Perspectives on the relationship between otolith growth and the conversion of isotope activity ratios to fish ages

1995 ◽  
Vol 52 (10) ◽  
pp. 2296-2303 ◽  
Author(s):  
Daniel K. Kimura ◽  
Craig R. Kastelle
Keyword(s):  
Growth Model ◽  
Linear Growth ◽  
Age Determination ◽  
Growth Curves ◽  
Otolith Growth ◽  
Daunting Task ◽  
Activity Ratios ◽  
Linear Growth Model ◽  
Isotope Activity Ratios ◽  
The Relationship

Ageing of fish otoliths using radiometric methods is now becoming widely accepted. Using this methodology, one has the choice of extracting otolith cores or modeling otolith mass growth. Modeling otolith growth forgoes the difficult work of extracting cores, but one is left with the nearly equally daunting task of selecting and validating an otolith growth model and deriving the corresponding decay equations. We note that the mathematical aspects of this problem appear to have been satisfactorily resolved. However, problems of interpretation remain, and it is not clear whether practitioners fully appreciate the sensitivity of their results to growth model selection and interpretation. We note that the two-stage linear growth model appears to be generally misapplied in the literature. Also, we present evidence that the process of using otolith growth curves estimated from annular ring counts to validate the method of counting annular rings can constitute circular reasoning. Although tedious work, extracting otolith cores seems the most valid way to avoid some serious problems in radiometric age determination work.

scholarly journals Growth rates of the chokka squid Loligo reynaudii d’Orbigny, 1845 (Cephalopoda: Myopsida: Loliginidae) off South Africa, investigated over two years

2021 ◽  
Vol 29 (3) ◽  
Author(s):  
Collette H. Mwanangombe ◽  
Deon Durholtz ◽  
Dawit Yemane ◽  
Jean Githaiga-Mwicigi ◽  
Warwick H. H. Sauer ◽  
...  
Keyword(s):  
South Africa ◽  
Sexual Dimorphism ◽  
Growth Model ◽  
Growth Rates ◽  
Linear Growth ◽  
Maximum Size ◽  
Mantle Length ◽  
Daily Growth ◽  
Males And Females ◽  
Linear Growth Model

Growth of adult chokka squid Loligo reynaudii d’Orbigny was modelled using mantle length and age data derived from samples collected over two years (2003 and 2004) from a single, large cohort of mature and spawning squid. A total of 588 statoliths were examined (310 males, 278 females) from individuals of 71–425 mm mantle length (ML). The maximum size of chokka squid was 425 mm ML for males and 263 mm ML for females. The Francis Growth Model and Linear Growth model were selected for further analysis from six models considered. Males and females attain similar ages, although mantle length-based daily growth rates ranged from 0.75 to 1.02 (0.88 quantile _50) mm/day for males and 0.32–0.45 (0.38 quantile _50) mm/day for females, explaining the sexual dimorphism apparent in the sizes of individuals of this species.

Development of a non-linear growth model for predicting temporal evolution of Scenedesmus obliquus with varying irradiance

2019 ◽  
Vol 42 (12) ◽  
pp. 2047-2054 ◽  
Author(s):  
Jayati Trivedi ◽  
Jasvinder Singh ◽  
Neeraj Atray ◽  
S. S. Ray ◽  
Deepti Agrawal
Keyword(s):  
Growth Model ◽  
Linear Growth ◽  
Temporal Evolution ◽  
Scenedesmus Obliquus ◽  
Non Linear ◽  
Linear Growth Model

scholarly journals Linear growth model analysis of factors affecting boar semen characteristics in Southern China1

2017 ◽  
Vol 95 (12) ◽  
pp. 5339-5346 ◽  
Author(s):  
C. Wang ◽  
J. L. Li ◽  
H. K. Wei ◽  
Y. F. Zhou ◽  
J. J. Tan ◽  
...  
Keyword(s):  
Growth Model ◽  
Linear Growth ◽  
Model Analysis ◽  
Factors Affecting ◽  
Semen Characteristics ◽  
Boar Semen ◽  
Linear Growth Model

scholarly journals A new proportionality-based back-calculation approach, which employs traditional forms of growth equations, improves estimates of length at age

2017 ◽  
Vol 74 (7) ◽  
pp. 1088-1099 ◽  
Author(s):  
Eloïse C. Ashworth ◽  
S. Alex Hesp ◽  
Norman G. Hall
Keyword(s):  
Cross Validation ◽  
Growth Curves ◽  
Bivariate Distribution ◽  
Regression Equations ◽  
Otolith Growth ◽  
New Approach ◽  
Growth Equations ◽  
Back Calculation ◽  
The Relationship ◽  
Otolith Size

