Marine extinctions and their drivers

Abstract

A literature review was conducted to investigate marine global and local extinctions and their drivers; the review followed the PRISMA-EcoEvo guidelines. The data extracted was enhanced with status assessments from the IUCN Red List. We recorded local extinctions for 717 species, of which 18 were global extinctions. Most of these extinctions were recorded on very localized and sub-ecoregion scales. The taxonomic group with the most reported local extinctions was molluscs (31%), followed by cnidarians (22%), fish (17%) and macroalgae (15%). The dominant drivers of extinction differed by taxonomic group. High mobility taxa were driven extinct mainly by overexploitation, whereas low mobility taxa from pollution, climate change and habitat destruction. Most of these extinctions were recorded in the Temperate Northern Atlantic (41%) and the Central Indo-Pacific (30%). Overexploitation was historically the primary driver of marine local extinctions. However, in the last three decades, other drivers, such as climate change, climate variability, and pollution, have prevailed in the published literature. Half of the reported extinctions were of species not assessed by the IUCN Red List, and 16% were species in threatened categories. Global extinctions in the marine environment were mainly attributed to overexploitation, followed by invasive species, habitat destruction, trophic cascades, and pollution. Most extinctions reported in the literature were derived from low-confidence data. Inadequate monitoring may lead to false reports of extinctions or silent extinctions that are never reported. Improved conservation and restoration actions are urgently needed to halt biodiversity loss.