Abstract

Geo-referenced data of fisheries and oceanographic variables collected between 1970 and 2001 in the Upwelling Ecosystem off Colombia, Caribbean Sea (UECC) were exhaustively gathered, validated and standardised. A total of 14 demersal trawl surveys, 17 bottom long-line surveys, 23 commercial bottom long-line and depth hand line fishing trips recorded onboard by observers, 4 annual catch and effort evaluations of the artisanal fleet and 8 oceanographic cruises were examined. Using a geographic information system, 814 thematic maps were constructed in order to introduce the spatial dimension in fisheries analyses for the 25 dominant fish species of the UECC. Due to its economical and ecological importance an integrated analysis for the lane snapper (Lutjanus synagris) was performed relating fishery and oceanographic variables. A number of patterns were identified: (a) lane snapper showed a broader spatial distribution in upwelling seasons that indicates a seasonal enlargement of its habitat; (b) higher values of abundance indexes tend to be associated with locations near upwelling centers; (c) individual sizes tend to decrease towards the south-western UECC, suggesting a nursery area in that sector; and (d) artisanal fleet uses a variety of fishing gears (gillnet, long-line, hand line and pot) for accessing a wide habitat spectra, so spatial distribution of effort is more widespread in artisanal than in industrial fleet which catches lane snapper as bycatch only in trawlable upper shelf areas.

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