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

Ashworth, E.C., Hesp, S.A. and Hall, N.G. (2017) A new proportionality-based back-calculation approach, which employs traditional forms of growth equations, improves estimates of length at age. Canadian Journal of Fisheries and Aquatic Sciences, 74 (7). pp. 1088-1099.

Link to Published Version: https://doi.org/10.1139/cjfas-2016-0409
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Abstract

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.

Publication Type: Journal Article
Murdoch Affiliation: School of Veterinary and Life Sciences
Centre for Fish and Fisheries Research
Publisher: National Research Council of Canada
Copyright: © 2017 Canadian Science Publishing. All rights reserved.
URI: http://researchrepository.murdoch.edu.au/id/eprint/37594
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