Additional records of Christmas Frigatebird Fregata andrewsi in the Northern Territory, Australia

The Christmas Frigatebird Fregata andrewsi is the rarest of five species in the family Fregatidae and is known to breed only on Christmas Island in the eastern Indian Ocean. The number of breeding pairs has declined dramatically over the past 100 years and the species is considered Critically Endangered. Although non-breeding Christmas Frigatebirds range widely throughout south-eastern Asia and the Indian Ocean, there are only two previously confirmed records from mainland Australia. Here we document the occurrence of an adult female Christmas Frigatebird from the Darwin coastline, Northern Territory, on 6 February 2014. Additionally, we document the occurrence of a likely first-year Christmas Frigatebird along the same stretch of coastline on 15 March 2014. We suggest that cyclonic activity and a strong monsoonal trough may have resulted in the arrival of these individuals to mainland Australia.