A new model of growth back-calculation incorporating age effect based on otoliths
Morita, K.; Matsuishi, T. (2001). A new model of growth back-calculation incorporating age effect based on otoliths. Can. J. Fish. Aquat. Sci. 58(9): 1805-1811
In: Canadian Journal of Fisheries and Aquatic Sciences = Journal canadien des sciences halieutiques et aquatiques. National Research Council Canada: Ottawa. ISSN 0706-652X; e-ISSN 1205-7533, more
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Keywords |
Dimensions > Size Fauna > Aquatic organisms > Aquatic animals > Fish Musculoskeletal system > Anatomical structures > Skeleton > Exoskeleton > Scales Properties > Physical properties > Weight Salmon Salmon Vertebrates > Fishes > Osteichthyes > Salmoniformes > Salmonidae > Salmon
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Abstract |
We developed a simple back-calculation model that includes the age effect in which otolith size increases continuously during no-growth periods. To evaluate the validity of our proposed model, we back-calculated the past fish lengths and growth rates using the new model and seven traditional back-calculation models (scale-proportional hypothesis (SPH), body-proportional hypothesis (BPH), Fraser-Lee, biological intercept, nonlinear SPH, nonlinear BPH, and modified Fry) using the otoliths of individually tag-recaptured white-spotted char (Salvelinus leucomaenis). The estimated fish lengths corresponded well to observed fish lengths for simple traditional (SPH, BPH, and Fraser-Lee) and the new models. However, the back-calculated growth rates did not correspond to observed growth rates except for the new model. All previous models had considerable bias; growth rates of slow-growing fish were overestimated. As our model incorporating the age effect did not show such bias, this bias would be attributed to the age effect. Our proposed back-calculation model incorporating the age effect should be useful to estimate past growth rates at the individual level. |
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