" We estimated annually-averaged sea surface temperatura (SST) anomalies for four 2 x 2 quadrants in the Gulf of California, Mexico using ICOADS (International Comprehensive Ocean-Atmosphere Data Set) and ERSST (NOAA Extended Reconstructed SST) data. We compared the anomalies to large-scale environmental indices (Pacific Decadal Oscillation index, PDO; and Nino 3 index, N3). Hamming filters were used to isolate high (< 10 years), decadal (10–20 years) and low (> 20 years) frequencies for comparison. The relationships between the decadal-scale variations and the relative abundance of stocks being harvested by two important fisheries (penaeid shrimps and California sardine, Sardinops sagax) were explored. We found that sardine relative abundance coincides well with estimated SST, increasing during the cooling intervals and declining through the warming periods, as expected given the Gulf of California is the southernmost limit of its distribution. Shrimp abundance appears to increase during warming intervals with a three-year lag which remains unexplained."