Nēnē, the Hawaiian goose, is named for the soft honking it makes, a low two-note sound that carries across open ground. It is endemic to these islands, descended from a Canada goose ancestor that arrived about 500,000 years ago and stayed. Half a million years of isolation reshaped it: the toes carry reduced webbing, an adaptation to the rocky lava flows where the bird walks and nests, and unlike other waterfowl, it mates on land. It breeds from August to April, the longest breeding season of any goose, and the female incubates one to five eggs for about 30 days in the cover of low brush while the male keeps watch for mongoose. There were once perhaps 25,000 of them, and by the 1950s there were about 30. Captive breeding brought nēnē back to Hawai‘i Island, Maui, Kaua‘i, and Moloka‘i, though not to O‘ahu, where they had been absent since the 1700s. Then, in 2014, a pair turned up at James Campbell National Wildlife Refuge in Kahuku and nested there, and no one had released them. They had come on their own. Nēnē remain rare on this island, and a sighting is never promised. The refuge is closed through breeding and fledging season, and opens for free guided tours on Saturday mornings from October through the end of February.