Globally, introductions of non-indigenous species have caused dramatic economic and ecological damage. Most research on marine invasions has occurred in locations easily accessible by researchers, but much less is known about introductions to remote islands. In the central Pacific, Palmyra Atoll represents one of the last remaining quasi-pristine reef systems left in the world. In the 1940s the Atoll underwent extensive military modifications, potentially making it susceptible to invasive species. Here we describe the presence of five non-indigenous invertebrate and algal introductions at Palmyra, including two sponges, Haliclona (Sigmadocia) caerulea and Gelliodes fibrosa; one bryozoan; Zoobotryon verticillatum; one hydroid, Pennaria disticha and one macroalga, Acanthophora spicifera. The Hawaiian Archipelago is the most likely source of the introductions via shipping or yachting activity to the Atoll. Currently, the impacts of these introductions remain unknown although future monitoring will assess the influence of these non-indigenous species on this remote reef system.
