Deep anthropogenic impacts on benthic marine diversity of the Humboldt Current Marine Ecosystem: Insights from a Quaternary fossil baseline

• DOI: 10.3389/fmars.2022.948580
• Publication Date: 2022-09-14T14:19:57Z
• Authors: Marcelo M. Rivade...; Sven N. Nielsen
• Keywords: Marine ecosystem; Dominance (genetics); Marine protected area; Overfishing

The Humboldt Current Marine Ecosystem (HCE) is one of the most productive areas in global ocean, but current anthropogenic stressors, particularly overfishing, pose a significant threat to marine biodiversity. Moreover, limited time scale modern assessments may underestimate magnitude human alterations Here we use rich Quaternary fossil record present along HCE coast, encompassing last ca. 500 kyr, build baseline evaluate impact activities on diversity mollusk assemblages. We compiled an extensive database >13,000 occurrences and 370,000 individuals 164 species gastropods bivalves from fossiliferous outcrops southern Peru northern Chile (15-30°S). tested for changes coverage-based richness, dominance, composition (Chao dissimilarity, unweighted weighted by abundance), relative abundance (i.e., proportion individuals) exploited artisanal fisheries. Comparisons between assemblages were carried out at different scales spatial aggregation buffer against inherent differences temporal averaging. Species shows remarkable stability assemblages, Middle Pleistocene Holocene, aggregation. Modern showed drastic compared counterparts when analyses considered scales, i.e., composition, 3 6-fold reduction species, not richness dominance. Results suggest that contemporaneous disrupted long-term composition. unseen past kyr seems deeply perturbated overfishing. Our synthesis sets foundations conservation paleobiology approach robustly understand impacts stressors HCE.