび種組成の季節変化と年変動

Current Data on the Taxonomic Composition and Distribution of the Trawl Macrozoobenthos in Russian Waters of the Sea of Japan

A complex bottom trawl survey (430 stations) was conducted over all of the shelf and continental slope (within a depth range of 10–750 m) in the Russian waters of the Sea of Japan from April 1 to July 8, 2015. A total of 211 taxa of invertebrates were recorded from trawl catches. The most widely represented of them were starfish (36), shrimps (32), gastropods (27), bivalves (23), brachyuran and anomuran crabs (11), polychaetes (11), coral polyps (10), and sponges (10). The total recorded biomass of macrozoobenthos in benthic biotopes of the northern Sea of Japan reached 1 572 500 t (136 600 t in Peter the Great Bay, 341 500 t in the Southern Primorye area, 686 000 t in the northern Primorye area, and 408 400 t in the Western Sakhalin subzone), which is higher than the mean long-term level. The total stock of commercial invertebrates was estimated at 630 000 t. Its largest portion (265 200 t, or 42.1%) was concentrated in the northern Primorye area (western Tatar Strait). The mean specific biomass of the trawl macrozoobenthos constituted 13.5 ± 1.1 g/m2 (including 6.3 ± 0.5 g/m2 of commercial benthic species). The most abundant groups were brittle stars (372 200 t), brachyuran crabs (231 600 t), anomuran crabs (48 700 t), shrimps (226 900 t), sponges (182 900 t), sea lilies (167 500 t), starfish (77 200 t), sea urchins (59 000 t), and bivalves (49 500 t). The vertical distribution of the total benthos and its commercial portion was characterized by maxima in the upper shelf (10–50 m) and within a depth range of 300–400 m. In the northwestern Sea of Japan, 18 biocenotic complexes of trawl macrozoobenthos were identified. The largest areas were occupied by the group of the sedentary seston-feeding sea lily Heliometra glacialis (biomass 5.5 g/m2, depth range of 104–692 m, 131 stations), the group of the polyphagous snow crab Chionoecetes opilio (4.4 g/m2, 27–552 m, 71 stations), the group of the mobile seston-feeding basket star Gorgonocephalus eucnemis (6.6 g/m2, 58–372 m, 40 stations), and the group of the polyphagous pale yellow sea urchin Strongylocentrotus pallidus (4.7 g/m2, 17–351 m, 40 stations).

CURRENT DATA ON COMPOSITION AND DISTRIBUTION OF TRAWL MACROZOOBENTHOS IN THE RUSSIAN WATERS OF THE JAPAN SEA

The bottom trawl survey (430 stations) was conducted over the shelf and continental slope in the Russian sector of the Japan Sea (total depth range 10–750 m) on April 1 — July 8, 2015. In total, 211 taxa of invertebrates were recorded in the trawl catches. Most of them belonged to sea stars (36), shrimps (32), gastropods (27), bivalves (23), crabs and craboids (11), polychaetes (11), coral polyps (10), and sponges (10). The total biomass of macrozoobenthos in the surveyed area was assessed as 1572.5 . 103 t (136.6 . 103 t in Peter the Great Bay, 341.5 . 103 t at southern Primorye, 686.0 . 103 t at northern Primorye, and 408.4 . 103 t at western Sakhalin) that was higher than the mean long-term level. The total stock of commercial invertebrates was assessed as 630.0 . 103 t. Its highest portion (265.2 . 103 t or 42.1 %) was concentrated in the western Tatar Strait. The average biomass of macrozoobenthos was 13.5 ± 1.1 g/m2 , including 6.3 ± 0.5 g/m2 of commercial species. The most abundant groups were basket stars (372.2 . 103 t), crabs (231.6 . 103 t), shrimp (226.9 . 103 t), sponges (182.9 . 103 t), sea lilies (167.5 . 103 t), sea stars (77.2 . 103 t), sea urchins (59.0 . 103 t), craboids (48.7 . 103 t), and bivalves (49.5 . 103 t). Vertical distribution of both total and commercial benthos was distinguished by peaks on the upper shelf (10–50 m) and upper slope (300–400 m). Over the surveyed northern Japan Sea waters, 18 biocoenotic complexes of trawl macrozoobenthos were identified. The largest area was occupied by the complex of immobile sestonophagous sea lily Heliometra glacialis (131 stations in the depth range of 104–692 m with average biomass 5.5 g/m2 ), other wide-spread complexes were those of polyphagous snow crab Chionoecetes opilio (71 stations, 27–552 m, 4.4 g/m2 ), mobile sestonophagous basket star Gorgonocephalus eucnemis (40 stations, 58–372 m, 6.6 g/m2 ), and polyphagous fawn sea urchin Strongylocentrotus pallidus (40 stations, 17–351 m, 4.7 g/m2 ).

