Nene  (Branta sandvicensis)

As the human population on Hawaii expanded nene numbers began to fall, and recent evidence suggests that the population already numbered less than 300 individuals many centuries ago (7). Following excessive hunting and loss of habitat just 20 to 30 individuals remained in 1949 (6). Hunters targeted birds during the breeding season when they were particularly vulnerable. Today the main threat to this species comes from a lack of suitable habitat and from introduced animals such as mongooses, feral dogs and cats, which prey on eggs and young birds (4). Factors such as inbreeding depression and disease transmission may also pose difficulties for captive-reared birds (5).

The nene has been rescued from the brink of extinction by a long-running conservation programme (6). Breeding programmes in both Hawaii and at the Wildfowl and Wetlands Trust in Britain have been working to breed captive birds for release into the wild (10). By 1997, 2,450 birds had been released (2) and by 1999 the total population was estimated at 960 to 1,000 birds (5). Nene are protected within national parks on both Hawaii and Maui, and within these areas predators are controlled to a limited degree (5). Although reintroduced populations are still not completely self-sustaining, the nene nevertheless represents a major conservation success story.