scholarly journals ONCE AGAIN ON FACTORS LIMITING THE NUMBER OF PACIFIC SALMONS (ONCORHYNCHUS SPP., FAM. SALMONIDAE) DURING THE OCEANIC PERIOD OF THEIR LIFE

2019 ◽  
Vol 196 ◽  
pp. 3-22 ◽  
Author(s):  
V. P. Shuntov ◽  
O. S. Temnykh ◽  
S. V. Naydenko
Keyword(s):  
Pink Salmon ◽  
Food Resources ◽  
Point Of View ◽  
The North ◽  
Trophic Networks ◽  
Ecosystem Studies ◽  
Competition For Food ◽  
Far Eastern ◽  
The North Pacific ◽  
Far Eastern Seas

Two different views on factors limiting the abundance of pacific salmons in the marine period of their life are compared. According to traditional point of view, food resources are limited in the marine and oceanic epipelagic biotopes, so a strong competition for food exists between different species of genus Oncorhynchus or between pink salmon O. gorbuscha and other species that makes theIr abundance lower and biological conditions worse. Negative anomaly of the sea surface temperature is considered traditionally as a factor controlling the salmons distribution in the ocean because of the food supply worsening. The other point of view is proposed by authors in the 1980s and is based on comprehensive ecosystem studies of the Far Eastern Seas and the North Pacific. Following to this view, the food resources do not limit the abundance of salmons, which play secondary roles in trophic networks within the subarctic epipelagic layer. Besides, these data do not confirm stenotherm habits of salmons, particularly in conditions of low temperature (salmons could be found in the northern Bering and Okhotsk Seas even in winter). In favor of the latter view, new data are presented for 2018, when the highest biomass of the Russian salmons was observed, primarily due to pink salmon abundance, and the absolutely record Russian catch of pacific salmons in 677,200 t was landed.

scholarly journals Regional differences in climate factors controlling chum and pink salmon abundance

2011 ◽  
Vol 68 (6) ◽  
pp. 1131-1137 ◽  
Author(s):  
Masa-aki Fukuwaka ◽  
Toshiki Kaga ◽  
Tomonori Azumaya
Keyword(s):  
North Pacific ◽  
Regional Differences ◽  
Global Climate ◽  
Regional Climate ◽  
Regional Scale ◽  
Pink Salmon ◽  
Climate Indices ◽  
Climate Factors ◽  
The North ◽  
The North Pacific

Abstract Fukuwaka, M., Kaga, T., and Azumaya, T. 2011. Regional differences in climate factors controlling chum and pink salmon abundance. – ICES Journal of Marine Science, 68: 1131–1137. Chum and pink salmon abundances vary on a decadal time-scale. We examined the relationship between large-scale climate indices (CIs), regional climate factors (RFs), and rates of change in regional catches (RCs) of chum and pink salmon in five regions of the North Pacific. Correlation coefficients of RCs with RFs were larger than those of RCs with CIs, although the correlation coefficient of particular variables varied among regions. Climate affected salmon stocks as indicated by significant relationships with various terrestrial and ocean climate factors on a regional scale. These results suggest that no single CI or RF controls salmon abundance in all regions; however, global climate changes could affect regional climate directly and regional salmon abundance indirectly. A warming trend in the North Pacific might affect the long-term change in salmon abundance. The mechanisms controlling regional salmon abundance must be understood better to forecast successfully future conditions for Pacific salmon stocks, because the response of salmon stocks to global climate change varies among regions.

The Effect of Measured Whipping and Springing on LNG Vessels

2013 ◽  
Author(s):  
Gaute Storhaug ◽  
Narve Oma ◽  
Bjarne Blomberg ◽  
Kazuhiro Hirota
Keyword(s):  
Fatigue Damage ◽  
North Atlantic ◽  
Wind Waves ◽  
Point Of View ◽  
Strain Sensors ◽  
General Level ◽  
Structural Members ◽  
The North ◽  
The Relationship ◽  
The North Pacific

Strain measurements of structural members onboard two LNG vessels have been collected for a period of 5 years. The vessels have been sailing in the world wide trade except for the North Pacific area. The time spent in the North Atlantic is about 40%, which is higher than for typical LNG vessels. The vessel speed has been relatively low in average and well below the service speed, still the effect of springing and whipping has been significant on the fatigue and extreme loading. Previously, results from the strain sensors have been presented versus the fatigue and extreme loading on a general level, independent on the environmental conditions. In this paper the focus is more towards how the vessel behaves in wind/waves with respect to springing and whipping in order to understand more of the relationship between accumulated fatigue damage, heading and loading condition. The vessels have been equipped with wave radars and wind sensors. The effect of whipping and springing on accumulated or part fatigue damage versus relative heading is demonstrated. The effect as a function of the wave height/wind speed is shown for selected headings. One of the objectives is to check if the wind sensor can be a useful alternative to the wave sensor to capture the physics. Some of the data is studied for ballast and cargo condition separately in order to see if these loading conditions can be merged, which is desirable from an assessment point of view.

scholarly journals Nematodes of common Hexagrammidae species from the Far-Eastern Seas of Russia

2014 ◽  
Vol 176 (1) ◽  
pp. 216-224
Author(s):  
Galina F. Solovyeva ◽  
Zoya I. Motora
Keyword(s):  
Japan Sea ◽  
Anisakis Simplex ◽  
The North ◽  
Pseudoterranova Decipiens ◽  
The Japan Sea ◽  
Pleurogrammus Azonus ◽  
Contracaecum Osculatum ◽  
Far Eastern ◽  
First Time ◽  
Far Eastern Seas

Nematoda parasites of five greenling species from the Far-Eastern Seas ( Pleurogrammus azonus , P . monopterygius , Hexagrammos octogrammus , H . lagocephalus , H . stelleri ) are investigated. The family Hexagrammidae is endemic for the North Pacific. In total, 10 species of nematodes are found: Anisakis simplex l., Pseudoterranova decipiens l., Hysterothylacium aduncum , Contracaecum osculatum l., Ascarophis filiformis , A. curvicauda , A. pacifica , Cucullanellus minutus , Cucullanus heterochrous , and Paracapillaria helenae , all of them have wide geographical and hosts distribution. Anisakis simplex l. and Pseudoterranova decipiens l. are the most common for all investigated host species. The highest species diversity of nematodes (7 species) is registered for arabesque greenling P. azonus , particularly its females; Contracaecum osculatum l. and Cucullanus heterochrous are found for the first time for this host in the Japan Sea. The parasites are dispersed irregularly in muscles of all parts of fish body. Large-sized (i.e. elder) fish is higher infected by larvae of P. decipiens .

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