Analysis of sportfishing catch rates of striped marlin (Tetrapturus audax) at Cabo San Lucas, Baja California Sur, Mexico, and their relation to sea surface temperature

Abstract

Cabo San Lucas, Baja California Sur, Mexico, is the main sportfishing location for striped marlin, with a mean annual catch rate of 0.6 fish per fishing trip. In the present study, the interannual and seasonal variation of sportfishing catch rates from 1990 to 1999, and their relationship to mean monthly sea surface temperatures were analysed. Although interannual variation was not significant, the seasonal effect showed significant differences, with highest average catch rates in winter, and lowest catch rates in summer (0.9 and 0.3 respectively). An interannual significant difference with a decreasing tendency was in length analysis. Significant length and weight differences were found between males and females. Among females, the heaviest fish were recorded during spring. A significant relationship between catch rate and sea surface temperature (r = –0.62) was found, but no significant changes of catch rates could be measured during the 1992–1993 and 1997–1998 El Niño Southern Oscillation events, in spite of an apparent catch rate increase during the spring of 1998. Highest catch rates were recorded at between 22 and 24°C.