SIZE-AGE STRUCTURE IN SAFFRON COD COMMERCIAL AGGREGATIONS IN THE WESTERN BERING SEA IN 2003–2012
SAFFRON COD, SIZE AND AGE COMPOSITION, DANISH SEINE, FYKE NET, KARAGINSKY GULF, SHELF OF THE KORYAK HIGHLAND
Size and age structure of saffron cod from Danish seine and fyke net catches in the Western Bering Sea has been analyzed on the data for 2003–2012. The body length of the fish in summer and autumn Danish seine catches varied as 13–49 cm in Karaginsky Gulf and as 21–51 cm on the coast of Koryak Highland. The ages of the fish in the catches were 2+–11+ and 2+–12+ respectively. The body length of the fish in winter and spring fyke net catches in Ossora Bay (Karaginsky Gulf) varied as 15–49 cm, and the age of the fish was 1–9 years. The Danish seine catches of saffron cod on the coast of Koryak Highland consisted of commercial sized fish only; the bycatch of none commercial sized fish in Karaginsky Gulf did not exceed tenths of percent in the Danish seine fishing and of 1.4% in the fyke net fishing. There is no difference revealed between the Danish seine and the fyke net catches in size composition of 2+–5+ saffron cod individuals as a basis of the commercial stock of this species in Karaginsky Gulf.
GROUWTH AND PRODUCTION OF COMMON SPECIES OF FLATFISHES (PLEURONECTIDAE) OF THE NOSERN PART OF THE SEA OF OKHOTSK
R.R. Yusupov, Yu.K. Semenov, Yu.A. Shilin
FLATFISH, GROWTH, BIOMASS, PRODUCTION
On the basis of material collected in 1977 and 2002–2014 years studied the growth and formation of somatic production 7 flatfishes mass species, that live in the northern part of the Sea of Okhotsk. It was found that, depending on the rate of weight growth and the rate of natural decline with age fish, flatfish between species observed enough significant differences in the asymmetry of parabolic curves of biomass dynamics that characterize the different rate of increase of biomass and its loss. The largest amplitude of these changes are observed in the polar swing flounder, and the lowest trajectory of growth and biomass loss observed in longlived halibut. In general, the studied species aggregate amount of somatic products produced by all generations per year, roughly equal proportions of individual’s products remaining in the system and disposed of it due to natural mortality, with a slight excess of this value in the latter. The magnitude of the P/B ratio flounder northern Sea of Okhotsk significantly inferior to similar types of western Kamchatka shelf. The data obtained suggest that the relatively low value of stocks of northern flounders due not only to adverse conditions of their habitat in early ontogeny, and consequently high mortality of early juveniles, but also a lower rate of formation of somatic production in conditions of the northern part of the Sea of Okhotsk
ANALYSIS OF VARIABILITY OF THE NUCLEOTIDE SEQUENCE OF THE GENE FRAGMENT CYTOCHROME C OXIDASE I (COI) MTDNA FROM THE PACIFIC HALIBUT (HIPPOGLOSSUS STENOLEPIS) IN THE SEA OF OKHOTSK
S.P. Pustovoit, R.R. Yusupov, A.I. Kaika
PACIFIC HALIBUT, CYTOCHROME C OXIDASE I (COI) MTDNA, THE SEA OF OKHOTSK
The nucleotide sequences mitochondrial cytochrome C oxidase I (COI) mtDNA of the Pacific halibut was founded. Nucleotide diversity of halibut of the Sea of Okhotsk was π=0.00495. It is shown that the amount of variability in nucleotide sites in individuals Pacific halibut influence nonselective factors such as mutation or migration process.
THE RATES OF THE OOGENESIS OF JUVENILE PACIFIC SALMON IN THE SEA OF OKHOTSK IN THE FALL PERIOD IN 2011–2013
S.B. Gorodovskay, A.S. Sushkevich
PACIFIC SALMON, OOCYTES, GONAD DEVELOPMENT RATE, JUVENILE, FALL PERIODOF FEEDING AT SEA
It is first time when differences in the rates of oogenesis have been demonstrated for juvenile representatives of Pacific salmon species with different life cycles in the fall period of their feeding at sea on the base of hystological analysis of gonads. Gonads of immature chum salmon individuals have been analyzed for the fall period of their feeding in the waters of the Sea of Okhotsk.
