Abstract The white-edged rockfish Sebastes taczanowskii Steindachner, 1880 is a marine viviparous teleost, which plays a substantial role in the functioning of subtidal fish communities and is an important recreational fishery species [2]. The biology of S. taczanowskii has been well studied; however, there is no information about the population structure of the species. The aim of our study was to

Abstract A new coastal haul-out site of ringed seals, Pusa hispida (Schreber, 1775), has been found on the coast of Sakhalin Island. Information on the timing of occupancy of the haul-out territory by seals and their number during the season is provided.

Abstract The effect of exposure to acute hypoxia on the level of methemoglobin (MtHb) in blood and the activity of catalase (CAT) and superoxide dismutase (SOD) in erythrocytes of the Black Scorpionfish (Scorpaena porcus, Linnaeus 1758) was studied in experiments in vivo. The O2 concentration in seawater was reduced from 8.5–8.7 mgO2/L to the required values by pumping N2 into the water for 1.5–2.0

Abstract The effects of polyphenolic impurities on the biological activity of fucoidan samples from the brown alga Fucus distichus subsp. evanescens were studied using the model of developing embryos of the sea urchin Strongylocentrotus intermedius. The embryotoxic action of fucophloretol from F. evanescens (IC50 = 96.90 ± 12.20 μmol/L) and cucumarioside A7 (a triterpene glycoside) from Cucumaria frondosa

Abstract The study of diatoms (Bacillariophyta) collected in 2000–2001 with a plankton net from the hypersaline Kara-Bogaz-Gol Bay revealed 13 species and varieties of the genera Campylodiscus, Cocconeis, Diploneis, Epithemia, Navicula, Nitzschia, Planothidium, Surirella, and Tryblionella. These diatoms occurred at water salinities from 44 to 250‰. Consequently, salt-tolerance limits were extended

Abstract The concentrations of Fe, Mn, Cu, Zn, Pb, Cd, and Ni were studied in the brown algae Sargassum miyabei Yendo and S. pallidum (Turner) C. Agardh collected in Ussuri Bay, Sea of Japan, from 2001 to 2018. The degree of heavy metal pollution in different parts of the bay was assessed by comparing the actually measured concentrations of the metals in algae with the upper threshold values of their

Abstract This article presents the results of studies of the cyanobacteria from foulings of natural and anthropogenic substrates of the intertidal zone of the Kola Bay of the Barents Sea for the period from 2010 to 2019. Ninety-five cyanobacterial species from 46 genera, 20 families, and 6 orders were found; 22 species are given for the first time for the Barents Sea. A majority of cyanobacterial taxa

Abstract The problem of the coexistence of closely related species of Paguroidea (Decapoda: Anomura) and the main mechanisms of structuring the communities of these species in sympatry are discussed: differential use of habitats, competition for resources, and physiological resistance to abiotic factors. It is thought that the competition for gastropod shells among hermit crabs may be particularly

Abstract Five consecutive ichthyoplankton surveys were conducted during the spawning season of the walleye pollock Gadus chalcogrammus, in April and May 2019, at a spawning ground off the western coast of the Kamchatka Peninsula. Daily walleye pollock egg production was estimated for each survey based on the number of spawned eggs recorded. The total egg production and mortality rate during embryogenesis

Abstract Hemolymph is one of the main tissues providing invertebrates’ immunity and homeostasis. Earlier, we showed that some of the hemolymph immune parameters of the common Far Eastern mollusk Modiolus kurilensis are sensitive to bacterial and anthropogenic challenges. In this work, a number of cellular parameters such as total hemocyte count (THC), hemocyte phagocytic activity (PA), and reactive

Abstract To assess the biodiversity of symbiotic dinoflagellates (SD) in hydrocorals, we compared the molecular species compositions of four SD lipid classes such as diacylglyceryl-3-O-carboxyhydroxymethylcholine (DGCC), digalactosyldiacylglycerol (DGDG), monogalactosyldiacylglycerol (MGDG), and sulfoquinovosyldiacylglycerol (SQDG) in Millepora dichotoma and M. platyphylla collected in shallow waters

Abstract The possibility of using a battery of biomarkers, that is, the lysosomal membrane stability (LMS), the genetic damage index (GDI), the activities of catalase (CAT) and glutathione-S-transferase (GSТ), the level of malondialdehyde (MDA), and the condition index (CI), was tested for the assessment of pollution in the marine environment. These characters were used to calculate an index reflecting