The performance of a new proportionality-based back-calculation approach, describing the relationship among length, otolith size, and age using traditional growth curves and assuming a bivariate distribution of deviations from those curves, was evaluated. Cross-validation was used for six teleost species to compare predictions of expected lengths or otolith sizes at age, given otolith size or length, respectively, with those of other proportionality-based approaches that incorporate age. For four species, and particularly Acanthopagrus butcheri when using a biological intercept, better estimates were produced using the new model than were produced using the regression equations in the other back-calculation approaches. Back-calculated lengths for A. butcheri estimated using this model were more consistent with observed lengths, particularly when employing a biological intercept, than those obtained using other proportionality-based approaches and also a constraint-based approach known to produce reliable estimates. By selecting somatic and otolith growth curves from a suite of alternatives to better describe the relationships among length, otolith size, and age, the new approach is likely to produce more reliable estimates of back-calculated length for other species.

A linear growth model including education

1973 ◽  
Vol 33 (3-4) ◽  
pp. 251-279
Author(s):  
Gerhard O. Orosel
Keyword(s):  
Growth Model ◽  
Linear Growth ◽  
Linear Growth Model

Age determination and growth in wild Petrogale lateralis pearsoni and captive Petrogale lateralis 'MacDonnell Ranges race'

2004 ◽  
Vol 52 (4) ◽  
pp. 447 ◽  
Author(s):  
Michelle Jones ◽  
David Taggart ◽  
Peter Temple-Smith
Keyword(s):  
Growth Rate ◽  
Growth Models ◽  
Age Determination ◽  
Growth Curves ◽  
Tammar Wallaby ◽  
Length Growth ◽  
Non Linear ◽  
In The Wild ◽  
Using Data ◽  
Linear Growth Model

Accurate assessment of age is important for effective captive husbandry techniques and assists in understanding developmental processes, population dynamics, reproductive strategies and seasonal breeding. Using linear and non-linear regression, this study analysed the growth rate of the head and pes length of known-age, captive-born pouch young of the black-footed rock-wallaby, Petrogale lateralis 'MacDonnell Ranges race'. Growth curves for head and pes length from the captive-born pouch young were then used to predict the age of pouch young of P. lateralis pearsoni using data collected from the field. Observations on the development of the eyes, ears and body of P.�lateralis 'MacDonnell Ranges race' were also recorded. Results showed that a non-linear growth model best described the head-length growth of captive-born pouch young (r2 = 99.5%), whereas logistic regression was the most accurate predictor of pes-length growth (r2 = 99.6%). No significant differences were found when the two growth models were applied to head and pes data from wild pouch young, suggesting that the growth models derived from captive animals can be used to accurately predict the age of pouch young in the wild. During a preliminary cross-fostering trial, we examined growth of the head and pes length in pouch young of P. lateralis 'MacDonnell Ranges race' that had been cross-fostered onto the teats of surrogate tammar wallaby (Macropus eugenii) mothers; comparisons were made to the growth rate of pouch young of the same race that had remained with their natural mothers.

scholarly journals Small saving in India with special reference to Saving pattern of weavers in Handloom sector of Bodoland Territorial Area Districts(BTAD), Assam, India

2021 ◽  
Vol 58 (1) ◽  
pp. 2626-2641
Author(s):  
Dr. Konita Basumatary
Keyword(s):  
Marital Status ◽  
Special Reference ◽  
Income Tax ◽  
Linear Growth ◽  
Percent Level ◽  
Secondary Data ◽  
Individual Investor ◽  
Significant Difference ◽  
Linear Growth Model ◽  
The Relationship

Small saving scheme is one of the key investment avenues for individual investor. It encourages small-income investors to invest and earn high returns and to save on income tax as well.  In this paper the growth of small saving from 2001-02 to2017-18 has been analyzed by adopting non linear growth model. The paper also examined factors leading to saving differential of weavers in the handloom sectors of BTAD areas. The study is based on both primary and secondary data. To determine the relationship between various variables multiple regressions has been used. It is found that saving of weaver is positively determined by their monthly wages and negatively by family size and they are found significant at 1 percent level. Again the saving of weavers is found to be negatively determined by dependent children. Saving differences among gender and community is found insignificant, that mean we cannot say whether saving is greater (smaller) for male than female and for STs than non ST. So we cannot find a differences in saving behaviour among gender and community although there's found a significant difference in saving among marital status and types of weaver.  

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