Hover fly fauna (Diptera,Syrphidae) of Karaginskii Island (the Bering Sea)

The hover fly fauna of Karaginskii Island, located in the southwestern part of the Bering Sea near Kamchatka Peninsula, was investigated. A total of 39 species belonging to 22 genera were found on the coastal plain covered with the shrub tundra and meadows of various types. Cheilosia with 7 species was the most diverse genus in the fauna. The chorological structure of the fauna has a typical boreal pattern being dominated by widespread species (77% of the fauna), whereas the fraction of arctoboreal species is distinctly smaller (8%). The subspecies Cheilosia illustrata magnifica, one of the dominants in the hover-fly community (9%), was a single subendemic element of the fauna.     

Ichthyofauna of Russian exclusive economic zone of the Bering Sea: 2. Ecological and zoogeographical characteristics

The ecological and zoogeographical characteristics of 344 species of Pisces and fish-like species comprising the ichthyofauna of the Bering Sea (Russian Exclusive Economic Zone) are presented for the study period of 1995?2012 (original studies) and those for previous findings in this area. The benthic species (elittoral, mesobenthic, and sublittoral; 216 species, or 62.8%) dominate if one takes into account the biotopic characteristics of the species; the majority belongs to the wide-boreal Pacific, wide-boreal Asiatic, and arcticboreal species (255 species, or 74.1%) by the zoogeographic characteristics. The comparative analysis of the fish communities of the western Bering Sea evidences to the significant changes of the ichthyofauna within the depth southwards Navarin Cape. Arctic-boreal species can be considered as a specific faunistic “margin” between the northern and the southern ichthyofauna of the western Bering Sea due to their eurybiont characteristics.     

Biological features of the common fish species in Olyutorsky-Navarin region and the adjacent waters of the Bering Sea: 1. Gadidae (cods) family

Biological features of the three common fish species, pollock Theragra chalcogramma, Pacific cod Gadus macrocephalus, and saffron cod Eleginus gracilis (Gadidae), have been studied using a 20-year dataset (1995?2015). These species inhabit the northwestern Bering Sea in the summer–autumn period and form the schoolings in Olyutorsky-Navarin region. The size–age parameters, as well as the peculiarities of the body length and body weight dynamics, spawning periods, spawning range, and conditions, of the fish caught by different sampling gear have been analyzed. Due to the construction peculiarities and catch efficiency of the different catching gear, the largest specimens are found in the setlines and snurrevads; the fish caught by the trawls are characterized by the smallest size. The body length and body weight of pollock is greater in the pelagic trawl catches compared to the bottom trawl catches. The abundant brood of Gadidae may well be tracked on the multiyear dynamics graphs reflecting the size distribution, as well as by the decrease of biological parameters of the fish. The studied species inhabit the vast growth areas, so smaller body size of them in the coastal waters may be a result of a high ratio of the young specimens there.     

Biological features of the common fish species in Olyutorsky-Navarin region and the adjacent waters of the Bering Sea: 4. family sculpins (Cottidae)

Based on the materials of investigations conducted for 20 years (1995?2015), the features of biology of the common fish species of the family Cottidae from the northwestern Bering Sea are studied. These species are found during summer and fall in the waters of the Olyutorsky-Navarin region. The size–age parameters of the fishes collected with different fishing gears, as well as the features of their body length and body weight dynamics, spawning time, and spawning conditions, are described. The largest exemplars of shorthorn sculpin Myoxocephalus verrucosus and staghorn sculpins, armorhead sculpin Gymnocanthus galeatus and G. detrisus, are recorded in the catches of snurrevads, while the fishes caught in trawls are characterized by smaller size. Interannual variability of the size composition of the fish is related to the abundance of certain generations or to the fishery directed to different associations of sculpins. In the coastal waters, comparatively low average body size is usual for the majority of common sculpin species (with the exception of lords, yellow Irish lord H. jordani and Gilbert’s Irish lord H. gilberti) because of the dominance of juveniles.     

Fish by-catch species from coastal small-scale shrimp trammel net fishery in the Aegean Sea (Izmir Bay, Turkey)

Fish by‐catch from coastal small‐scale shrimp trammel net fishery was estimated from fishery‐dependent surveys in Izmir Bay (Aegean Sea), Turkey, during the 2004 and 2005 fishing seasons. Sampling data were obtained from 170 observations onboard 18 commercial fishing vessels. Fifty‐two species belonging to 31 families of fish, including cephalopods, constituted the by‐catch. Diplodus annularis was the most abundant by‐catch species followed by Loligo vulgaris > Sepia officinalis > Mullus barbatus > Boops boops > and Solea vulgaris. The estimated total ratio of fish by‐catch to shrimp was 1 : 1.09 kg.     

The current status of demersal fish resources in the Russian waters of the Sea of Japan

A bottom trawl survey was conducted over all of the shelf and continental slope in the Russian waters of the Sea of Japan, from Peter the Great Bay to the La Perouse Strait, from March 31 to July 8, 2015. The species composition and biomass of demersal fish were determined for Peter the Great Bay, waters of southern and northern Primorye, and the West Sakhalin subzone. The bulk of the biomass (over 90% of the estimated biomass in the study areas) was formed by four families: Gadidae, Pleuronectidae, Cottidae, and Clupeidae. The highest biomass, 218000 t, was recorded from the West Sakhalin subzone; the lowest, 77400 t, was found from Peter the Great Bay. The proportions of biomasses of the considered species varied substantially between areas: walleye pollock and plain sculpin dominated by biomass in Peter the Great Bay; walleye pollock and scale-eye plaice dominated off southern Primorye; herring dominated off northern Primorye; and scale-eye plaice and speckled founder were dominant in the West Sakhalin subzone. The density of the fish concentration was determined for several bathymetric ranges in the considered areas. In the period of studies, the pattern of distribution of fish in Peter the Great Bay was still of the winter type, which is characterized by high concentrations over the continental slope. There was some shift towards shallower depths in Primorye waters; however, taking the great latitudinal span of the area of the research and the early spring into account, these migrations were not so clearly pronounced, as would be observed in later periods. The most distinct differences in the bathymetric distribution were found in the West Sakhalin subzone, where the distribution pattern corresponded mostly to the summer type with its high concentrations in shallow waters and low ones over the continental slope. According to the estimates in 2015, the biomass of demersal fish slightly increased as compared to the values of the 1980s–1990s.     

The results of zooplankton studies in the Bering Sea under the NPAFC Program (BASIS expedition). Part 1. Eastern areas

Data on zooplankton in the eastern Bering Sea are presented. Samples were collected and processed by the planktonologists of the Pacific Fisheries Research Center (TINRO Center) aboard American vessels in the summer and fall from 2003 through 2011. Based on the analysis of the averaged values of bottom temperature, surface temperature, ice cover index, and also on maps of temperature distribution on the surface and near the bottom, the years 2003–2006 are referred to as “warm” and 2007–2011 as “cold.” A comparison of these two periods showed that with the advent of the “cold” period, the overall stock of zooplankton in the eastern part of the sea grew, particularly in the shelf zone, where it increased more than three times exclusively at the expense of the large fraction. Chaetognaths and copepods constituted the major proportion of this increase; stocks of euphausiids, mysids, hyperiids, and pteropods also grew, while a loss was observed in decapods (larval crabs and shrimps) and coelenterates. In the southern part of the shelf zone, a vast area with a higher biomass of the large fraction occurred, which was mainly due to copepods and chaetognaths. At the same time, areas with denser concentrations were formed by euphausiids and amphipods. The horizontal distribution of small and medium-sized zooplankton almost did not change; meanwhile, the main species of the small fraction, viz., Pseudocalanus newmani and Oithona similis, exchanged their significance and the neritic species Centropages abdominalis, Eurytemora herdmani, and Acartia longiremis, as well as cladocerans and meroplankton (larval Cirripedia, Bivalvia, and Polychaeta) almost completely vanished from the plankton by 2011. In most of cases, the mean biomass of the profiling species of the large fraction (Calanus marshallae, Neocalanus flemingeri, N. cristatus, Eucalanus bungii, Thysanoessa raschii, Themisto libellula, Limacina helicina, and Sagitta elegans) grew during the cold period. In the large fraction, S. elegans constituted half of the biomass (52% in the warm period and 49% in the cold one); the following two species were the copepods E. bungii and C. marshallae (both amounted to 26% and 39%, respectively), while Th. raschii, which is usually predominant among euphausiids, was only the last in the top five species. According to the example of the eastern areas of the sea, it becomes evident that the hyperiid Themisto libellula is brought into the studied area with cold waters from the north and disappears when their inflow stops. This species responds later to cooling and earlier to warming as compared to other species or groups. It appears that the end of the “cold” period can be expected in 2012.     

