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 63 ha in total size, with a high point of 277 m. It has steep cliffs on three sides, making landing 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 it has been uninhabited. It is part of the Hawaiian Islands National Wildlife Refuge. Like the Laysan Finch, the Nihoa Finch is a member of the Hawaiian Honeycreeper subfamily. It is extremely tame and curious and can be captured by hand. Its preferred habitat is low shrubs and grasses, which cover about 2/3 of the island. It nests in cavities in cliffs and rock crevices or in holes under piles of loose rock; it feeds on eggs of seabirds, insects, seeds, flowers, and carrion. Population demonstrates marked fluctuations, probably related to climatic events.

Current estimates put it at 3,177 individuals with a long-term slightly downward trend. In monitoring from 1967 to 1986, population ranged from a high of 6,686 in 1968 to 946 in 1986, with a median of 2,987. Some of the variation may be due to the fact that surveys were done at different times of year and using different protocols.

The accidental introduction of mammalian predators or of alien plants and insects could bring about the rapid extinction of the species. Three species of alien plants already exist there, which visiting scientists work to control by manual weeding. Other threats are weather events such as drought, storms and hurricanes. No vertebrate predators are found on Nihoa Island; occasionally nonnative, nonmigratory passerines have been seen on Hihoa, probably colonizing from Kauai. These could introduce avian diseases against which the Nihoa Finch, so long in isolation, has no resistance. As insurance against extinction of the bird on Nihoa through stochastic events, 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.