Sir

Your News story 'Feathers fly over Hawaiian bird' (Nature 456, 682–683; 2008) raises important questions about the population status of the endangered Hawaii akepa (Loxops coccineus) in the Hakalau Forest National Wildlife Refuge in Hawaii. It focuses on the research of Leonard Freed and his team on Hawaii's endemic birds, the implications of which have been seriously considered by the US Fish and Wildlife Service (USFWS).

USFWS staff, including refuge biologist Jack Jeffrey, took several actions to ensure that Freed's research did not fall victim to differences of opinion or personality. The Hawaii Forest Bird Recovery Team was asked to review Freed's work and its management implications on multiple occasions. Also, the USFWS initiated a review of the population status of the akepa by independent scientists and hosted a workshop in October 2008, in which Freed participated, to identify research and management priorities for the refuge.

The consensus of these reviews was that the akepa population is showing no signs of imminent collapse and faces greater threats than competition from the Japanese white-eye (Zosterops japonicus). The majority of the 21 scientists participating in the workshop disagreed with Freed's conclusions for several reasons.

First, they had a contrasting assessment of the population status of the akepa, based on annual abundance estimates taken over the past 21 years. These data did not suggest a population crash or a negative association with the Japanese white-eye.

Second, the scope of inference from annual surveys differed from that of Freed's work. Annual surveys were based on 300 stations established using a probability sample of the entire 13,400-hectare refuge, allowing inferences to be made for the whole refuge. Freed's conclusions were based on observations from a few small study sites within the refuge, undermining the extrapolation of his results to a refuge-wide phenomenon.

Given current budgetary challenges, management actions such as habitat restoration and the removal of hoofed animals that damage habitat are the top management priorities.