RECENT DATA ABOUT MOULTING OF NORTH SHRIMP PANDALUS BOREALIS ON THE WESTERN COAST OF KAMCHATKA
NORTH SHRIMP, WEST KAMCHATKA, MOULTING, JUVENILE INDIVIDUAL, MALE, TRANSIT INDIVIDUAL, FEMALE, COMMERCIAL INDIVIDUAL
The paper provides recent extanded data on the time of moulting of north shrimp, obtained on West Kamchatka for the period 1993–2013 in the course of research survey and monitoring over commercial fishery. Dynamics of moulting processes has been analyzed and timings of moulting in all functional groups of north shrimp have been figured out. It has been provided analysis of moulting for commercial individuals, and it has been demonstrated that mass moulting of north shrimp on West Kamchatka starts some earlier, than formerly thought.
CURRENT COMPOSITION OF THE ICHTHYOFAUNA OF AVACHINSKAYA BAY (SOUTHEAST KAMCHATKA)
A.M. Tokranov, B.A. Sheiko
AVACHINSKAYA BAY, SOUTHEASTERN KAMCHATKA, ICHTHYOFAUNA, SPECIES COMPOSITION
Current composition of ichthyofauna of Avachinskaya Bay (Southeastern Kamchatka) is considered on the base of data obtained for the period 1990–2005 and compared to results for the 1930th. One species of lampreys and 76 species of fishes of 23 families are registered. The comparison allows to make conclusion of general similarity (78% approximately) between species composition of ichthyofauna in early XX century and in late XX – early XXI centuries. The basis of the similarity (respectively in 74 and 78%) was formed by representatives of 10 families. Meantime, in some sites of the bay affected anthropogenic influence the abundance and the diversity of species has been decreased in 1990–2000th comparing to the 1930th.
SPECIES DIVERSITY AND SEASONAL DISTRIBUTION OF SEA POACHER OF AGONIDAE (SCORPAENIFORMES) FAMILY IN THE WATERS OF TATARSKIY STRAIT
SEA POACHER, TATARSKIY STRAIT, DISTRIBUTION, BIOMASS
Sea poachers represent group of poor-studied fish inhabiting the coastal waters of West Sakhalin. Last investigations have demonstrated Freemanichthys thompsoni, Podothecus sturioides, Tilesina gibbosa, Percis japonicusand Podothecus veternusas the most abundant species of the Agonidae family there. All mentioned species have seasonal aggregations in most cases in the south-western waters of the island. The biomass of the species can reach 62.2–131.7 tons and represent 53.3% of the total biomass of agonids within the area.
INFORMATION ABOUT SPAWNING OF WINTER COHO SALMON IN THE BASIN OF KAMCHATKA RIVER IN JANUARY 2015
E.А. Shevlyakov, S.V. Shubkin, I.N. Kireev, I.N. Yanchenko
KAMCHATKA RIVER, WINTER COHO SALMON, LATE SEASONAL MORPH, SPAWNERS, SPAWNING, SPAWNING GROUNDS
Results of visual counting coho salmon individuals of late morph in the upper reaches of Kamchatka River in Janyary 2015 are represented. There were 2500 m2 of spawning grounds observed from the river shores to estimate the abundance of spawning coho salmon on the plot of 70 kms from Milkovo Settlement to Sharomy Village. An expert estimation is provided for the abundance of the late morph of coho, entering the Kamchatka River basin. Biostatistical data are collected and age composition of spawners is figured out.
TARGET STRENGTH MEASUREMENTS OF WALLEYE POLLOCK (THERAGRA CHALCOGRAMMA) IN AVACHA GULF AT 38 AND 120 KHZ
M.I. Malin, I.V. Roy, O.M. Lapshin
HYDRO-ACOUSTIC SURVEY, TARGET STRENGTH, WALLEYE POLLOCK, PACIFIC COD, AVACHINSKY GULF
Target strength (TS) measurements in situof walleye pollock have been made using 38 and 120 kHz split beam echosounders. The target strength measured at 120 kHz is around 2.3 dB lower than at 38 kHz. The TS to fork length (FL) relationship for walleye pollock in the Avacha Gulf TS = 20·log10 (FL) – 62 is proposed for both 38 and 120 kHz equipment.