Abstract Descriptions of ten new and little-known species of macroalgae found during a revision of herbarium and live material collected by the authors from Peter the Great Bay, Sea of Japan, in 2001, 2018, and 2019 are provided in the present report. Of these, seven species are new to the Russian coast of the Sea of Japan, five species are new to the flora of the Far Eastern seas, and three species

Abstract A total of 137 strains of mesophilic and psychrotolerant hydrocarbon-oxidizing bacteria have been isolated from three regions of the Sea of Japan exposed to different levels of anthropogenic pollution. The taxonomic affiliations of the culturable bacteria from surface waters and bottom sediments that are involved in the biodegradation of petroleum hydrocarbons in these regions have been identified

Abstract In order to further understanding of how alga are adjusted to chromium(VI) toxicity at the level of photosynthesis, the pigment content and chlorophyll a (Chla) fluorescence parameters, were studied in Macrocystis pyrifera blades treated with 0, 0.5, 2, 10 and 20 mg/L Cr (VI) solution for 24 h. Results showed that these parameters were clearly affected by different concentrations of Cr (VI

Abstract The values of the osmolality and the contents of sodium, potassium, as well as the contents of the total, free, and bound water fractions in blood serum, muscles, liver, and brain that are characteristic for fish in the sea and in rivers were determined for the far eastern big-scaled redfin, Tribolodon hakonensis. The osmolality associated with the content of inorganic ions (Osminorg) was

Abstract— Otolith shape analysis was conducted with two methods on nine samples of the Mediterranean horse mackerel Trachurus mediterraneus (Steindachner, 1868) caught in Sevastopol and Balaklava bays in 2017–2018. The first method was based on morphometric measurements: length, width, perimeter, and area, which were adjusted to the average fish length from all studied samples; six otolith shape indices

Abstract In this study, Acanthogyrus (Acanthosentis) persicus n. sp. is described from Periophthalmus waltoni Koumans, 1941 in Qeshm Island, Iran. P. waltoni is a species of oxudercine gobies, with a wide range of habitats including mangrove forests and tidal mudflats of the Persian Gulf. It is known as a biological indicator to monitor evolutionary processes. A. (A.) persicus n. sp. is recognized

Abstract The limpet Lottia cf. borealis, a gastropod species widely distributed in the Far Eastern Seas of Russia, has been subjected to genetic analysis. Three genetic markers (COI, 16S, and 12S) showed no evidence of a distinct genetic structure of this species within the studied part of its range (the southern coast of Primorsky Krai and the coasts of Sakhalin Island and the southern Kuril Islands)

Abstract The contents of total lipids and lipid fractions, the intensity of oxidative processes, and the antioxidant defense level in the blood, kidney, spleen, and liver of the Antarctic toothfish Dissostichus mawsoni (Actinopterygii: Nototheniidae) that inhabit stably cold Antarctic waters were studied depending on gender and age. This study revealed no significant differences between males and females

Abstract The ability of fucoidans to scavenge reactive oxygen species still remains a subject of debate in scientific literature, as shown by an analysis of the results of recent studies on the antioxidant activity (AOA) of fucoidans. On the one hand, in vitro and in vivo experiments provide evidence that fucoidans of brown algae can modulate diseases associated with oxidative stress by regulating

Abstract The effect of copper (10, 25 and 50 μg/L) on the population growth, physiological state, and ultrastructure of the microalga Heterosigma akashiwo (Raphidophyceae) were studied. Copper had a greater effect on the mitochondrial membrane potential than on chlorophyll a fluorescence. The neutral lipid content was lower in the exposed cell than in control cells throughout the experiment. The morphology

Abstract The status of the aggregation of the Pacific oyster Crassostrea gigas (Thunberg, 1793) in the Busse Lagoon (Sakhalin Island) was assessed in 2019. The uncontrolled harvesting of this bivalve species caused its abundance to decline. The total oyster stock in the lagoon is estimated at 24.1 t; the commercial stock is estimated at 3.8 t; the aggregation is dominated (84.4%) by nonharvestable

Abstract In July 2019, Vaucheria coronata Nordstedt, 1879, an algal species previously unknown in Russia, was collected in the intertidal zone of Kandalaksha Gulf, the White Sea. The new records significantly expand the range of the species in the Arctic Ocean.

