The Hawaiian Islands have a wide variety of plant, marine and animal life. Vegetation zones include: coastal, dryland forest, mixed open forest, rain forest, subalpine and alpine. More than 90 percent of the native plants and animals living in Hawaii are found nowhere else in the world, and a greater variety of fish exist in Hawaiian waters than elsewhere. The humuhumunukunukuapuaa is the unofficial state fish. Hawaii is sometimes called the Endangered Species Capital of the World. At least one third of all the endangered species in the United States are found in Hawaii including the Nene Goose (official state bird), the Humpback Whale (official state marine mammal), the Pacific Green Sea Turtle and the Pueo (Hawaiian owl). The exotic species, man, poses a greater threat than nature to Hawaii's native flora and fauna. CLIMATE    The Hawaiian Islands have only two seasons: "summer" between May and October and "winter" between October and April. The climate is subtropical, with a normal annual temperature of 77°F, making these islands "- the peacefullest, restfullest, balmiest, dreamiest haven of refuge for a worn and weary spirit the surface of the earth can offer.