First record of the mite genus Neharpyrhyncuhus (Acari: Harpirhynchidae) in the Russian fauna

The mites of genus Neharpyrhynchus Fain, 1972 (Acari: Harpirhynchidae) are recorded from Rissia for first time. Two species, N. hippolae sp. n. from Hippolais icterina (Passeriformes: Sylviidae) and N. plumaris (Fritsch) from Fringilla coelebs (Passeroformes: Fringillidae) from N. W. Russia was found. N. hippolae sp. n., female holotype (all measurements in mkm, abbreviations--see Fain e.a., 1999): L 517, W 382, LS 179, WS 325, PA 27, thicker than PI 49 and PE 24, pts smooth, vi, ve [symbol: see text] sci are subequal, about 94, l5 247; propodosomal shield not divided; anterior region of pronotum with rounded verrucosites; venter without scales; legs I-II with 2 free segments and strongly developed lobes at their bases; legs III-IV with one segment, bears 4 and 5 setae respectively (in paratypes number of these setae is variable, 4-5). Male: L 227-254, W 210-219, LS 129-134, WS 170-183, pts are smooth, ve 78-87, sci 83-90, sce 89-95, h 90-110; penis 49-56 long; legs III with 2 free segments, basal segment bears seta, apical segment with 5-6 setae; legs IV with one free segment, it bears 4-5 setae. The new species is closely related to N. pilirostris (Berlese et Trouessart, 1889) and distinguished by characters as follows. N. hippolae sp. n. (female): the setae PI about 2 times are longer than PA and PE; the apical segment of legs III-IV bears 4-5 setae. N. pilirostris: setae PA, PI [symbol: see text] PE are subequal; the apical segment of legs III-IV bears 4 setae only. N. plumaris differs from closely related species N. novoplumaris Moss e.a., 1968 by characters as follows. In female of N. plumaris, the setae PA are subequal to PE and 1.6-1.8 times shorter than PI. In N. novoplumaris, the setae PA shorter than PI and PE.     

Variability of the Characteristics of the First Scale Annulus and Length of Year-Old Fish in the Bering Sea Walleye Pollock Theragra chalcogramma

Geographic and interannual variability of the number of annuli and the radius of the first scale annulus, as well as the retrospective length of year-old walleye pollock from the western, northern, and eastern parts of the Bering Sea, was examined using data for the years 1995, 1996, 1998, and 1999. The characteristics of the first scale annulus were varying. By these parameters, walleye pollock from the western Bering Sea significantly differs statistically from walleye pollock of the eastern Bering Sea. With respect to number of annuli, the radius of the first ring, and the retrospective length of year-old specimens, the walleye pollock from the Navarinskii region occupies an intermediate position between fish from the western and eastern parts of the Bering Sea. Interannual variability of the three parameters was found for walleye pollock from the Navarinskii region.     

Spatial distribution and diversity of commercial demersal fish species in the shelf waters of the Caspian Sea

The Caspian Sea (CS) is a unique ecosystem known for its several fish species, especially sturgeons. To exhaustively manage the fish stocks of this ecosystem, detailed knowledge of species composition, abundance, distribution, and the habitat traits of the living organisms is necessary. This study analyzed the diversity, spatial, and seasonal distribution of commercial demersal fish species, and examined the relationships between community structure and environmental variability in Iranian shelf waters of the CS. For this purpose, seasonally fish sampling took place between 2009 and 2011 with a bottom trawl. Among 11 fish species captured, Chelon spp., Rutilus kutum, and Vimba vimba showed the highest abundances (i.e. 88.49%, 10.67%, and 0.69%, respectively). Univariate and multivariate analyses showed differences in commercial fish assemblages (abundance and species richness) according to seasons and regions. Distance-based Linear Model (DisTLM) showed that eight environmental variables display significant linear relationships with the fauna resemblance matrix (p < .05). Based on AIC criteria, the combination of silt&clay, TOM, longitude, depth, bottom, and surface temperature used to build the parsimonious DisTLM model explain 67.03% of the total variability. The results revealed a biogeographical and temporal gradient from the west to the east and summer to winter, in terms of commercial demersal fish assemblages and species diversity, as a consequence of different geomorphological, bottom substratum conditions and benthic communities.     