AQUATIC BIOLOGICAL RESOURCES AS COMMON-POOL RESOURCES
COMMON-POOL RESOURCES, ACCESS MODE, AQUATIC BIOLOGICAL RESOURCES, SOCIAL DILEMMAS
Over-exploitation of aquatic biological resources is considered from the perspective of the problems of resources sharing. Movable nature of much of living aquatic resources limits the possibility of excluding users not only on the high seas. Game theory, the development of rules and regulations in line with institutional economics can be used as tools of economic development sustainable use of living aquatic resources.
SUMMER PHYTOPLANKTON OF THE NORTHERN PART OF WEST KAMCHATKAN SHELF IN 2008
OKHOTSK SEA, WEST KAMCHATKAN SHELF, PHYTOPLANKTON, DOMINANT COMPLEXES, ABUNDANCE,BIOMASS, SPATIAL DISTRIBUTION
Monitoring of phytoplankton on West Kamchatkan shelf was accomplished on a local area in the north-east part of Okhotsk Sea and covered all spring and summer stages of algae plankton development from spring maximum in the course of “blossoming” in late May until seasonal minimum in late August. In 2008 the summer plankton on the shelf revealed 97 microalgae species and subspecies from 7 classes. The pool included representatives of Bacillariophyceae (76), Dinophyceae (15), Dictyochophyceae (1), Chrysophyceae (1), Euglenophyceae (1), Cryptophyceae (1), Prymnesiophyceae (2). In late May (period of “blossoming”) the plankton algae were concentrated in the epipelagic zone, in early summer (mid June) — in the layer of temperature jump, and in late summer (the third decade of August) — in the demersal layer. The quantitative characteristics of the phytoplankton varied within wide ranges: the abundance was from 1 to 107 cells/l, the biomass — from 0.001 to 23 825 mg/m3. The maximum biomass of the autotrophic plankton (up to 23 g/m3) was revealed in the surface layer in late May, what is typical for productive high latitude zones of World ocean, including the northern part of the West Kamchatkan shelf. The qualitative characteristics of the phytoplankton (species diversity, abundance and biomass) demonstrated similar dynamics in all stations: a decrease from early to late summer (vegetative) period, according to natural seasonal dynamics of marine boreal populations of microalgae. The irregular distribution of the microalgae species within the area of the monitoring on the West Kamchatkan shelf should be taken into account in the course of exploration of oil and gas deposites on this site.
REPRESENTATIVES OF CALONEIS CL. (BACILLARIOPHYCEAE) IN THE RESERVOIRS OF BERINGIA
CALONEIS (BACILLARIOPHYCEAE), SPECIES COMPOSITION, BERINGIA
An annotated list of 72 species and intraspecies taxa of the genus CaloneisCl. (Bacillariophyceae) identified in the waters of Beringia is given. Approximately 18% of the provided taxa are usual for the given region. Occurrence of the 70% is estimated as “very rarely”. The percent of species and subspecies identified solely in water bodies of Asian part of the Beringia region does not exceed 18%, the same percent for American zone amounts up to 29%.
SOME RESULTS OF STATISTICAL PROCESSING (1972–2014) THE DATA ON THE ICE EXTENT IN THE SEA OF OKHOTSK
THE SEA OF OKHOTSK, ICE EXTENT, CORRELATION ANALYSIS, REGRESSIONEQUATION
The paper has demonstrated statistics on the ice extent in the Sea of Okhotsk averaged by ten-day periods. Strong positive linear correlations have been revealed between the ice extent values for adjacent ten-day periods. Statistical characteristics of the averaged values of the ice extent in the Sea of Okhotsk and coefficients of correlation and determination were calculated, and regression equations were obtained to predict the ice extent area on the base of the value for the former ten-day period. It was found that the variability of the current sea ice extent area was in 70–92% determined by the variability for the former ten-day period.