Simulation of mesoscale circulation in the Tatar Strait of the Japan Sea

The eddy-resolved ocean circulation model RIAMOM (Lee et al., 2003) is used to analyze seasonal variability of mesoscale circulation in the Tatar Strait of the Japan Sea. The model domain is a vast area including the northern Japan Sea, Okhotsk Sea and adjacent region in the Pacific Ocean. A numerical experiment with a horizontal 1/18° resolution has been carried out under realistic meteorological conditions from the ECMWF ERA-40 reanalysis with restoring of surface temperature and salinity. The simulated seasonal variability of both the current system and mesoscale eddy dynamics in the Tatar Strait is in a good agreement with temperature and salinity distributions of oceanographic observation data collected during various seasons and years. Two general circulation regimes in the Strait have been found. The circulation regime changes from summer to winter due to seasonal change of the North Asian Monsoon. On a synoptic time scale, the similar change of the circulation regime occurs due to change of the southeastern wind to the northwestern one when the meteorological situation with an anticyclone over the Okhotsk Sea changes to that with a strong cyclone. The Lagrangian maps illustrate seasonal changes in direction of the main currents and in polarity and location of mesoscale eddies in the Strait.

Inter-annual and spatial difference in hatch date and settlement date distribution and planktonic larval duration in yellow striped flounder Pseudopleuronectes herzensteini

Hatch date and settlement date distribution and planktonic larval duration (PLD) in yellow striped flounder in nursery grounds in the northern Japan Sea and in the Okhotsk Sea around Hokkaido (Northern Japan Sea–Okhotsk Sea population) were investigated. We examined the relationship between the ecological features and water temperature in these two locations where oceanographic conditions considerably differ. For both nursery grounds, the timing of hatch was early in a warm year and late in a cold year, indicating the strong link between water temperature and the timing of hatch in this population. Although spatial difference in hatch date in 2007 was not significant, hatching and settlement of juveniles collected in the Okhotsk Sea nursery (Okhotsk Sea subpopulation: OSS) occurred later than in those collected in the Japan Sea (Japan Sea subpopulation: JSS); in the spring, the water temperature of the Japan Sea rises earlier in the southern area. The precise area where eggs of both subpopulations originated is unknown; however, this study indicates that eggs that become the JSS may be produced further south than those for the OSS. Comparing on the same date, the water temperature around potential spawning area of OSS in 2006 was ca. 2 °C lower than in 2007 and 2009; however, the overall difference in water temperature at the median date of hatching was 0.7 °C. This result indicates that a spring rise in water temperature probably determines the timing of spawning and larval hatch of this population. Spatiotemporal differences in the PLD were affected by water temperature in which juveniles were exposed during pelagic phase. The PLDs were shorter in warmer years and for warmer subpopulation. The PLD of OSS was longer than that of JSS and spatial difference was statistically significant in 2006. Water temperature in which OSS was exposed in later pelagic phase was relatively low, and the growth of pelagic larvae of OSS was probably slow, and consequently, the PLD of OSS may become long. The eggs originating the OSS are spawned in the Japan Sea and transported a long-distance to their nursery ground in Okhotsk Sea. Generally, a slow growth rate is considered a negative factor for the early survival of fish, although it may be that the slow growth and long PLD of the OSS juveniles confers an advantage upon them during their long-distance transportation. For yellow striped flounder, this study primarily reports on hatch date and settlement date distribution and PLD of juveniles. For flatfish species, the study of the link between those features and water temperature is limited. This study expands the knowledge of the early life-cycle in flatfish, information on which is currently limited.