Helminthic fauna of commercial fishes from the Saya-de-Malya bank (Indian Ocean)

The data on infestation of 8 species of commercial fishes from Saya-de-Malya bank (the Indian Ocean) are presented. 43 helminth species were identified: 10 Monogenea species, 18 trematode, 7 cestode and 8 nematode species. The mature worms are observed to be related to a certain host, whereas the nematode and cestode larvae have wide specificity. High infestation degree by Anisakis larvae is found in fishes, especially in Carangidae. At the bank area fishes are found to be free from Acanthocephala while those Acanthocephala are found in fishes from other areas of the Indian Ocean which may be attributed to the specific diet at the Saya-de-Malya bank. On the whole the helminth fauna of fishes examined at the Saya-de-Malya bank does not demonstrate the endemic pattern. The most specific helminth species were found in some fish species.     

Biological consequences of organic pollution of nearshore marine ecosystems in the Russian waters of the Sea of Japan

The process of the inflow and accumulation of organic matter in the bays and bights of the Russian coast of the Sea of Japan was evaluated. Changes in the composition and structure of marine communities that take place in certain water bodies of Primorsky Krai were shown using the author’s own material and literature data. The rating of water bodies by the degree of the anthropogenic transformation of biocenoses as a result of the accumulation of organic matter was performed.     

Features of the Biology of Mass Fish Species in Russian Waters of the Chukchi Sea. 1. Commercial Fish Biomass. Family Gadidae

Journal of Ichthyology - Based on the results of research in 1995–2020, mass and potentially commercial fish species have been identified in Russian waters of the Chukchi Sea. Among the 72...     

The formation of the Lycodinae fauna (Perciformes: Zoarcidae) of the Sea of Japan

The subfamily Lycodinae is represented in the Sea of Japan by two genera (Lycodes and Petroschmidtia) and seven species (Lycodes japonicus, L. nakamurae, L. raridens, L. tanakae, L. teraoi, L. yamatoi, and Petroschmidtia toyamensis), which are widely distributed on the shelf and upper continental slope. Based on the geographic and bathymetric distribution of eelpouts of the Sea of Japan and adjacent waters, two groups of closely related species with different types of distribution ranges were distinguished. The first group includes pairs of species that live primarily on the continental slope and are completely isolated in the Sea of Japan or in the Sea of Okhotsk. The second group is comprised of upper interzonal species of the Sea of Japan that are found on the continental slope and shelf, as well as in the southern Sea of Okhotsk from Terpeniya Bay to the southern Kuril Islands. Their related species in the Sea of Okhotsk are mostly found to the north of the Terpeniya Bay. The study of the eelpout distribution and the data on the geological history and paleoclimate of the Far East show that the Lycodinae fauna of the Sea of Japan was formed from North Pacific eelpout-like fishes during the isolation of the sea in the late Pliocene-early Pleistocene, which was concomitant with the general cooling of the Earth’s climate. During the Pleistocene interglacials, the eelpout migrations were unidirectional, from the Sea of Japan to the southern Sea of Okhotsk. The reconstruction of the formation of the Sea of Japan Lycodinae fauna suggests that the related taxa from the Sea of Japan and the Sea of Okhotsk are separate species, while the northern and southern forms of species from the Sea of Japan (Lycodes yamatoi and L. teraoi) are no more than subspecies.     

The cyclopid (Crustacea,Copepoda) fauna of the inland waters of Israel

Four species of the genusMesocyclops (Cyclopoida: Cyclopidae) are reported from Israel:Mesocyclops kieferi Van de Velde, 1984,Mesocyclops aequatorialis similis Van de Velde, 1984,Mesocyclops ogunnus Onabamiro, 1957 andMesocyclops arcanus n.sp. The new species, close toM. kieferi, is described and some remarks are given for the other species.     

Morphological Variability of Stone Cockscomb Alectrias alectrolophus (Stichaeidae) from the Sea of Okhotsk and the Bering Sea

Journal of Ichthyology - The morphological variability (plastic and meristic signs) of stone cockscomb Alectrias alectrolophus has been studied for the representatives from the Sea of Okhotsk and...