The ecology and conservation of the world's largest butterfly, endangered Ornithoptera alexandrae Rothschild (Lepidoptera: Papilionidae), known only from the Popondetta and Afore regions of Papua New Guinea's Northern Province, are outlined and discussed. The continuing loss of habitat to the oil palm and timber industries in the Popondetta area is detailed, and the neglect of protection of the species over the past decade is stressed. The results of a recent two month (April-June 1991) field survey to update knowledge of the present-day distributional status of the species are outlined. An action plan is given which is aimed at greatly improving the survival prospects of the species. Among other factors, it emphasizes the need to continue surveys to provide an in-depth update of the present status of the species, to set aside reserves of remaining natural habitat, to recreate new areas of habitat, to carry out further ecological research and education, and to work towards the economic utilisation of the species for its own benefit.