Abstract An endosymbiotic dinoflagellate isolated from the soft coral Stichodactyla haddoni from the coast of Hormuz Island, Strait of Hormuz, Persian Gulf, has been characterized morphologically for the first time. Spherical and egg-shaped cells 6–13 μm in diameter (8–13 μm during mitosis) were recorded. Transmission electron microscopy showed the presence of intracellular organelles including a nucleus

Abstract The reproduction, growth, and variability of the shape of the shell in the gastropod Boreotrophon candelabrum (Reeve, 1848) from Peter the Great Bay (Sea of Japan) were investigated. In aquarium conditions, the mollusks started to lay transparent hemispherical egg capsules in late April at a water temperature of 5.6°C. The females with a shell height of 38–51 mm laid 13–46 egg capsules. The

Abstract Poorly esterified pectin was isolated from the seagrass Phyllospadix iwatensis Makino, 1931 and modified using acidic hydrolysis in 0.5 M HCl. The concentration of anhydrogalacturonic acid, the degree of methoxylation, and the molecular weight distribution were determined in the native and hydrolyzed pectins. The sorption capacity of these pectins with regard to strontium and yttrium ions

Abstract The duration of development, survival rate, and reproductive characteristics of Calanipeda aquaedulcis (Krichagin, 1873) and Arctodiaptomus salinus (Daday, 1885) depending on a diet consisting of monospecific cultures of microalgae from three different taxonomic groups were studied in experimental conditions. The highest survival rates were recorded for the copepod C. aquaedulcis that was

Abstract A brief overview on the history of systematics of the order Gigartinales (Rhodophyta) is provided. The changes in the taxonomy of algae of this order from the Far Eastern seas of Russia based on the molecular phylogenetic data are analyzed. Taxonomic problems that can only be resolved by modern methods are discussed.

Abstract The benthic flora off the Luhuitou Peninsula (Sanya Bay) was studied, for the first time, in areas located opposite a wastewater outlet from fish farm ponds and, thus, heavily polluted with nutrients (dissolved organic nitrogen (DIN), on average 30 μM; orthophosphates, 5.0 μM). Changes in the benthic flora were recorded before and after the farm stopped operation. It was shown that with a

Abstract This paper presents an analysis of the literature data on the Subantarctic fauna of the benthic Myodocopida, including 97 species. The studied fauna is characterized by a high degree but a low level of endemism. The fauna is based on the species of common genera. Ostracods of the families Cylindroleberididae and Cypridinidae lead in the number of species and genera. With depth increase, species

Abstract A method for estimating the integral microalgae biomass beneath a unit surface was designed based on a mathematical model for phytoplankton vital function in the water column and subsequently tested. The model was verified based on data collected during field studies. The results of remote sensing allow extending this method to cover large territories (areas of water). The phytoplankton abundance

Abstract A number of polyphenol fractions were extracted from the brown alga Thalassiophyllum clathrus (Postels & Ruprecht, 1840) by the method of liquid–liquid extraction using solvents of increasing polarity, and their antioxidant activities were studied. The extract obtained with ethyl acetate was characterized by a maximum polyphenol content of 581.2 ± 8.4 mg/g equivalent to gallic acid and a maximum

Abstract An autonomous system of remote audio and video surveillance of marine mammal activity has been designed and installed in the Far Eastern Marine Biosphere Nature Reserve (Peter the Great Bay, Sea of Japan) for monitoring the condition of the spotted seal (Phoca largha Pallas, 1811) population in the reproductive zone. This system makes it possible to collect information on animals without affecting

Abstract The innate immune system plays a vital role to resist the environmental stresses and infectious pathogens in marine mammal pups. To get a baseline level of innate immune capacity in spotted seals, the concentrations of several antioxidant and immune-related factors in the serum of wild and captive spotted seal (Phoca largha) pups from the Liaodong Bay colony were measured and compared. Cu/Zn

Abstract This study aimed to investigate the amino acids contents of some brown (Hormophysa cuneiformis, Sargassum muticum, and Padina minor), red (Digenea simplex, Amphiroa anceps, and Corallina mediterranea), and green macroalgae (Codium elongatum, Ulva fasciata, and Cladophora sp.) collected from the Egypt coasts, using an Eppendorf/Biotronik LC 3000 amino acid analyzer. The results showed that

