The fringing reef off Ofu's southern coast is among the healthiest coral ecosystems in the US-administered Pacific. Surveys have consistently recorded unusually high coral coverage and diversity, and the reef has shown a remarkable ability to recover from bleaching events that have damaged comparable systems elsewhere. Scientists from several institutions have studied it extensively, trying to understand what makes it resilient.
For a snorkeler, the practical result is a reef that looks the way reefs used to look before decades of warming and human pressure: dense, colorful, and full of life. The lagoon is shallow enough to access from the beach, the visibility is typically excellent, and the range of species — fish, invertebrates, coral varieties — is impressive for a place so small and remote. Enter via the sandy channels rather than walking on coral heads, and follow any guidance from NPS staff about current conditions. The reef is what makes the trip to Ofu worthwhile.