Can the territorial use rights in fisheries (TURF) stabilize the landings of a highly variable benthic resource? Reexamining the fishery of Concholepas concholepas in North-Central Chile

The fishery of the muricid gastropod Concholepas concholepas is iconic in the southeast Pacific Ocean, since several studies on the species served as basis for changing from an open access regime to territorial user rights in fisheries (TURFs), in the form of management and exploitation areas for benthic resources. This predatory gastropod can be abundant in exposed rocky shores, yet its landings are highly variable in space and time. A few years after new management was implemented, TURF areas exhibited stabilized landings at the national level. However, we have no clear understanding of the outcomes of this management over time at national level versus individual area level. We estimated landings trends using long-term data (18 years) on landings of C. concholepas in most TURF areas of north-central Chile. These temporal trends were estimated by quantifying the landings slopes for each area and their individual deviations from the population level estimates (overall slope minus individual slope). We found that nearly 20% of areas stopped harvesting in 2010, most areas exhibited declining landings over time, and nearly as many areas exhibited slopes above and below the mean overall slope. The change in the traditional way of fishing, the increase in illegal fishing, and the lack of adequate knowledge about the larval cycle of the species may have driven the failure of the TURF areas for C. concholepas. Since fishing is prohibited in the remaining open access areas but is poorly controlled, we suggest ending this prohibition in open access areas and maintaining existing TURF areas to assess actual landings of C. concholepas in Chile. This change may improve the protection of the species.