Fauna inhabiting holdfast of Lessonia nigrescens. Is it an indicator of ecological integrity in exploited kelp beds in northern Chile

Abstract

The holdfast of kelp Lessonia nigrescens are habitats for a high diversity of invertebrates. This fauna inhabiting holdfast is sensitive to kelp fishery in northern Chile because among management actions are recommended to harvest the complete plant. The above, and given the ecological role played by brown algae as foundation species, this study proposes the use of the fauna inhabiting holdfast as an indicator for monitoring the ecological integrity of exploited kelp beds. In order to achieve this goal was evaluated the composition, abundance and community structure in the L. nigrescens holdfast in three types of spatially explicit fisheries management: open access areas and management areas (with harvesting), and marine protected areas (without harvesting) in Atacama and Coquimbo (26-32°S). The results show that the fauna inhabiting holdfast in open access areas have lower biodiversity than their counterparts from management areas or marine protected areas. In addition, the structure of communities in holdfast is more variable in open access areas. The results suggested that the kelp holdfast are representative microecosystems of intertidal environments and can be used as sampling units, replicated and comparable for monitoring the ecological integrity of kelp beds in areas of open access to fishery. This ecological indicator is easy to evaluate and disseminate among the users of the kelp production chain.