Fisheries Research Articles
A new proportionality-based back-calculation approach, which employs traditional forms of growth equations, improves estimates of length at age
Document Type
Article
Publication Date
12-22-2016
Journal Title
Canadian Journal of Fisheries and Aquatic Sciences
ISSN
Print: 0706-652X Electronic: 1205-7533
Disciplines
Aquaculture and Fisheries | Marine Biology
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.
Recommended Citation
Ashworth, E C,
Hesp, S A,
and
Hall, N G.
(2016), 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).
https://library.dpird.wa.gov.au/fr_fja/174