SEASONAL VARIABILITY OF THE SURFACE WATER CIRCULATION IN THE NORTHERN JAPAN SEA BY DATA OF DRIFTING BUOYS

Data of observations on drifters in 1988–2015 are used to study seasonal variability of the surface water circulation in the Japan Sea. The well-known circulation patterns are observed, as the Tsushima Current, the East-Korean Current, the Primorye Current, and the northern cyclonic gyre. In the fall season (October), the main features of the mean flow are a very strong inflow through the Korean/Tsushima Strait and the intensive Tsushima Current and East-Korean Current. In winter (January), the cyclonic gyre over the norther basin and the Primorye Current along Primorye coast are strengthened. These seasonal changes of the flow field are presumably caused by monsoon winds variation. In spring (April) and summer (July), the water circulation is generally weakened; one of important patterns of the summer circulation in the northern Japan Sea is the westward branch of the Tsushima Current toward Primorye coast.

Orbital time scale records of Asian eolian dust from the Sea of Japan since the early Pliocene

A high-resolution potassium content record of sediments from Integrated Ocean Drilling Program (IODP) Site U1422 drilled in the northern Sea of Japan was employed to yield an astronomical timescale for this ∼205 m thick sedimentary archive. The K content was quantified using the natural gamma radiation (NGR) data routinely measured on DV JOIDES Resolution. The U1422 K (wt.%) series shows an increasing trend with time, which parallels the growth of North Hemisphere ice sheets since ∼4 Ma, as revealed by the global benthic foraminifer's oxygen isotope stack (LR04). We propose that K content variations reflect changes in the relative contributions of Asian eolian dust and volcanic weathering products, in response to changes in global ice volume. Using the shipboard age model, constrained by palaeomagnetism and nanofossils datums, we tuned the U1422 K content variations to the LR04 stack. Our tuned age model for site U1422 goes back to 3.9 Ma. The studied record indicates that Asian dust generation is enhanced during periods of global cooling. The synchronous variations between the U1422 K record and the LR04 stack also suggest that global cooling played a dominant role in promoting the central Asian aridification since ∼3.9 Ma, while the uplift of Tibetan Plateau plays a secondary role, considering many disagreements still exists between the timing and amplitude of the Qinghai-Tibetan uplift and the evolution of central Asian aridity since the early Pliocene.

An Annotated List of Cartilaginous Fishes (Chondrichthyes: Elasmobranchii, Holocephali) of the Coastal Waters of Sakhalin Island and the Adjacent Southern Part of the Sea of Okhotsk

An annotated list of cartilaginous fish (Chondrichthyes: Elasmobranchii, Holocephali) is given for the first time in the 200-year history of studying the ichthyofauna of Sakhalin Island and adjacent waters of the southern part of the Sea of Okhotsk (including the coast of Hokkaido Island) and the northern Sea of Japan. The list includes 43 species in two classes, eight orders, 16 families, and 25 genera. Information on nature conservation status, English and Latin names, depths of habitat, and distribution within the coastal waters of Sakhalin are presented. For a number of species caught off the coast of Sakhalin and in the adjacent waters, information is provided on collection specimens confirming their presence in the region under study. For a number of species of the Rajiformes order (Arctoraja parmifera, A. smirnovi, A. simoterus), the modern ranges and taxonomic status are being refined in the light of new data. The taxonomic status of the so-called “disputed” taxa is discussed as well as the validity of the species considered in the Bathyraja matsubarai complex. Based on the study of the collections, Arctoraja simoterus, previously unknown in the waters of Russia, as well as Myliobatis tobijei, caught in the Bering Sea, has been discovered, which significantly expands the range of this species to the north.