Abstract The sexual reproduction and life history of the marine pennate diatom Entomoneis cf. paludosa have been described for the first time. The sexual process has been found to involve two gametangia, each producing two gametes. This species is characterized by morphological and behavioral isogamy. Its mating system includes the heterothallic mode of reproduction, with no cases of homothallic reproduction

Abstract Major studies of the Black Sea algal viruses in Russia have been conducted at scientific institutes located in the city of Sevastopol. A review of the methodological approaches used during 2002–2019 shows that both classical virological methods and methods that were recently developed and patented (among them those by the authors) are applicable to the search for, isolation, and study of algal

Abstract The size–age structure, growth, and maturation of the spotted catfish Arius maculatus (Thunberg, 1792) from the Hau River estuary, Mekong Delta, Vietnam, were studied for the first time. A total of 460 fish specimens collected from January to March 2019 were examined. The annuli on the otoliths were visualized; their formation may be related with the alternation of the dry and rainy seasons

Abstract— A new species for the Black Sea, a representative of the Far Eastern fauna, the Korean (dark) rockfish Sebastes schlegelii Hilgendorf, 1880, was found in the coastal zone of Crimea and the Caucasus. The first find of the Korean rockfish took place in 2013; presently, the findings of this species have become more frequent, which suggests a successful introduction. This paper presents the detailed

Abstract The present review considers the physicochemical and biological properties of polysaccharides (PSs) obtained from marine algae (alginates and fucoidans from brown algae; carrageenans from red algae; and ulvans from green algae). These PSs are used in the latest technologies of regenerative medicine (tissue engineering, modulation of drug delivery system, and design of wound dressing materials)

Abstract Low-molecular-weight metabolites known as mycotoxins of micromycetes from the genera Fusarium, Alternaria, Penicillium, Aspergillus, etc. were studied using the enzyme immunoassay in the brown algae Ascophyllum nodosum, Pelvetia canaliculata, Fucus vesiculosus, Laminaria digitata, and Saccharina latissima collected from the Kandalaksha Gulf, White Sea. The T-2 toxin, diacetoxyscirpenol, deoxynivalenol

Abstract The population and biological characteristics of the bivalve mollusk Macoma calcarea (Gmelin, 1791) off the Novaya Zemlya Archipelago, eastern Barents Sea, are considered. The biomass of Macoma clams in the study area varied from 3.9 to 350.6 g/m2; the population density varied from 13.3 to 196.6 ind./m2. It was shown that the biomass and population density of clams do not depend on the depth

Abstract An original method is proposed for rapidly differentiating between regional pink salmon runs with different timings of spawning and states of gonads (gonadosomatic indices, GSI). The results of differentiation obtained by the original and traditional methods are compared. The concept of spatial niches for various temporal groups of Sea of Okhotsk pink salmon in Pacific waters off the Kuril

Abstract This study provides biological, fishery, and production characteristic of spawning females of a triple hybrid between the Russian sturgeon, Siberian sturgeon, and Amur sturgeon (RS × SS) × AS and other commercial hybrid sturgeon forms grown in the cages of a warm-water fish farm in Primorsky Krai, Russia. The survival rate of larvae and juveniles of the triple hybrid in conditions of warm-water

Abstract The current status of the red king crab population off western Kamchatka is considered based on data from bottom trawl surveys and fishery statistics since 2013. Some biological parameters of this crab species are provided; its commercial stock is estimated; some features of red king crab fishery and determination of total allowable catch for the past 7 years are analyzed. The red king crab

Abstract The density and biomass of aggregations of the clam Mya uzenensis have been studied in four areas of the littoral zone in Taui Bay. Aggregations of this bivalve species were mosaically distributed in the form of beds from 0.5 to 5.0 m2 in size. On suitable sediments, Mya aggregations occupied 25–40% of the littoral zone area. The structure of aggregations in the littoral zone of Ola Liman

Abstract The distribution of fish and prawn in the bed of the lower Amur River (within 40–960 km from the mouth) is described based on the results of a beam-trawl survey (57 trawl taw at depths of 1.5–23.0 m) conducted in September and October 2003. A total of 2584 ind. of 22 fish species and 1077 ind. of one invertebrate species (the prawn Palaemon modestus) were caught. The most frequently occurring

