Significance of marine protected areas in central Chile as seeding grounds for the gastropod Concholepas concholepas

Abstract

The importance of non-harvested areas, marine protected areas, and management and exploitation areas (= harvest-controlled) as seeding areas of Concholepas concholepas (Bruguière, 1789) larvae was quantitatively evaluated at intertidal and subtidal sites at Las Cruces, central Chile. Egg capsules of C. concholepas were sampled along both intertidal and subtidal strip-transects monthly in harvested, harvest-controlled and non-harvested areas from September 1990 to December 1993. Additionally, egg capsules of C. concholepas were sampled at subtidal sites in the 3 categories of areas during 1993 and 1994. Spawning activity of C. concholepas was consistently concentrated between February and July in both the intertidal and the subtidal zones. The total area occupied by egg capsules of C. concholepas was larger in non-harvested than in harvested areas; moreover, larger capsules were found in non-harvested areas. These differences in total surface occupied by egg capsules and their sizes have an important impact on the estimated number of C. concholepas larvae that would be released from harvested and non-harvested areas. We conclude that protected areas may play an important role in the natural replenishment of C. concholepas stocks.