Demographical analysis of the pink ling Genypterus blacodes (Schneider 1801) in the austral demersal fishery: A matrix approach evaluating harvest and non-harvest states

Abstract

In this work we model the population dynamics of Genypterus blacodes of the demersal fishery on Chilean southern-austral region, using stage structured matrices, from a 17-year time-series of annual age-specific female abundances. For the parameterized matrices obtained, we calculated population growth rates with confidence intervals, net reproductive rate, reproductive value, stable stage structure, and we performed a sensitivity analysis. We also generated and analyzed an analogous stage structured matrix model for the same population assuming no harvesting. The main results are (1) a negative growth rate for the observed population data; (2) a positive growth rate for the population without the capture effect which is significantly different from the growth rate of the harvested population; (3) the sensitivity analysis revealed that λ is more sensitive to variations in adult survival in the age class 7-10 years; (4) the observed population exhibits a stable stage structure. © 2008 Elsevier B.V. All rights reserved.