Population numbers of the Juan Fernández firecrown are thought to be in the low hundreds (1), and theJuan Fernández Islands are among the 11 most seriously threatened, natural areas in the world as a result of hundreds of years of habitat degradation and the introduction of exotic species (4). Repeated burning, deforestation and the introduction of animals and plants, and consequently disease, have resulted in 75 percent of the endemic, vascular flora being on the verge of extinction (7). This, together with the introduction of rabbits and goats, has reduced vegetation cover and increased erosion, so that now more than 15 percent of the island is severely eroded and lacking vegetation (6). The introduced species that are of specific concern for the Juan Fernández firecrown include rats, dogs, pigs, semi-feral cattle, rabbits, which have severely affected the low elevation flora, including some hummingbird nectar plants; coatis and bramble. Coatis thrive throughout both lowland and upland areas and are opportunistic foragers, feeding on the birds and their eggs; while bramble shades out regenerating forest (6), and bears flowers too small for the Juan Fernández firecrown to feed on (2). Due to these changes in habitat, the green-backed firecrown (Sephanoides sephanoides), which can feed on bramble,is increasing in number and is competing with the Juan Fernández firecrown for space. The Juan Fernández firecrown is also less able to protect itself from predation than the green-backed firecrown. In addition to these threats is the steady impact of collection by scientists and private collectors (6).