Abstract The dynamics of the Atka mackerel stock in the Olyutorsky–Navarin area in 1994–2019 is inferred from bottom-trawl surveys, fishery statistics, open-access NOAA data, and the results of simulation by the method of virtual population analysis. After the period of low stock in the mid-1990s, the abundance of the Atka mackerel group in the area increased sharply to a maximum in 2006–2008, when

Abstract The effect of water temperature on the timing of spawning and spat settlement of the Yesso scallop (Mizuhopecten (=Patinopecten) yessoensis Jay, 1857) in Minonosok Cove (Posyet Bay, Peter the Great Bay) has been studied based on the most complete dataset of observations for 1970–2011. The date of onset of spawning varied from May 1 to June 9 (within 40 days) and the onset of spat settlement

Abstract An aerial survey of Pacific salmon spawning grounds in the main watercourses that empty into the Bering Sea was conducted for the first time since 1992. The total flight time was 35 h; the approximate total length of transects was 3800 km. The number and distribution of Pacific salmon spawners in the Anadyr, Velikaya, Tumanskaya rivers and in the Meynypilgyno lake–river system have been assessed

Abstract A spawning ground of the Mud Skate Bathyraja taranetzi and the Okhotsk Skate B. violacea was recorded for the first time from Pacific waters off the northern Kuril Islands. It was located at 50°25′7″ N, 157°22′7″ E, and a depth of 350–351 m; the water temperature was 3.8°C. At the spawning ground, egg cases and recently hatched juveniles were found in large numbers.

Abstract The spectrum of proteinases and the dynamics of proteinase activity in the ambulacrum structures were studied by quantitative gel zymography in the holothurians Eupentacta fraudatrix and Cucumaria japonica under normal conditions and after transverse cutting of the ambulacrum. Proteinases with gelatinolytic activity were detected only in E. fraudatrix; the species had two pools of proteinases

Abstract The present study is aimed to investigate the effects of iron nanoparticles (Fe-NPs) on growth performance, liver histopathology and some blood parameters of the stellate sturgeon (Acipenser stellatus) juvenile. A total of 144 fish (182.09 ± 9.05 g) were fed diets containing graded levels of Fe-NPs (0, 25, 50, and 100 mg kg–1 diet) for 8 weeks. No significant differences were observed in weight

Abstrac— Intensive algal sampling was conducted from 2017 to 2019 in coastal waters of Wuzhizhou Island (South China Sea, China). In total, 183 species of marine macrophytes, 9 species of Cyanobacteria and 2 species of seagrasses were found. The collection of benthic macroalgae was comprised of 63% of Rhodophyta, 12% of Phaeophyceae, and 25% of Chlorophyta. Among macrophytes, the largest number of

Abstract The growth parameters were determined separately for the two sexes of Penaeus kerathurus, as well as for the two (northeastern and southern) substocks of the species in Tunisia. Seasonal sampling from catches of this species in the coastal and the offshore waters was carried out during the period between 2010 and 2012 for the northeastern substock and between 2010 and 2014 for the southern

Abstract This study reports recent data on the distribution and breeding abundance of seven species of colonial birds on the coast of Peter the Great Bay, Sea of Japan. Over the past 30 years, three species of cormorants (great, Japanese, and pelagic cormorants), as well as the black-faced spoonbill, have significantly increased their numbers. The number of breeding pairs of gray heron and Chinese

Abstract This article provides results of a helminthological study of two seabird species, the Black-Legged Kittiwake (Rissa tridactyla Linnaeus, 1758) and the Brünnich’s Guillemot (Uria lomvia Linnaeus, 1758), from Russkaya Gavan Bay, Severny Island, Novaya Zemlya Archipelago. A total of five species of helminth parasites were identified in kittiwakes and six species in guillemots. The cestode Tetrabothrius

Abstract The summarized composition of the fish fauna of the Karkinitsky Gulf of the Black Sea was established for the first time on the basis of literature and original data for the entire period of research; 108 fish species were recorded in total. Twenty-three new fish species, among them representatives of the Mediterranean faunistic complex, form the basis of the faunistic diversity of the western

Abstract Several fundamentally different pathways may exist to restore a lost structure in closely related species or within the same species of multicellular animals; this phenomenon is described using the example of the echinoderm digestive system. We propose to call this phenomenon “variability of regeneration mechanisms.” In echinoderms, it is manifested as differences in the spatial organization