Seabird Surveys of Aleipata Samoa Offshore Islands

Funding from the Birds New Zealand Pacific Islands Bird Conservation and Research Fund was used to support seabird surveys and monitoring training for staff from the Ministry of National Resources and Environment and the Samoa Conservation Society. The Secretariat for the Pacific Regional Environment Programme and the Northern New Zealand Seabird Trust provided this training.

The islands are rich in biodiversity and both marine and terrestrial ecosystems support significant populations of seabirds; They are the most important islands for red-footed (Sula sula) and brown boobies/Fua’ö (S. leucogaster) and greater frigate birds/Atafa (Fregata minor) in Samoa. They host two species of fruit bats, coconut crabs and marine turtles including the most important nesting sites for hawksbill turtle (Eretmochelys inbricata) in Samoa.

The islands also support populations of a species of threatened terrestrial bird – the friendly ground dove/Tu’aimeo (Gallicolumba stairi), IUCN threat ranking Vulnerable. The Critically Endangered manumea (Didunculus strigirostris) has been recorded there in the past.

During 2022 and 2023 visits to the two islands of Nu’ulua and Nu’utele were conducted. One of these islands is rat/pig free Nu’ulua while Nu’utele  still had rats and pigs. In addition to visual count surveys and burrow searches, song meters were left on the islands to detect procellariid petrels.

During the survey period, Tahiti petrel (Pseudobulweria rostrata) ranked by the IUCN as Near Threatened, and tropical shearwater (Puffinus dichrous) have been confirmed as likely breeding on Upolu, the island where the main town of Apia is situated. The presence of a wide range of predators as well as habitat modification suggests that these seabirds are likely to be in decline.

Visual surveys confirmed seven breeding diurnal seabird species as well as tropical shearwater present in small numbers based on calls heard on song meters. The continued presence of tropical shearwaters on Nu’utele despite presence of rats and pigs is particularly welcome as it is likely recovery would be rapid following eradication of rats and pigs. Eradication of rats and pigs is currently underway supported by Island Conservation through the NZMFAT funded PRISMSS Restoring Island Resilience project through SPREP. 

These two islands are important refuges for seabirds and other fauna and have great potential in terms of restoration. This is particularly so as control of predators on the main islands of Samoa is very limited hampered by vast forested mountainous areas which make access very difficult (note there are no helicopters in Samoa) and funding. Finding remnant populations of procellarid seabirds and protecting them on the main islands is a priority. Use of passive sounds attraction on the island of Nu’utele to attract other procellariid species should also be considered.

Read the final report of the Seabird Surveys of Aleipata here

Find out more about the Birds New Zealand Pacific Islands Bird Conservation and Research Fund here