Seasonal changes in the distribution and concentration of jumbo flying squid (Dosidicus gigas) off the Peruvian coast were assessed using catch and effort data from the jigging vessels that worked within the area between 1991 and 1999. The results showed a wide distribution of D. gigas along the coast, the highest concentrations occurred along the coast of northern Peru, from Puerto Pizarro (3°24′S) to Chimbote (9°S), with low to medium concentrations observed off Pisco (13°42′S) and Atico (16°14′S). The highest catch per unit effort (CPUE) values occurred during autumn, winter and spring with the squid tending to disperse in summer. There is some evidence of interannual differences associated with changes in sea surface temperature. Catches, fishing effort and CPUE were the highest between 1991 and 1995 and lowest in 1996. © 2001 Published by Elsevier Science B.V.