The Biodiversity of Peter I Island-The Most Remote Island in the World

Peter I Island is one of the most isolated and least visited islands on earth; lying within the Antarctic Polar Front but over 420 km from continental Antarctica makes it inherently interesting to study in the context of polar biogeography. First discovered in 1821, it was only landed on in 1929 due to challenging ice conditions. Subsequent landings for scientific exploration have been rare, with the primary focus on geological studies and limited biodiversity assessments. To date, only two dedicated marine biodiversity surveys have been conducted, revealing unexpectedly high diversity but limited taxonomic coverage. We provide a comprehensive species list of the area by compiling all previous records with our own data collected in January 2022. Here, a BioBlitz was conducted on the island and surrounding waters, documenting terrestrial, avian and marine species. We identify 15 species new to the region, including benthic and pelagic fauna, as well as an expanded understanding of cetacean and pinniped presence in the area. Marine SCUBA surveys revealed diverse algal and invertebrate communities, emphasising Peter I Island's unique ecological makeup within the Antarctic marine ecosystem. This study establishes a critical biodiversity baseline for ongoing monitoring as the island faces potential ecological shifts due to global change.