WatchList Species Account for Nihoa Finch (Telespiza ultima) |
Qualifies for the list as a Red List Species
|Photo: Jack Jeffrey
The Nihoa Finch is endemic to Nihoa Island, a small, rocky island about 156 acres in total size, with a high point of 909 feet, part of the Hawaiian Islands National Wildlife Refuge. Nihoa has steep cliffs on three sides, making landing there difficult. There are several freshwater seeps on the island. Nihoa was inhabited by the Polynesians from 1000 to 1700 A.D., with a population of as many as 175 people, but since then the island has been uninhabited.
Like the Laysan Finch, the Nihoa Finch is a member of the Hawaiian Honeycreeper subfamily. Its preferred habitat is low shrubs and grasses, which cover most of the island. The species nests in cavities on cliffs and rock crevices, or in holes under piles of loose rock; it feeds on eggs, insects, seeds, flowers, and carrion.
Studies show marked fluctuations in Nihoa Finch populations, probably related to climatic events. Current estimates put the Nihoa Finch at 3,177 individuals, with a long-term slightly downward trend.
The accidental introduction of mammalian predators and/or alien plants and insects could bring about the rapid extinction of this species. Three species of alien plants already exist on Nihoa, which visiting scientists work to control by manual weeding. Other threats are weather events such as drought, storms and hurricanes.
Although no vertebrate predators are found on Nihoa, occasionally nonnative, nonmigratory passerines appear on the island, probably colonizing from Kauai. This could introduce avian diseases against which the Nihoa Finch, so long in isolation, has no resistance.
As insurance against extinction, an attempt was made by the U.S. Fish and Wildlife Service in 1967 to introduce the bird to French Frigate Shoals, but it had died out there by 1984; at present a plan to introduce a population onto Midway Island is under consideration.
Rats on Midway Island, which caused introduced Laysan Finches to become extirpated, have now been eradicated. Nihoa Island can be visited only by permit, generally given only to researchers. Efforts are made to insure that visiting scientists do not inadvertently introduce alien plants or animals. The bird is listed under the Endangered Species Act as endangered and BirdLife International has classified it as critical.