Effect of data weighting on the mature male biomass estimate for Alaskan golden king crab

2017 ◽  
Vol 192 ◽  
pp. 103-113 ◽  
Author(s):  
M.S.M. Siddeek ◽  
J. Zheng ◽  
A.E. Punt ◽  
D. Pengilly
1997 ◽  
Vol 54 (5) ◽  
pp. 1121-1134 ◽  
Author(s):  
J Zheng ◽  
M C Murphy ◽  
G H Kruse

A modifiable harvest rate constrained by a minimum spawning abundance (threshold) is currently used to set the annual harvest level for Bristol Bay red king crab, Paralithodes camtschaticus. A length-based simulation model was constructed to evaluate effects of recruitment, natural mortality, and handling mortality on this harvest strategy. Evaluation criteria included mean yield, stability of yield, harvest opportunity, and stability of spawning stock. Optimal mature male harvest rates were strongly negatively related to handling mortality. For any given harvest rate, handling mortality is a key factor influencing optimal thresholds. The current harvest strategy produces a high mean yield and low variability in yield under low handling mortality scenarios, but the population is at high risk of collapse with a high handling mortality. Given uncertainties of recruitment, natural mortality, and handling mortality estimates, we recommend reducing mature male harvest rate from 20 to 15% and maximum legal male harvest rate cap from 60 to 50%. If handling mortality rate is greater than 30%, then we recommend increasing the threshold from 6600 to 11<|>000 metric tons of effective spawning biomass. Our recommended harvest strategy produces a mean yield similar to the current harvest strategy and safeguards against recruitment overfishing.


Author(s):  
S.M. Geyer ◽  
C.L. Mendenhall ◽  
J.T. Hung ◽  
E.L. Cardell ◽  
R.L. Drake ◽  
...  

Thirty-three mature male Holtzman rats were randomly placed in 3 treatment groups: Controls (C); Ethanolics (E); and Wine drinkers (W). The animals were fed synthetic diets (Lieber type) with ethanol or wine substituted isocalorically for carbohydrates in the diet of E and W groups, respectively. W received a volume of wine which provided the same gram quantity of alcohol consumed by E. The animals were sacrificed by decapitation after 6 weeks and the livers processed for quantitative triglycerides (T3), proteins, malic enzyme activity (MEA), light microscopy (LM) and electron microscopy (EM). Morphometric analysis of randomly selected LM and EM micrographs was performed to determine organellar changes in centrilobular (CV) and periportal (PV) regions of the liver. This analysis (Table 1) showed that hepatocytes from E were larger than those in C and W groups. Smooth endoplasmic reticulum decreased in E and increased in W compared to C values.


Author(s):  
Ryo Futamura ◽  
Kentaro Morita ◽  
Koume Araki ◽  
Masato Ayumi ◽  
Shoji Kumikawa ◽  
...  

2021 ◽  
Vol 240 ◽  
pp. 105964
Author(s):  
Cory Lescher ◽  
Noëlle Yochum ◽  
Brad Harris ◽  
Nathan Wolf ◽  
John Gauvin

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