scholarly journals Knowledge on the Biological and Fisheries Aspects of the Japanese Sardine, Sardinops melanostictus (Schlegel, 1846)

2021 ◽  
Vol 9 (12) ◽  
pp. 1403
Author(s):  
Ousmane Sarr ◽  
Richard Kindong ◽  
Siquan Tian
Keyword(s):  
Pacific Ocean ◽  
Sea Of Japan ◽  
North Pacific Ocean ◽  
Marine Ecosystem ◽  
Biological Information ◽  
The Sea Of Japan ◽  
Japanese Sardine ◽  
Additional Information ◽  
The North ◽  
Management Measures

Japanese sardine (Sardinops melanostictus) is a significant small pelagic fish and a valuable resource that plays an essential ecological role in the marine ecosystem. It is present in the far Eastern Asian maritime waters, including the Pacific Ocean, Sea of Japan, and the East China Sea. Encircling nets, particularly purse seines, are the most used fishing equipment to catch this species. Their fishing grounds are located entirely in coastal areas. Japanese sardine catches have shown varying trends over the last five decades, with a high frequency of captures occurring in the 1980s before collapsing in the early 1990s. The economic and ecological importance of this species has prompted much research, which provided additional information about their spawning migration, distribution, fisheries, and biology. This research was mostly undertaken in the Sea of Japan and its adjacent waters spanning in the north Pacific Ocean. Despite all this research and the importance of this species in its habitats and in commercial fisheries, there is a lack of a recent review presenting the status of global fisheries and biological information for this species. This paper summarizes and updates information on the global geographical distribution, biological aspects, trends in catches, stock fluctuations and assessment, and management measures of the Japanese sardine population. This paper also summarizes information related to the influence of environmental factors on the occurrence of this species and also identifies information gaps. Further research directions are also discussed in this work, which may help improve the knowledge of Japanese sardine and establish rational management measures for their conservation.

Different profiles of naturally produced and anthropogenic organohalogens in the livers of cetaceans from the Sea of Japan and the North Pacific Ocean

2018 ◽  
Vol 136 ◽  
pp. 230-242 ◽  
Author(s):  
Yukiko Fujii ◽  
Yoshihisa Kato ◽  
Mai Kozai ◽  
Takashi Matsuishi ◽  
Kouji H. Harada ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Sea Of Japan ◽  
North Pacific ◽  
North Pacific Ocean ◽  
The Sea Of Japan ◽  
The North ◽  
The North Pacific

scholarly journals Rapid recirculation of FNPP1 derived radiocaesium suggesting new pathway of subtropical mode water in the western North Pacific to the Sea of Japan

2017 ◽  
Author(s):  
Yayoi Inomata ◽  
Michio Aoyama ◽  
Yasunori Hamajima ◽  
Masatoshi Yamada
Keyword(s):  
Pacific Ocean ◽  
Sea Of Japan ◽  
North Pacific ◽  
Western North Pacific ◽  
North Pacific Ocean ◽  
137Cs Activity ◽  
The Sea Of Japan ◽  
Mode Water ◽  
Western North Pacific Ocean ◽  
Subtropical Mode Water

Abstract. The rapid recirculation of 137Cs derived from the Fukushima Nuclear Power Plant Accident (FNPP1-137Cs) occurred in the Sea of Japan (SOJ) in several year timescale after released to the environment in March 2011. The recirculation of FNPP1-137Cs had started in 2012 and reached to the maximum in 2015/2016 in the East China Sea (ECS) and the western North Pacific Ocean. The recirculation of FNPP1-137Cs has been still continued in the coastal site of Sea of Japan in the year of 2016. The re-circulated FNPP1-137Cs activity concentrations showed subsurface peak in the seawater of which density correspond to the Subtropical Mode Water (STMW). These suggests that FNPP1-137Cs injected into the western North Pacific Ocean at south of Kuroshio were subducted into ocean interior just after the accident, then transported southward/southwestward. A part of FNPP1-137Cs in STMW entered into the ECS between Kyushu Island and Okinawa Islands. Then it obducted in the region west of Kyushu Island, north of the ECS, following then entered into the SOJ associated with northward transport with Tsushima Warm Current in several year time scale. This rapid pathway might be new finding of transport process from the western North Pacific Ocean to the SOJ. Almost same value of the 134Cs / 137Cs activity ratio in the coastal region of the Japanese islands (ECS, SOJ, and Ogasawara) also support this re-circulation route. The integrated amount of FNPP1137Cs entered in the SOJ until 2016 was estimated to be 0.21&thins;± 0.03 PBq, which corresponds to 5.1 (3.4–8.0) % of the total amount of FNPP1-137Cs in the STMW. The integrated amount of FNPP1-137Cs back to the North Pacific Ocean through the Tsugaru Straight in the surface layer was 0.1 ± 0.02 Bq, which corresponds to 0.6 (0.4–1.0) % of the total amount of FNPP1-137Cs in the STMW.

scholarly journals Neural Network Approach to Retrieving Ocean Subsurface Temperatures from Surface Parameters Observed by Satellites

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 388
Author(s):  
Hao Cheng ◽  
Liang Sun ◽  
Jiagen Li
Keyword(s):  
Neural Network ◽  
Pacific Ocean ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Sea Surface ◽  
Satellite Measurements ◽  
Surface Parameters ◽  
The North ◽  
The North Pacific ◽  
Bpnn Model

The extraction of physical information about the subsurface ocean from surface information obtained from satellite measurements is both important and challenging. We introduce a back-propagation neural network (BPNN) method to determine the subsurface temperature of the North Pacific Ocean by selecting the optimum input combination of sea surface parameters obtained from satellite measurements. In addition to sea surface height (SSH), sea surface temperature (SST), sea surface salinity (SSS) and sea surface wind (SSW), we also included the sea surface velocity (SSV) as a new component in our study. This allowed us to partially resolve the non-linear subsurface dynamics associated with advection, which improved the estimated results, especially in regions with strong currents. The accuracy of the estimated results was verified with reprocessed observational datasets. Our results show that the BPNN model can accurately estimate the subsurface (upper 1000 m) temperature of the North Pacific Ocean. The corresponding mean square errors were 0.868 and 0.802 using four (SSH, SST, SSS and SSW) and five (SSH, SST, SSS, SSW and SSV) input parameters and the average coefficients of determination were 0.952 and 0.967, respectively. The input of the SSV in addition to the SSH, SST, SSS and SSW therefore has a positive impact on the BPNN model and helps to improve the accuracy of the estimation. This study provides important technical support for retrieving thermal information about the ocean interior from surface satellite remote sensing observations, which will help to expand the scope of satellite measurements of the ocean.

scholarly journals Nursery origin and population connectivity of swordfish Xiphias gladius in the North Pacific Ocean

2021 ◽  
Author(s):  
R. J. David Wells ◽  
Veronica A. Quesnell ◽  
Robert L. Humphreys ◽  
Heidi Dewar ◽  
Jay R. Rooker ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Population Connectivity ◽  
The North ◽  
Xiphias Gladius ◽  
The North Pacific
Sign in / Sign up

Export Citation Format

Share Document