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Abstract
We compared whole and sectioned otoliths, scales, dorsal spine sections, opercular bones, and vertebrae for aging bluefish Pomatomus saltatrix from the Chesapeake Bay region. Opercular bones and vertebrae were unusable; they were spongy and pitted, and contained no visible marks. The remaining structures exhibited concentric rings that were interpreted as annual marks; however, structures differed greatly in mark clarity. Over the age range 1-14 years, sectioned otoliths were the best structure, consistently showing the clearest marks, highest confidence scores, and highest within- and between-reader agreement. Whole otoliths were the second best structure, providing the second highest overall within-reader agreement and 95% agreement with sectioned otoliths to age 4. Scales were inferior to sectioned and whole otoliths, especially after age 4, when within-reader agreement was only 33% and agreement with sectioned otoliths was only 26%. Dorsal spine sections were undesirable for aging bluefish, providing the lowest reader agreement and exhibiting unclear, inconsistent marks.
