Age validation of the northern stock of black sea bass (Centropristis striata) in the Atlantic Ocean

Issue:

Author(s): 
Elise R. Koob, Scott P. Elzey, John W. Mandelman, and Michael P. Armstrong
Cover date: 
2021
doi: 
10.7755/FB.119.4.6
Pages: 
261-273
Published online 17 November 2021
Abstract: 

Inaccurate age determinations can have serious effects on age-structured stock assessments that are used to manage fish populations. A recent push toward using an age-based model for the northern stock of black sea bass (Centropristis striata) led to an increase in direct aging effort in the northeastern United States. Yet, no large-scale otolith age validation study for this stock exists. We examined the annual periodicity of otolith growth in this species through marginal increment analysis with otoliths of fish from 3 age groups (fish of ages 1–2, ages 3–4, and ages 5+) and from 2 regions, north and south of the Hudson Canyon. Additionally, we validated the assignment of the first annulus through modal length–frequency analysis of young-of-the-year fish. The marginal increment ratio differed between age groups throughout the year, supporting the separation of these samples for age validation purposes. Higher ratios were observed in black sea bass from the region south of the Hudson Canyon throughout most of the year; however, fish from north of the canyon appear to accrete more otolith material during winter. Annual growth increments were deposited once per year, in spring or early summer, for all fish. In addition, absolute age was validated for the first time for this stock.