Nihoa (also known as Bir Island or Moku Manu) is a small island in the Northwestern Hawaiian Islands located 120 miles (190 km) northwest of the island of Niihau and 280 miles (450 km) northwest of Honolulu. Nihoa is composed of 173.234 acres (701,050 m²) of dry land, surrounded by 140,554 acres (568.80 km²) of coral reef.