Islands play a crucial role in sustaining marine ecosystems in the Pacific Ocean, according to a new study. The waters surrounding islands are rich in phytoplankton, microscopic organisms that inhabit the upper layers of the oceans and serve as an important food source for larger animals. After studying 35 coral reef islands using satellite imagery and ship-based surveys, researchers concluded that the biomass of phytoplankton around islands was up to 86 percent greater than what is found in other parts of the ocean. The findings appear in the journal Nature Communications.