Garrett's reed warbler (Acrocephalus musae), sometimes called Society Islands reed warbler or Forster's reed-warbler was a songbird in the genus Acrocephalus. Formerly placed in the "Old World warbler" assemblage (Sylviidae), it is now in the newly recognized marsh warbler family Acrocephalidae. It was endemic to Raiatea and Huahine in the Society Islands.
It was formerly considered a subspecies of the Tahiti reed warbler.
There are 2 subspecies: