Shallow water foraminifera from Niue and Beveridge Reef (South Pacific): Insights into ecological significance and ecosystem integrity

Abstract

Niue represents one of many important steppingstones facilitating the dispersal of marine organisms across the tropical Pacific Ocean. This study is part of a collaborative expedition involving National Geographic Pristine Seas, the government of Niue, Oceans 5, and the Pacific Community. We present the first survey documenting the species richness of foraminiferal communities in Niue and nearby Beveridge Reef and explore their significance for ecosystem integrity. A substantial portion (59%) of Niue's foraminiferal assemblages is Large Benthic Foraminifera (LBF), a symbiont-bearing group known as ecosystem engineers and indicators of coral reef regime shifts. LBF species reported here reflect the gradual decrease of tropical diversity from the Coral Triangle towards the central Pacific Ocean. Calcarinidae, an LBF family represented in this study by two species, is the easternmost ever recorded in published literature, and the biogeographical dispersal of this temperature-controlled group is of great importance to future global warming related studies. Foraminifera are an important component of beach development in Niue, with a close relationship between source and depositional zones. These essential ecological-sedimentary linkages highlight the importance of habitat conservation not only as a means to safeguard biodiversity, but also for its role in the island's physical framework.