Variability in the Growth Patterns of Loxechinus Albus Along a Bathymetric Gradient Associated with a Fishing Ground

Here we assess the growth pattern variability of the urchin Lochechinus albus (Molina, 1782) in a fishing ground where it was distributed between 0 and 100 m depth. The bathymetric gradient was divided into four strata, and urchin samples were collected for growth estimations. Images were used to characterize the urchin population along this bathymetric gradient, and historical records for the urchin fishery at this fishing ground were examined. four algorithms were used to model growth, and the Akaike's Information Criteria was used to determine the best model fit. Among the four bathymetric strata, both size and age composition, and the growth patterns of L. albus differed significantly. In the shallowest stratum, urchins were smaller and younger than in the deeper strata. Urchins from 5 to 15 m depth displayed greater initial growth rates compared with urchins from 25 to 100 m depth; however, growth decelerated faster at 5-15 m depth than at deeper habitats. Based on results, we hypothesize that the growth pattern of L. albus observed in the shallowest stratum represents a case of age (size) truncation due to fishing, which requires further study.