Latin american journal of aquatic research
versión On-line ISSN 0718-560X
GATICA, Claudio et al. Relationship between the West Wind Drift and swordfish (Xiphias gladius) relative abundance off Chile. Lat. Am. J. Aquat. Res. [online]. 2009, vol.37, n.1, pp. 97-105. ISSN 0718-560X.
The relationship between the relative abundance of swordfísh (Xiphias gladius) off the Chilean coast and the latitudinal location of the West Wind Drift (WWD) was analyzed from a macro scale standpoint for the period between 1989 and 1996. The position of the axis of the eastern boundary of the WWD was estimated by determining the latitude of the bifurcation of the isotherms obtained from the average monthly sea surface temperatures. The capture per unit effort (CPUE) of the small-scale driftnet fleet was used as a relative abundance Índex for the resource. The WWD and CPUE time series were analyzed on a monthly scale with different lags between the series. Two methodological approaches were used to determine the relationship between these two time series. The first was the methodology proposed by Pyper & Peterman (1998), which was used to correct the actual degrees of freedom in the cross-correlation test. The second approach consisted in analyzing the correlation of two stationary time series at different lags. Those approaches indicated a significant relationship between the latitudinal location of the WWD and the CPUE on a monthly scale. The relationship found between the WWD and the swordfish relative abundance suggests that the WWD could be a macro scale indicator of oceanographic and meteorological variabihty that could affect swordfish distribution patterns and availability.
Palabras clave : swordfish; XipMas gladius; distribution; West Wind Drift; Chile; southeastern Pacific.