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Email the author (Login required) Catch rate standardization for the fishery of royal red shrimp “gamba” (Haliporoides diomedeae) off the coast of central Chile, 2002-2008
DOI: https://doi.org/10.3856/vol38-issue1-fulltext-13
Abstract
The royal red shrimp (Haliporoides diomedeae) is a penaeidea crustacean specie which is caught as target specie since 2002 by the crustacean trawl fishery operating on the central zone off Chile (32º10’S-36º00’S). Catch rates of the royal red shrimp were standardized using Generalized Linear Models (GLM). Preliminary analysis on goodness-of-fit indicates that Gamma distribution was the most adequate to model catch rates as response variable on this specie. The dataset was obtained from logbooks of the commercial fishing trawl between 2002 and 2008. The proposed model explained 18% of the total deviance, and temporal and spatial factors included (year, months, area and depth), were highly significant (p < 0.01). Since 2005, the catch rate shows an increment on their values as a consequence of a decrease in fishing effort. Catch rates also show monthly variations, with higher values during spring-summer 53 kg per trawl hour (kg ha-1) and lower in winter, with 40 kg ha-1. At spatial scale, the standardized catch rates show higher values for those hauls carried out over 500 m of depth and between 33º53’S-34º41’S. The current analysis produces a standardized catch rate time series for the royal red shrimp fishery. This time series can be used as an abundance index to calibrate stock assessment models. The results were discussed on the context of how biological and fishery processes might explain temporal and spatial variability of the standardized catch rates for this resource.
