Pre-eradication updated seabird survey including new records on Amsterdam Island, southern Indian Ocean

An invasive predator eradication campaign is planned for 2024 on Amsterdam Island, one of world’s top priority island for seabird conservation. In order to monitor the effects on seabird colonies post-eradication, a survey of burrow-nesting species and population monitoring of albatrosses, penguins, skuas and terns was organised pre-eradication. Several counting techniques and acoustic methods were used to infer presence/absence of burrow-nesting species and to estimate abundance of other species, as well as genetic methods for species identification. In total 14 breeding (or probably breeding) seabird species were detected on Amsterdam Island, among which eight burrowing petrels including two species never described on the island: the Juan Fernandez petrel Pterodroma externa and the sooty sherwater Ardenna grisea. Based on these new data, the introduced mammal eradication campaign on Amsterdam, if successful, will likely be extremely beneficial for seabird conservation, and may also favor the colonization of Amsterdam by new seabird species.