i
Physicochemical mechanisms of FT-NIRS age prediction in fish otoliths
-
2022
-
Source: Marine and Freshwater Research, 73(6), 846-865
Details:
-
Journal Title:Marine and Freshwater Research
-
Personal Author:
-
NOAA Program & Office:
-
Description:Context. Fourier transform near-infrared spectroscopy (FT-NIRS) is of interest to fisheries managers for rapid age prediction in fish otoliths, yet the underlying prediction mechanism is unknown. Aims. To better understand drivers of FT-NIRS age prediction, we evaluated FT-NIRS spectra and age prediction models for otoliths of red snapper, Lutjanus campechanus, related to otolith structure, mass, and constituents (calcium carbonate (CaCO3) and protein). Methods. Spectra were collected from a set of whole otoliths (n = 84, 0–28 years) and again sequentially after grinding to powder and subsampling a fixed mass of each ground otolith. Protein content was also measured (n = 26) and related to spectra. Key results. Age prediction was diminished in ground and fixed-mass otolith models, but remained within 2 years of traditional ages. Protein content (0.43–0.92% weight) increased significantly with age, implying a concomitant decrease in CaCO3 content. FT-NIRS models predicted protein content to within 0.04%, but protein variability hindered modelling. Spectral characteristics of both CaCO3 and protein are evident in otolith spectra and are implicated in age-prediction models. Conclusions. Changes in otolith composition, mass, and structure underlie FT-NIRS age prediction, but compositional changes inform the majority of age prediction. Implications. These results provide a foundation for understanding FT-NIRS age prediction.
-
Keywords:
-
Source:Marine and Freshwater Research, 73(6), 846-865
-
DOI:
-
Document Type:
-
Rights Information:Other
-
Compliance:Submitted
-
Main Document Checksum:
-
Download URL:
-
File Type: