Temporal Patterns in the Diversity and Structure of Macrobenthic Assemblages Associated With Intertidal Beds of the Exploited Macroalga Chondracanthus chamissoi

ABSTRACT

In recent decades, the demand for red macroalgal species has increased dramatically, leading to intensified harvesting pressure and perturbation on populations and the habitat they provide for associated assemblages. Chondracanthus chamissoi (C. Agardh) Kützing is the most harvested and economically valuable red macroalgal species along the temperate SE Pacific coastline, where it forms important habitat for associated organisms. However, the diversity and structure of assemblages associated with intertidal C. chamissoi habitats, and the likely drivers of ecological patterns, are poorly understood. This study aimed to examine the annual and seasonal variation in the structure of assemblages inhabiting an extensive natural bed of C. chamissoi in northern Peru. We sampled macrofauna and flora on an intertidal mixed‐substrata beach each month, from February 2018 to December 2022, and explored links between assemblage structure and putative environmental drivers. We recorded pronounced seasonal variability in the structure of intertidal macrobenthic assemblages, driven by fluctuations in a few key species, including Asterfilopsis furcellata , Semimytilus patagonicus and Tegula spp. Predictor variables, which included sea surface temperature and harvesting intensity, explained ~47% of the observed variability in total community biomass. Long‐term ecological information is needed to improve our understanding of natural beds of C. chamissoi and to support conservation and management initiatives for this exploited ecosystem and its associated biodiversity. Continued and expanded monitoring of these habitats in northern Peru is needed in the face of a growing artisanal fishery for C. chamissoi and other concurrent stressors.