Sea-ice production in the northern Japan Sea

Sinking of the dense water plays a significant role in the global climate system by driving thermohaline (overturning) circulation and biogeochemical cycles. Deep water convection occurs also in the Japan Sea, and the convection has been considered to be mainly caused by intense cooling of the sea surface. Another possible cause of the convection is brine rejection associated with high sea-ice production in a coastal polynya (thin sea-ice) area in the northern Japan Sea. We have developed an algorithm which detects the thin ice area and estimates the thickness using passive microwave satellite data. Based on a heat flux calculation with the satellite-derived ice thickness, the total sea-ice production in winter (December–March) averaged over 2002/03–2010/11 is estimated to be 4.27 × 1010m3. This indicates that the ice production was underestimated by about half in a previous study in which the polynya was unrealistically treated as a low ice concentration area. The main determinant factor for the total ice production is the surface air temperature in early winter (December–January), which shows a rapid warming trend of 0.7°C/decade for this 40-years. Based on a linear regression approach, the total ice production is estimated to have decreased by ~5%/decade due to air temperature warming. If brine rejection due to the ice production contributes to the deep water formation in the Japan Sea, this is consistent with the fact that the deep water formation has been decreasing for the last 50–100 years.

Sea star Henricia spiculifera (Clark, 1901) in the northwestern Pacific: one species or three?

Three species of the sea stars are reported from the waters of the northwestern Pacific. These species were referred by earlier authors as Henricia spiculifera or H. leviuscula spiculifera. Two of them, H. lineata and H. uluudax, were recently described from the Aleutian Islands. These species are reported for the first time from the western Pacific (southeastern Kamchatka shore, Commander Islands, and the northern Kurile Islands). The third species, H. olga sp. n. is herein described from the northern Sea of Japan. It is very likely that similar sea stars recorded in Yellow Sea and the southern Kurile Islands belong to H. olga sp. n. These three species are a part of a phylogenetic clade within the subgenus Setihenricia, which also includes H. sanguinolenta, H. multispina, and several undescribed species occurring in the northeastern Pacific.

Reconstruction of tsunami history based on event deposits in the Niigata area, eastern coast of the Sea of Japan

Although extensive research on tsunami deposits has been conducted on the Pacific coast of Japan, such deposits on the Sea of Japan coast have received little attention. Consequently, little is known about tsunamis along this coastline, especially for events that occurred before the 19th century. The aim of the present study is to enhance this record based on tsunami deposits in Lake Kamo and Iwafune Lagoon in the Niigata area.Based on analysis of six borehole cores, twenty-four likely tsunami deposits that formed during the last approximately 9000 years were identified in Lake Kamo, and nine likely tsunami deposits that from between approximately 9000 and 2200 cal BP were identified in Iwafune Lagoon.The likely tsunami deposits of Lake Kamo and Iwafune Lagoon have revealed the first detailed tsunami history for the last approximately 9000 years in the northern Sea of Japan.

Ridge virtual population analysis to reduce the instability of fishing mortalities in the terminal year

AbstractTuned virtual population analyses are widely used for fisheries stock assessments. However, accurately estimating abundances and fishing mortality coefficients in the terminal year using tuned virtual population analyses is generally difficult, particularly when there is a limited number of available abundance indices. We propose a new method of integrating the tuned virtual population analyses with a ridge regression approach. In our method, penalization in the ridge regression is applied to the age-specific fishing mortalities in the terminal year, and the penalty parameter is automatically selected by minimizing the retrospective bias. Therefore, our method is able to simultaneously obtain a stable estimation of fishing mortality coefficients in the terminal year and reduce retrospective bias. Simulation tests based on the northern Japan Sea stock of walleye pollock (Gadus chalcogrammus) in the Sea of Japan demonstrated that this method yielded less biased estimates of abundances and avoided overestimations of fishing mortality coefficients in the terminal year. In addition, despite limited abundance indices, our method can perform reliable abundance estimations even under hyperstability and hyperdepletion conditions.

Records of Mytilus trossulus (Bivalvia: Mytilidae) and Its Possible Distribution along the Northern and Central Japan Sea Coast of Honshu Island

Records of <i>Mytilus trossulus</i> (Bivalvia: Mytilidae) and Its Possible Distribution along the Northern and Central Japan Sea Coast of Honshu Island