Samoan Islands with black sand beaches. The highest peak is Mt. Silisili, on the island of Savai'i, one of the highest peaks in Polynesia at . The highest point in American Samoa is on Ta’u, Lata Mountain, at . The two large islands of Upolu and Savai'i in Samoa, are among the largest of Polynesian islands, at and , respectively, exceeded in size only by the two main islands of Fiji and the Hawaiian islands of Hawaiʻi and Maui. The island of Upolu is more populated than Savai'i. The next largest island is Tutuila, where the city and harbor Pago Pago (population
Northwestern Hawaiian Islands introduced to Laysan and Lisianksi, where they multiplied and devoured most of the vegetation, permanently extinguishing several species. However, most of the damage was reversed, and the islands were restored largely to their pre-exploitation state. Some of the endemic species of the NWHI include the Nihoa and Laysan finch, the Laysan duck (the "rarest native waterfowl in the United States"), and the Nihoa fan palm. Other notable species are the Laysan albatross, the highly endangered Hawaiian monk seal, and the green sea turtle. The only native trapdoor spiders in the Hawaiian archipelago ("Nihoa" spp.), recently discovered, are found only here.