Frequency of Increment Formation on Sagittae of North Pacific Albacore (Thunnus alalunga)

1985 ◽  
Vol 42 (9) ◽  
pp. 1552-1555 ◽  
Author(s):  
R. M. Laurs ◽  
R. Nishimoto ◽  
J. A. Wetherall
Keyword(s):  
North Pacific ◽  
Average Rate ◽  
Commercial Fisheries ◽  
Systematic Bias ◽  
Otolith Growth ◽  
The North ◽  
Daily Increments ◽  
Increment Formation ◽  
Thunnus Alalunga ◽  
The North Pacific

An examination of sagittae from 116 albacore (Thunnus alalunga) caught in the North Pacific, injected with tetracycline, tagged, released, and subsequently recaptured in sport and commercial fisheries showed that detectable increments are formed on these otoliths at an average rate of 0.954 per day. We take this as a confirmation of daily increment formation in North Pacific albacore sagittae. The slight departure of observed mean increment counts from the expected rate of one per day may be due to an occasional interruption of otolith growth, or to a systematic bias in detecting daily increments or interpreting otolith microstructure. The estimated rate of detectable increment formation applies explicitly to albacore of fork lengths between about 50 and 100 cm. If the same rate holds for fish smaller than 50 cm, as is likely, most albacore taken in sport or commercial catches can be aged accurately by applying our methods and expanding the increment count by 5%.

Age and growth of albacore Thunnus alalunga in the North Pacific Ocean

2012 ◽  
Vol 80 (6) ◽  
pp. 2328-2344 ◽  
Author(s):  
K.-S. Chen ◽  
T. Shimose ◽  
T. Tanabe ◽  
C.-Y. Chen ◽  
C.-C. Hsu
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Age And Growth ◽  
The North ◽  
Thunnus Alalunga ◽  
The North Pacific

Transoceanic migration rates of young North Pacific albacore, Thunnus alalunga, from conventional tagging data

2008 ◽  
Vol 65 (8) ◽  
pp. 1681-1691 ◽  
Author(s):  
Momoko Ichinokawa ◽  
Atilio L. Coan, ◽  
Yukio Takeuchi
Keyword(s):  
North Pacific ◽  
Seasonal Migration ◽  
Western Pacific ◽  
Migration Routes ◽  
Migration Rates ◽  
The North ◽  
Maximum Likelihood Methods ◽  
Westward Movement ◽  
Thunnus Alalunga ◽  
The North Pacific

This study summarizes US and Japanese historical North Pacific albacore ( Thunnus alalunga) tagging data and uses maximum likelihood methods to estimate seasonal migration rates of young North Pacific albacore. Previous studies related to North Pacific albacore migration have found that the frequency of albacore migrations is difficult to quantify because of inadequate amounts of tags released by the US tagging program in the western Pacific. Use of the combined Japan and US tagging data solves this problem. This study also incorporates specific seasonal migration routes, hypothesized in past qualitative analyses, to avoid overparameterization problems. The estimated migration patterns qualitatively correspond to those from previous studies and suggest the possibility of frequent westward movements and infrequent eastward movements in the North Pacific. This frequent westward movement of young albacore in the North Pacific would correspond to a part of albacore life history in which immature fish recruit into fisheries in the western and eastern Pacific and then gradually move near to their spawning grounds in the central and western Pacific before maturing.

scholarly journals Characteristics of the North Pacific Oscillation in CMIP5 Models in Relation to Atmospheric Mean States

2020 ◽  
Vol 33 (9) ◽  
pp. 3809-3825
Author(s):  
Mi-Kyung Sung ◽  
Changhyun Yoo ◽  
Sang-Wook Yeh ◽  
Yu Kosaka ◽  
Soon-Il An
Keyword(s):  
North Pacific ◽  
Climate Models ◽  
Horizontal Wind ◽  
Cmip5 Models ◽  
Systematic Bias ◽  
North Pacific Oscillation ◽  
The West ◽  
The North ◽  
The Mean ◽  
The North Pacific

AbstractThe North Pacific Oscillation (NPO), the second leading atmospheric mode in the North Pacific Ocean, is known to be responsible for climate variability and extremes in adjacent regions. The reproducibility of the NPO in climate models is thus a topic of interest for the more accurate prediction of climate extremes. By investigating the spatial characteristics of the NPO in models from phase 5 of the Coupled Model Intercomparison Project (CMIP5), this study reveals the intimate relationship between the NPO structure and the atmospheric mean states over the North Pacific. The majority of the models reasonably capture the meridional contrast of pressure anomalies, but the detailed horizontal characteristics of the NPO are found to differ among the models. Diagnostic analysis of 30 climate models and long-term observations suggest that systematic bias in the mean atmospheric baroclinicity over the North Pacific crucially affects the horizontal shape and zonal position of the NPO. In the models in which the climatological continental trough over the western North Pacific extends farther to the east, the NPO tends to be simulated farther to the east, strengthening its impact on the downstream climate. In contrast, when the climatological continental trough is reduced in size toward the west, the growth of the NPO is limited to the west, and its influence is weakened downstream. This relationship can be understood via the altered available potential and kinetic energy conversions that feed the total energy of the NPO, primarily stemming from the difference in the mean horizontal temperature gradient and stretching deformation of the mean horizontal wind.

Intra-seasonal and inter-annual patterns in the demographics of sand lance and response to environmental drivers in the North Pacific

2019 ◽  
Vol 617-618 ◽  
pp. 221-244 ◽  
Author(s):  
MR Baker ◽  
ME Matta ◽  
M Beaulieu ◽  
N Paris ◽  
S Huber ◽  
...  
Keyword(s):  
North Pacific ◽  
Environmental Drivers ◽  
Sand Lance ◽  
The North ◽  
The North Pacific ◽  
Annual Patterns
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