scholarly journals Genetic analysis of stock structure of blue shark (Prionace glauca) in the north Pacific ocean

2015 ◽  
Vol 172 ◽  
pp. 181-189 ◽  
Author(s):  
J.R. King ◽  
M. Wetklo ◽  
J. Supernault ◽  
M. Taguchi ◽  
K. Yokawa ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Genetic Analysis ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Stock Structure ◽  
Blue Shark ◽  
Prionace Glauca ◽  
The North ◽  
The North Pacific

scholarly journals Isotopic Tracers Suggest Limited Trans-Oceanic Movements and Regional Residency in North Pacific Blue Sharks (Prionace glauca)

2021 ◽  
Vol 8 ◽  
Author(s):  
Daniel J. Madigan ◽  
Oliver N. Shipley ◽  
Aaron B. Carlisle ◽  
Heidi Dewar ◽  
Owyn E. Snodgrass ◽  
...  
Keyword(s):  
Stable Isotope ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Niche Overlap ◽  
Isotopic Niche ◽  
Isotopic Tracers ◽  
Blue Shark ◽  
Prionace Glauca ◽  
The North ◽  
The North Pacific

Blue sharks (Prionace glauca) are globally distributed, large-bodied pelagic sharks that make extensive migrations throughout their range. In the North Pacific, mark-recapture studies have shown trans-Pacific migrations, but knowledge gaps in migration frequency hinder understanding of regional connectivity and assessments of regional demography for stock assessments. Here, we use oceanographic gradients of stable isotope ratios (i.e., regional isoscapes) to determine exchange rates of blue sharks between the East and West North Pacific Ocean (EPO and WPO). We generated regional δ13C and δ15N distributions for blue sharks from published values in the North Pacific (n = 180; both sexes, juveniles and adults combined). Discriminant analysis suggested low trans-Pacific exchange, categorizing all western (100%) and most eastern (95.3%) blue sharks as resident to their sampling region, with isotopic niche overlap of WPO and EPO highly distinct (0.01–5.6% overlap). Limited trans-Pacific movements suggest that other mechanisms maintain genetic mixing of the North Pacific blue shark population. Potential finer scale movement structure was indicated by isotopic differences in sub-regions of the eastern and western Pacific, though application of mixing models are currently limited by aberrantly low blue shark δ13C values across studies. Our results suggest that blue shark population dynamics may be effectively assessed on a regional basis (i.e., WPO and EPO). We recommend further studies to provide size- and sex-specific movement patterns based on empirical isotopic values with large sample sizes from targeted regions. Strategically applied stable isotope approaches can continue to elucidate migration dynamics of mobile marine predators, complementing traditional approaches to fisheries biology and ecology.

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

scholarly journals Direct observations of basin-wide acidification of the North Pacific Ocean

2010 ◽  
Vol 37 (2) ◽  
pp. n/a-n/a ◽  
Author(s):  
Robert H. Byrne ◽  
Sabine Mecking ◽  
Richard A. Feely ◽  
Xuewu Liu
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
North Pacific Ocean ◽  
The North ◽  
Direct Observations ◽  
The North Pacific
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