Abstract

Pristipomoides aquilonaris (wenchman, n = 115) were collected off Louisiana and Florida during October - November 2007 along a depth range of 77 - 192 m. Fish were weighed and measured to the nearest 0.001 kg and 1.0 mm, respectively. Both sagittal otoliths were removed and right otoliths were sectioned using a low speed saw with a diamond wafering blade. Readers used otolith growth increment measurements on various whole and sectioned otoliths from fish of differing sizes to determine average placement of core and growth increments. Each specimen was aged (using increments), and agreement between 2 readers was calculated using: average percent error (3.98%), coefficient of variation (5.62%), index of precision (3.98%), and percent agreement ± 1 band (83.5%) and ± 2 bands (97.4%). Linear and nonlinear regressions were fit to meristic and depth data. Age frequencies demonstrated a large group of individuals with 1 or 2 otolith growth increments. Length frequencies showed more than a third of the collection was 150 - 174 mm fork length (FL). Size-at-age with fork length and whole weight and the von Bertalanffy growth curve all showed similar growth patterns and asymptotic trends. We conclude that more wenchman of various sizes and locations should be collected monthly to improve accuracy in the relationship between age and growth

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