In September 2022, a collaborative expedition across Samoa’s main islands of Upolu and Savai’i delivered one of the most comprehensive national assessments of coral reef health to date. Led by Samoa’s Ministry of Natural Resources and Environment and Ministry of Agriculture and Fisheries, in partnership with the Waitt Institute and Conservation International, the survey returned encouraging signs of recovery, particularly on the reefs of Upolu.

Key findings include:

• Coral cover increased on Upolu since 2017, showing signs of recovery from past bleaching events.

• Savai’i supported greater coral diversity, despite having lower overall coral cover.

• Fish biomass was higher on Upolu, indicating the presence of larger fish species, while Savai’i showed a decline in both fish density and biomass since 2017.

• Macroinvertebrate densities remained low across both islands, raising concerns over the impacts of overharvesting.

• δ15N analysis suggests land-based pollution may be concentrated near Apia, although more lagoon-based surveys are needed for definitive conclusions.

The expedition also supports the Samoa Ocean Strategy, feeding directly into marine spatial planning and coastal management efforts. With over 70% of Samoa’s population living within 1 km of the coast, the results underscore the urgency for community-based fisheries management and water quality improvements to safeguard reef resilience.