Some biological aspects of blue marlin (Makaira nigricans) in the recreational fishery at Cabo San Lucas, Baja California Sur, Mexico

The objectives of this study were to analyze intra- and interannual variation in blue marlin Makaira nigricans (Lacépède, 1802) catch rates and to determine size-frequency distributions, length-weight relationship, and condition factor. The information was recorded from 1990-2002 in the recreational fishery at Cabo San Lucas, Baja California Sur (B.C.S.) by the monitoring program of the Centre Regional de Investigacion Pesquera at La Paz, B.C.S. Biological data (eye-fork length, weight, sex, and gonadal maturation stage) were recorded on three consecutive days each month from fish landed by recreational vessels (n = 1017 blue marlin). A significant positive correlation between catch rate and sea surface temperature was found (r = 0.71), which confirmed the preference of this species for warm sea surface temperatures (> 26°C). There was significant interannual variation in eye-fork length, with the maximum in 1996 and the minimum in 2002. The large majority (97%) of the landed fish were female, and most were in maturity stage II (pre-mature), indicating that no reproductive activity is present in this area.