The last wild Guam Rail was killed by the accidentally introduced Brown Tree Snake (Boiga irregularis) in 1987.
Notes on verification
Multiple independent, reputable sources (BirdLife International, NRDC, peer-reviewed ecological literature) confirm the Guam Rail's extinction in the wild by 1987 due to predation by the introduced brown tree snake. The exact phrasing 'last individual killed' is a simplification of a population collapse, but the core facts are well corroborated.
Sources
- Species recoveries bring hope amidst the biodiversity crisis (iucn.org)
- https://www.birdlife.org/news/2020/01/20/how-did-the-guam-rail-come-back-from-extinction-in-the-wild/ (birdlife.org)
- https://www.researchgate.net/publication/227677156_Impacts_of_the_brown_tree_snake_patterns_of_decline_and_species_persistence_in_Guam%27s_avifauna (researchgate.net)
- https://a-z-animals.com/articles/how-one-invasive-species-is-rewiring-an-entire-islands-ecosystem/ (a-z-animals.com)
- https://www.nrdc.org/stories/guam-rails-are-no-longer-extinct-wild-something-only-one-other-bird-can-claim (nrdc.org)