Guam Reed-warbler

The Guam Reed-warbler (<em>Acrocephalus luscinius</em>) was a member of the family Acrocephalidae that has been classified as Extinct by the IUCN, representing one of the many endemic Pacific island birds lost following the introduction of the brown tree snake to Guam after World War II. Detailed plumage and behavioral descriptions of this species are limited in the available literature. When extant, it inhabited forest, grassland, and wetland environments across Guam in the western Pacific. Its geographic range was confined to the island of Guam, and like many island reed-warblers it was likely an insectivore. Nesting involved cup-nest construction, and the recorded clutch size of 2 to 4 eggs suggests relatively typical reproductive output for the genus. Incubation and fledging periods and song information are not documented in available records. The extinction of the Guam Reed-warbler is emblematic of the devastating ecological impact that introduced predators can have on island vertebrates with no evolutionary experience of terrestrial predation, serving as a cautionary example for island conservation worldwide.