Implementation of seed collection programs for the recovery of Argopecten purpuratus populations in the La Rinconada marine reserve (Antofagasta, Chile)

Abstract

Abstract ‘La Rinconada Marine’ Reserve (MR), Chile was created in 1997 to preserve the genetic stock of the scallop Argopecten purpuratus and eventually to supply seed to areas outside of the reserve and support aquaculture activities. Data from biological and fisheries monitoring of A. purpuratus as well as environmental conditions in the MR are available for the period from 1993 to 2009. The continuous extraction of A. purpuratus from La Rinconada MR in Chile, without a science‐based exploitation plan, has not only decreased the abundance and population structure of the species but has also significantly affected seed settlement in artificial collectors and population recruitment. Therefore, the goals of the MR have not been achieved. This review of biological and fishing studies of A. purpuratus in La Rinconada MR provides a basis for the implementation of a sustainable programme for the natural collection of A. purpuratus seed for population recovery. A. purpuratus recruitment varies substantially between years and is not strongly related to the size of the parental population. Larval collection and recruitment depend on environmental events (El Niño‐Southern Oscillation) and biological substrate availability (Rhodymenia red algae). These factors produce a bentho‐pelagic decoupling between parental abundance, larval production and subsequent recruitment of A. purpuratus that limits stock recovery in the MR. To address the poor population status of A. purpuratus in the MR, recovery of the adult population is needed. Therefore, an assisted collection and recruitment strategy is proposed to increase the population and enable the generation of surplus seed, fulfilling the initial aims of La Rinconada MR.